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四(二苯甲酰甲烷)合铕酸二乙铵的激发光谱和荧光光谱

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化学学报 1990年第1期48卷 58-63页

作者：金林培 Bunzli J.-c.G. Plancherel d. 北京师范大学化学系洛桑大学

在296和77K测定了四(二苯甲酰甲烷)合铕酸二乙铵[(c_2H_5)_2NH_2Eu(dBM)_4]的高分辨激发光谱和荧光光谱。光谱数据说明在77K,配合物含有五种Eu(Ⅲ)格位,详细分析发光光谱说明。由于配合物中配位体里的苯基错位产生不同的构型,形成了不同... 详细信息

在296和77K测定了四(二苯甲酰甲烷)合铕酸二乙铵[(c_2H_5)_2NH_2Eu(dBM)_4]的高分辨激发光谱和荧光光谱。光谱数据说明在77K,配合物含有五种Eu(Ⅲ)格位,详细分析发光光谱说明。由于配合物中配位体里的苯基错位产生不同的构型,形成了不同的Eu(Ⅲ)物种,显示出不同的晶体场效应,Eu(Ⅲ)离子的这种灵敏性可以作为晶体构型探针。

关键词：铕配合物激发光谱荧光光谱

A MOdEL FOR BAINITIc TRANSFORMATION KINETIcS WITH PARABOLIc NUcLEATION RATE

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Acta Metallurgica Sinica(English Letters) 2001年第1期14卷 63-71页

作者： c.c. Liu, K.F. Yao and Z Liu (department of Mechanical Engineering, Tsinghua University, Beijing 100084, china) dept. of Mech. Eng. Tsinghua Univ. Beijing 100084 China

Based on the assumptions of parabolic variation of nucleation rate versus time and transformation kinetics depending mainly on nucleation rate, a different model for bainitic transformation kinetics in hypoeutectoid steels was established. And this model was proved to be effective in the description of bainitic transformation by comparison with the result of conventional Avrami equation.

关键词： bainitic transformation kinetics parabolic nucleation rate rapid growth

Impacts of Urbanization on the Precipitation characteristics in Guangdong Province, china

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Advances in Atmospheric Sciences 2020年第7期37卷 696-706页

作者： Meng YAN Johnny c.LcHAN Kun ZHAO School of Atmospheric Sciences Nanjing UniversityNanjing 210023China School of Energy and Environment City University of Hong KongHong KongChina State Key Laboratory of Severe Weather and Joint center for Atmospheric Radar Research CMA/NJUBeijing 100081China

With the development of urbanization,whether precipitation characteristics in Guangdong Province,china,from 1981 to 2015 have changed are investigated using rain gauge data from 76 *** characteristics include annual precipitation,rainfall frequency,intense rainfall(defined as hourly precipitation≥20 mm),light precipitation(defined as hourly precipitation≤2.5 mm),and extreme rainfall(defined as hourly rainfall exceeding the 99.9 th percentile of the hourly rainfall distribution).during these 35 years,the annual precipitation shows an increasing trend in the urban *** rainfall frequency and light precipitation have a decreasing trend,intense rainfall frequency shows an increasing *** heavy and extreme rainfall frequency both exhibit an increasing trend in the Pearl River delta region,where urbanization is the most *** trends in both the warm seasons(May-October)and during the pre-flood season(April-June)appear to be more *** the contrary,the annual precipitation amount in rural areas has a decreasing *** the heavy and extreme precipitation also show an increasing trend,it is not as strong and significant as that in the urban *** periods in which a tropical cyclone makes landfall along the South china coast,the rainfall in urban areas has been consistently more than that in surrounding *** precipitation in the urban areas and to their west is higher after 1995,when the urbanization *** results suggest that urbanization has a significant impact on the precipitation characteristics of Guangdong Province.

关键词： rainfall flood extreme

Effects of variable viscosity and temperature modulation on linear Rayleigh-Bénard convection in Newtonian dielectric liquid

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Applied Mathematics and Mechanics(English Edition) 2019年第11期40卷 1601-1614页

作者： P.G.SIddHESHWAR d.UMA S.BHAVYA department of Mathematics Bangalore UniversityBengaluru 560056India department of computer Science and Engineering PES UniversityBengaluru 560085India department of Mathematics Atria Institute of TechnologyBengaluru 560024India

The linear Rayleigh-Bénard electro-convective stability of the Newtonian dielectric liquid is determined theoretically subject to the temperature modulation with time.A perturbation method is used to compute the critical Rayleigh number and the wave *** critical Rayleigh number is calculated as a function of the frequency of modulation,the temperature-dependent variable viscosity,the electric field dependent variable viscosity,the Prandtl number,and the electric Rayleigh *** effects of all three cases of modulations are established to delay or advance the onset of the convection *** addition,how the effect of variable viscosity controls the onset of convection is studied.

关键词： dielectric liquid temperature dependent variable viscosity electric field dependent variable viscosity electric Rayleigh number temperature modulation

design and Robustness Analysis of a Wave-Based controller for Tethered Towing of defunct Satellites

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IEEE/cAA Journal of Automatica Sinica 2023年第1期10卷 278-280页

作者： Rui Qi Yang Zhang Krishna d.Kumar the School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China IEEE the department of Aerospace Engineering Ryerson UniversityToronto M5B 2K3Canada

dear Editor, A microgravity environment in space, the elasticity of the tether,and complex flexible appendages make the tethered-towing system a nonlinear and underactuated system, which is sensitive and difficult to stabilize. This letter develops a controller based on wave propagation for tethered towing of defunct satellites, and carries out a robustness analysis of the controller via numerical simulation.

关键词： system elasticity letter

Experimental validation of a new morphing trailing edge system using Price-Pa?doussis wind tunnel tests

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chinese Journal of Aeronautics 2019年第6期32卷 1353-1366页

作者： d.cOMMUNIER R.M.BOTEZ T.Wong Laboratory of Applied Research in Active controls Avionics and AeroServoElasticity (LARCASE)ETS

This paper presents the design and manufacturing of a new morphing wing system carried out at the Laboratory of Applied Research in Active controls, Avionics and AeroServoElasticity(LARcASE) at the ETS in Montréal. This first version of a morphing wing allows the deformation of its trailing edge, denote by Morphing Trailing Edge(MTE). In order to characterize the technical impact of this deformation, we compare its performance with that of a rigid aileron by testing in the LARcASE’s price-Pa?doussis subsonic wind tunnel. The first set of results shows that it is possible to replace an aileron by a MTE on a wing, as an improvement was observed for the MTE aerodynamic performances with respect to the aileron aerodynamic *** improvement consisted in the fact that the drag coefficient was smaller, and the lift-to-drag ratio was higher for the same lift coefficient.

关键词： Aerodynamic performances Aileron Morphing wing Trailing edge Wing tunnel tests

MoS2 as a long-life host material for potassium ion intercalation

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Nano Research 2017年第4期10卷 1313-1321页

作者： Xiaodi Ren Qiang Zhao William d. Mcculloch Yiying Wu department of chemistry and Biochemistry The Ohio State University 151 W Woodruff Ave Columbus OH 43210 USA college of chemical Engineering Sichuan University Chengdu 610065 China

Electrochemical potassium ion intercalation into two-dimensional layered MoS2 was studied for the first time for potential applications in the anode in potassium-based batteries. X-ray diffraction analysis indicated that an intercalated potassium compound, hexagonal K0.4MoS2, formed during the intercalation process. despite the size of K^＋, MoS2 was a long-life host for repetitive potassium ion intercalation and de-intercalation with a capacity retention of 97.5% after 200 cycles. The diffusion coefficient of the K^＋ ions in KxMoS2 was calculated based on the Randles-Sevcik equation. A higher K^＋ intercalation ratio not only encountered a much slower K^＋ diffusion rate in MoS2, but also induced MoS2 reduction. This study shows that metal dichalcogenides are promising potassium anode materials for emerging K-ion, K-O2, and K-S batteries.

关键词： potassium ion intercalation potassium battery MoS2 phase evolution potassium ion diffusion

Early Results of Urothelial carcinoma Screening in a Risk Population of coke Workers:Urothelial carcinoma among coke Workers

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Biomedical and Environmental Sciences 2010年第4期23卷 300-304页

作者： GIBERTI c GALLO F ScHENONE M GENOVA A department of Surgery Division of Urology San Paolo Hospital Savona Italy Service of Industrial Medicine Italiana Coke Industry S.r.l

Objective To present the protocol and the early results of a urothelial carcinoma （Uc） screening analysis performed in a risk population of coke workers. Methods Between June 2006 and October 2008, 171 male workers （mean age 43 years）, employed in a Ligurian coke plant （Italiana coke S.r.l） and exposed to polycyclic aromatic hydrocarbons （PAHs） for a median period of 16 years, underwent screening for Uc. Urological evaluation included medical history, physical examination, routine laboratory tests, urine analysis, urinary cytology and ucyt＋ assay. In the event of signs and symptoms suggestive of Uc or positive urinary tests, the workers were also subjected to urinary ultrasonography and cystoscopy with biopsy of any suspicious lesions. Results Regarding the laboratory tests, 19/171 （11%） ucyt＋ samples were considered inadequate and were excluded from the outcomes assessment. Overall, urine analysis, cytology and ucyt＋ were positive in 18/152 （12%） subjects who showed no evidence of Uc at the scheduled check-ups. No significant association was identified between marker positivity and occupational activity. conclusions Our results fail to show an increased risk of Uc among the coke workers evaluated. However, they will need to be confirmed in the future by a larger enrollment and a longer follow-up in order to assess the definitive risk for Uc after exposure to coke.

关键词： Bladder cancer Screening Occupation Risk factor Urinary markers

Influence of metal support in-plane symmetry on the corrugation of hexagonal boron nitride and graphene monolayers

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Nano Research 2018年第9期11卷 4643-4653页

作者： Antonio d. Martinez-Galera Jose M. Gomez-Rodriguez departamento de Fisica de la Matefia condensada Universidad Autonoma de Madrid Madrid E-28049 Spain condensed Matter Physics center (IFIMAc) UniversidadAutdnoma de Madrid Madrid E-28049 Spain Instituto Nicolds cabrera Universidad Autonoma de Madrid Madrid E-28049 Spain

Predicting the properties of two-dimensional （2d） materials as graphene and hexagonal boron nitride （h-BN） monolayers after their growth on any given substrate is a major challenge. While the influence of the electron configuration of the atoms of the underlying surface is well-understood, the effect of substrate geometry still remains unclear. The structural properties of h-BN monolayers grown on a rectangularly packed Rh（110） surface were characterized in situ by ultrahigh vacuum scanning tunneling microscopy and were compared to those that this material exhibits when grown on substrates showing different crystallographic orientations. Although the h-BN monolayer grown on Rh（110） was dominated by a unique quasiunidimensional moir6 pattern, suggesting considerable interface interaction, the moir6 corrugation was unexpectedly smaller than those reported for strongly interacting interfaces with hexagonal-terminated substrates, owing to differences in the possible binding landscapes at interfaces with differently oriented substrates. Moreover, a rule was derived for predicting how interface corrugation and the existence and extent of subregions within moir6 supercells containing favorable sites for orbital mixing between h-BN monolayers and their supports depend on substrate symmetry. These general symmetry considerations can be applied to numerous 2d materials, including graphene, thereby enabling the prediction of how substrate choice determines the properties of these materials. Furthermore, they could also provide new routes for tuning 2d material properties and for developing nanotemplates showing different geometries for Krowing adsorbate superlattices.

关键词： hexagonal boron nitride graphene two-dimensional materials scanning tunneling microscopy moire superstructures nanotemplates