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Hβ负载锆催化剂的研制及其催化性能和结构性能的研究

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燃料化学学报 2002年第4期30卷 358-362页

作者：李隽春张慧 d.g. Evans 段雪北京化工大学可控化学反应科学与技术基础教育部重点实验室北京100029

根据层状四水硫酸锆和Hβ沸石各自的催化性能和结构特点 ,设计并制备得到Hβ负载锆 (Zr Hβ)催化剂。以异丙苯歧化反应为目标体系 ,研究了Zr Hβ的催化性能。利用吡啶吸附程序升温脱附和低温氮吸附等方法研究了Zr Hβ和Hβ的表面酸性和... 详细信息

根据层状四水硫酸锆和Hβ沸石各自的催化性能和结构特点 ,设计并制备得到Hβ负载锆 (Zr Hβ)催化剂。以异丙苯歧化反应为目标体系 ,研究了Zr Hβ的催化性能。利用吡啶吸附程序升温脱附和低温氮吸附等方法研究了Zr Hβ和Hβ的表面酸性和孔结构 ,与反应性能进行关联。结果表明 ,Zr Hβ较Hβ弱酸强度更弱、强酸强度更强 ,导致其歧化反应活性较Hβ大大提高 ,歧化选择性较Hβ略有提高 ,但其初始歧化选择性较Hβ降低 ;Zr Hβ和Hβ的最可几孔径基本一致 ,因而Zr Hβ催化异丙苯歧化反应产物中间位对位

关键词：催化性能结构性能 Hβ负载锆催化剂异丙苯歧化吡啶吸附程序升温脱附酸性孔结构

A novel benzo[4,5]furo[3,2-d]pyrimidine-based host as a n-type host for blue phosphorescent organic light-emitting diodes

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Science China Materials 2022年第4期65卷 1028-1033页

作者： Junsu Ha Junseop Lim Jun Yeob lee School of Chemical Engineering Sungkyunkwan University2066Seobu-roJangan-guSuwon-siGyeonggi-do16419Republic of Korea

An electron-transport-type host was synthesized using a benzo[4,5]furo[3,2-d]pyrimidine(BFP)core to develop a high triplet energy *** host was designed to have both the tetraphenylsilyl blocking group and the hole-transport-type carbazole *** the device application,the host was used as an electron-transport-type host mixed with a hole-transport-type 3,3'-di(9H-carbazol-9-yl)-1,1†-biphenyl(mCBP)host in the blue phosphorescent organic light-emitting diodes(PhO-LEds)doped with a[[5-(1,1-dimethylethyl)-3-phenyl-1H-imidazo[4,5-b]pyrazin-1-yl-2(3H)-ylidene]-1,2-phenylene]bis-[[6-(1,1-dimethylethyl)-3-phenyl-1H-imidazo[4,5-b]pyrazin-1-yl-2(3H)-ylidene]-1,2-phenylene]iridium(Ir(cb)3)blue *** a result,the mCBP:CzBFPmSi mixed host showed high external quantum efficiency over 20%at 1000 cd m^(−2) and low efficiency roll-off in the blue PhOLEds.

关键词： blue device host efficiency lifetime

Numerical modelling of a low power non-transferred arc plasma reactor for methane conversion

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Plasma Science and Technology 2019年第6期21卷 29-37页

作者： B I MIN d K dINH d H lee T H KIM S CHOI Institute for Nuclear Science and Technology Jeju National University 102 Jejudaehak-ro Jeju 63243Republic of Korea University of Science and Technology(UST) 217 Gajeong-ro Yuseong-gu Daejeon 34113 Republic of Korea Korea Institute of Machinery and Materials 156 Gajeongbuk-ro Yuseong-gu Daejeon 34103 Republic of Korea department of Nuclear and Energy Engineering Jeju National University 102 Jejudaehak-ro Jeju 63243Republic of Korea

Thermal flow characteristics and the methane conversion reaction in a low power arc plasma reactor for efficient storage and transport of methane,which is the main component of shale gas,were *** temperature and velocity distributions were calculated according to the type of discharge gases and arc current level by a self-developed magnetohydrodynamics (MHd)code and a commercial ANSYS-FLUENT code;the transport of chemical species was analyzed as including the chemical reactions of methane *** simulated results were verified by the comparison of calculated and measured arc voltages with permissible low error as under 4%.Three C2 hydrocarbon gases with ethane (C2H6),ethylene (C2H4),and acetylene (C2H2)were selected as the converted species of methane from experimental *** mass fraction of C2 hydrocarbons and hydrogen as the product of the conversion reaction at the reactor was also *** values show good agreement with the actual experimental results in that the major conversion reaction occurred in C2H2 and hydrogen,and the conversions to C2H6,C2H4,and hydrogen were minor reactions of methane pyrolysis conversion.

关键词： numerical modelling non-transferred arc plasma methane chemical reaction

Optimization of Mass Bleed Control for Base drag Reduction of Supersonic Flight Bodies

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Journal of Thermal Science 2006年第3期15卷 206-212页

作者： Y.-K.lee H.-d.Kim School of Mechanical Engineering Andong National University388 Songcheon-dongAndong760-749Korea

The minimization of base drag using mass bleed control is examined in consideration of various base to orifice exit area ratios for a body of revolution in the Mach 2.47 freestream Axisymmetric, compressible, rmss-averaged Navier-Stokes equations are solved using the standard k-ω model, a fully implicit finite volume scheme, and a second order upwind scheme. Base flow charcteristics are explained mgaarding the base configuration as well as the injection parameter which is defined as the mass flow rate of bleed jet non-dimensionalized by the product of the base area and fieestream mass flux. The results obtained through the present study show that for a smaller base area, the optimum mass bleed condition leading to minimum base drag occurs at relatively larger mass bleed, and a lalger orifice exit can offer better drag control.

关键词： base drag mass bleed drag reduction separation supersonic flow

Latest lattice results for baryon spectroscopy

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Chinese Physics C 2010年第9期34卷 1281-1285页

作者： d.g.Richards Jefferson Laboratory 12000 Jefferson Avenue Suite #1Newport NewsVA 23606USA

Theoretical and computational advances have enabled not only the masses of the ground states,but also some of the low-lying excited states to be calculated using Lattice gauge *** this talk,I look at recent progress aimed at understanding the spectrum of baryon excited states,including both baryons composed of the light u and d quarks,and of the heavier quarks.I then describe recent work aimed at understanding the radiative transitions between baryons,and in particular the N-Roper transition.I conclude with the prospects for future calculations.

关键词： Lattice QCd spectroscopy hadronic physics.

Landslide inventory validation and susceptibility mapping in the gerecse Hills, Hungary

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geo-Spatial Information Science 2021年第3期24卷 498-508页

作者： dávid.g.rzsenyi gáspár Albert department of Cartography and.g.oinformatics Eötvös Loránd UniversityBudapestHungary

Landslides pose a threat to property both in the populated and cultivated areas of the gerecse Hills (Hungary). The currently available landslide inventory database holds the records from many sites in the area, but the database is out-of-date. Here we address the problem of revising the National Landslides Cadastre landslide inventory database by creating a landslide suscept-ibility map with a multivariate model based on likelihood ratio functions. The model is applied to the TandEM-X dEM (0.4″ res.), the current landslide inventory of the area, and data acquired from geological maps. By comparing the distributions of four variables in the landslide and non-landslide area with grid computation methods, the model yields landslide susceptibility estimates for the study area. The estimations show to what extent a certain area is similar to the sample areas, therefore, its likelihood to be affected by landslides in the future. The accuracy of the model predictions was checked in the field and compared to the results of our previous study using the SRTM-1 dEM for a similar analysis. The model gave accurate estimates when certain correction measures were applied to the input datasets. The limitations of the model, the input datasets, and the suggested correction measures are also discussed.

关键词： Landslide susceptibility landslide inventory TandEM-X gerecse Hills landslides geomorphometry

Rare tau decays from BABAR

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Chinese Physics C 2010年第6期34卷 907-911页

作者： g.d.Lafferty School of Physics and Astronomy The University of Manchester

The BABAR experiment has now completed data taking and with an integrated luminosity of 531 fb^-1 of e^＋e^- collision data has recorded some 480 million tau-pair events. Various studies of suppressed, rare and forbidden decays of the tau have been conducted, including searches for high-multiplicity decays, for second-class hadronic weak currents, and for lepton-flavour violation.

关键词： particle physics tau leptons rare decays

Microstructure and Mechanical Properties of Nanocrystalline Tungsten Thin Films

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Journal of Materials Science & Technology 2010年第1期26卷 87-92页

作者： H.L. Sun, Z.X. Song, d.g. guo, F. Ma and K.W. Xu State Key Laboratory for Mechanical Behavior of Materials, School of Materials Science and Engineering, Xi an Jiaotong University, Xi’an 710049, China State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and Engineering Xi'an Jiaotong University Xi'an 710049 China

Tungsten （W） thin films were prepared by magnetron sputtering onto Si （100） substrates. Their microstructures were characterized by X-ray diffraction （XRd）, field emission scanning electron microscopy （FE-SEM） and transmission electron microscopy （TEM）. The hardness and modulus were evaluated by nanoindentation. It is found that a 30 nm Cr sticking layer induces structure changes of deposited W film from β-W to α-W structure. In addition, remarkable hardness enhancement both for the deposited and annealed W films, were compared with that of bulk coarse-grained W, although their nanoindentation modulus is very close to that of corresponding bulk W. The intrinsic reasons that lead to structure changes and super hardness are discussed.

关键词： Tungsten film Microstructure Nanoindentation Hardness Modulus

generalized megaviscera of lupus:Refractory intestinal pseudo-obstruction,ureterohydronephrosis and megacholedochus

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World Journal of gastroenterology 2009年第28期15卷 3555-3559页

作者： Frederick d Park Jeffrey K lee ganga d Madduri Pradipta ghosh department of Medicine University of California San Diego San Diego California 92103 United States division of gastroenterology and Hepatology University of California San Diego San Diego California92103 United States

dilated dysfunction involving multiple visceral organs has been reported in patients with systemic lupus erythematosus （SLE）. Chronic intestinal pseudoobstruction （CIPO） resulting from intestinal smooth muscle damage has presented in conjunction with ureterohydronephrosis and, more rarely, biliary dilatation （megacholedochus）. While the molecular pathogenesis is largely unknown, observed histopathologic features include widespread myositis, myocyte necrosis in the intestinal muscularis propria with subsequent atrophy and fibrosis, preserved myenteric innervations and little vasculitis. High dose immunosuppression usually results in resolution of symptoms with recovery of smooth muscle function, indicative of an autoimmune etiology. We report a patient with SLE who presented with intestinal pseudo-obstruction, ureterohydronephrosis and megacholedochus, and present images that illustrate megaviscera simultaneously involving all 3 visceral organs. Since the co-manifestation of all 3 is unusual and has been reported only once previously, we have termed this rare clinical syndrome generalized megaviscera of lupus （gML）. Although the SLE disease-activity parameters responded to aggressive immunomodulative therapy in our patient, clinical evidence of peristaltic dysfunction persisted in all involved viscera. This is a variation from the favorable outcomes reported previously in SLE patients with gML and we attribute this poor clinical outcome to disease severity and, most importantly, delayed clinical presentation. Since inflammation followed by atrophy and fibrosis are key aspects in the pathogenesis and natural history of gML, the poor response in our patient who presented late in the clinical course may be the result of ＇burnt out＇ inflammation with irreversible end-stage fibrosis. Thus, early recognition and timely initiation of treatment may be the key to recover visceral peristaltic function in patients with gML.

关键词： Systemic lupus erythematosus Intestinalpseudo-obstruction Biliary tract diseases Hydroureter Hydronephrosis Smooth muscle Autoimmune myositis