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载体对其负载的Cu-Co双金属催化剂上5-羟甲基糠醛氢解选择性生成2,5-二甲基呋喃的影响（英文）

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Chinese Journal of Catalysis 2017年第4期38卷 699-709页

作者： Sanjay Srivastava g.C.Jadeja Jigisha Parikh 萨达尔瓦拉巴伊国立技术研究所化工系

碳-氧键氢解是生物质呋喃基化合物制备交通燃料常见的模型反应,其中5-羟甲基糠醛(HMF)转化为汽油添加剂2,5-二甲基呋喃(DMF)尤为引人关注.本文采用CeO_2,ZrO_2和Al_2O_3负载的Cu-Co双金属催化剂用于HMF选择性氢解制DMF的反应中.采用X射... 详细信息

碳-氧键氢解是生物质呋喃基化合物制备交通燃料常见的模型反应,其中5-羟甲基糠醛(HMF)转化为汽油添加剂2,5-二甲基呋喃(DMF)尤为引人关注.本文采用CeO_2,ZrO_2和Al_2O_3负载的Cu-Co双金属催化剂用于HMF选择性氢解制DMF的反应中.采用X射线衍射、N_2吸附-脱附、投射电镜、H_2-程序升温还原、氨-程序升温脱附和元素分析表征了新鲜的和使用过催化剂的结构,并将其与催化活性相关联.Cu-Co/CeO_2催化剂通过在大的Cu颗粒上还原C=O键生成了最多的2,5双(羟甲基呋喃)(BHMF).但Cu-Co/Al_2O_3催化剂具有高度分散的Cu,Cu-Co复合氧化物和大量的弱酸位,因而生成DMF的选择性最高.Cu-Co/ZrO_2催化剂则由于存在强酸位,DMF选择性较低,生成了各种过度氢解产物,如2,5而甲基四氢呋喃和5,5-二(亚甲基)双(2-甲基呋喃).因此,考察了Cu-Co/Al_2O_3催化剂上的反应路径,以及温度、氢气压力和时间等操作条件的影响,使其具有较优的HMF转化率和DMF选择性.

关键词： 5-羟甲基糠醛加氢氢解铜-钴双金属生物燃料

Testing of Lightning Protective System of a Residential Structure： Comparison of Data Obtained in Rocket-triggered Lightning and Current Surge generator Experiments

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高电压技术 2008年第12期34卷 2575-2582页

作者： g. Maslowski V.A. Rakov S. Wyderka J. Bajorek B.A. DeCarlo J. Jerauld g.H. Schnetzer J. Schoene M.A. Uman K.J. Rambo D.M. Jordan W. Krata Rzeszow University of Technology Rzeszow 35-959 Poland University of Florida Gainesville 32611 USA

We present a comparison of data obtained during testing of lightning protective system of a residential structure in rocket-triggered lightning experiment at the International Center for Lightning Research and Testing(ICLRT)at Camp Blanding,Florida,and current surge generator experiment at Rzeszow University of Technology in *** different configurations of LPS were tested in Poland with the dc grounding resistances of the entire system 4.09 Ω(LPS 1a),1.65 Ω(LPS 1b),and 2.88 Ω(LPS 2).For LPS 1a with three ground rods the value of the peak current entering the electrical circuit neutral was about 56% of the injected current peak,and for LPS 1b with two additional ground rods and two 5 m long buried horizontal conductors it was about 16%.For LPS 2 with five ground rods interconnected by a buried loop conductor this ratio was 21%.The current waveshapes in the ground rods differed from the injected current waveshapes and the current waveshapes in other parts of the test system,especially,for poorer-grounding LPS *** surge-generator results are consistent with those of triggered-lightning experiments at Camp Blanding,Florida(DeCarlo et al.,2008 [2]).

关键词：居民区雷电保护系统试验电流冲击发生器

VCSEL polarization modulation for pulse-per-second clock signal transfer in optical frequency distribution systems

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Optoelectronics Letters 2018年第5期14卷 376-379页

作者： g.M.Isoe A.W.R.Leitch and T.B.gibbon Centre for Broadband Communication Nelson Mandela UniversityPort Elizabeth 6031South Africa

In this paper, a novel vertical cavity surface emitting laser(VCSEL) polarization modulation technique based on polarization switching due to thermal heating in a single transverse mode class 10 g VCSEL at 1 310 nm is demonstrated experimentally. The inherent orthogonal polarization switching of the VCSEL carrier with changing bias is exploited in the transmission of pulse-per-second(PPS) timing clock signal. Experimental results show that PPS pulse widths of 9.97 μs and 9.98 μs are measured for back-to-back analysis and over 3.21 km of g 652 urban fibre transmission, respectively. This work provides a novel alternative for adoption in optical frequency and time transfer applications.

关键词： VCSEL 极化调整光频率分发系统信号热切换试验性 PPS

Collective migrations in an epithelial-cancerous cell monolayer

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Acta Mechanica Sinica 2021年第5期37卷 773-784,I0001页

作者： Jian‑Qing Lv Peng‑Cheng Chen Liu‑Yuan guan Wojciech T.góźdź Xi‑Qiao Feng Bo Li Institute of Biomechanics and Medical Engineering Applied Mechanics LaboratoryDepartment of Engineering MechanicsTsinghua UniversityBeijing 100084China Institute of Physical Chemistry Polish Academy of SciencesKasprzaka 44/5201‑224 WarsawPoland

Collective cell migration is extensively observed in embryo development and cancer *** these processes,the interactions between cells with distinct identities and fates are of importance for boundary formation and host defense against *** this paper,we explore the collective dynamics of a two-dimensional cell mixing monolayer consisting of non-tumorigenic mammary epithelial cells and breast cancer *** show that the epithelial-cancerous cell mixing system displays unique sorting *** epithelial cells aggregate to form scattered clusters,which perform random motion with simultaneous translation and rotation,strikingly distinct from the classical persistent random walk of individual migratory *** motility of cancer cells is markedly promoted by the epithelial clusters,exhibiting remarkable contact enhancement of locomotion.A discrete model based on the Johnson-Kendall-Roberts contact mechanics is proposed to identify the influence of intercellular interactions,active migration forces and cell-substrate friction forces on the collective cell *** findings could advance our understanding of many biological processes,such as cancer metastasis and tissue morphogenesis.

关键词： Collective cells Cell mixing Dynamics Cell-cell interaction

Modelling the interaction of the Astro Bio Cube Sat with the Van Allen's Belt radiative field using Monte Carlo transport codes

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Radiation Detection Technology and Methods 2022年第2期6卷 262-279页

作者： N.Burgio L.Cretara M.Corcione M.Frullini L.lannascoli A.Nascetti A.Santagata g.Palmerini A.Quintino J.R.Brucato A.Meneghin D.Paglialunga ENEA FSN-FISS-RNRC.R.CasacciaRomeItaly DIAEE Sapienza UniversitàDi RomaVia Eudossiana 1800184 RomeItaly School of Aerospace Engineering Sapienza University of RomeVia Salaria 85100138 RomeItaly INAF-Astrophysical Observatory of Arcetri L.go E.Fermi 550125 FlorenceItaly

Purpose The AstroBio Cube Satellite(ABCS)will deploy within the inner Van Allen belt on the Vega C Maiden Flight launch opportunity of the European Space *** this altitude,ABCS will experience radiation doses orders of magnitude greater than in low earth orbit,where CubeSats usually *** paper aims to estimate the irradiation effect on the ABCS payload in the orbital condition,their possible mitigation designing shielding solutions and performs a preliminary representativity simulation study on the ABCS irradiation with fission neutron at the TAPIRO(TAratura Pila Rapida Potenza 0)nuclear research reactor facility at *** We quantify the contributions of geomagnetically trapped particles(electron and proton),galactic Cosmic Rays(gCR ions),Solar energetic particle within the ABCS orbit using the ESA's SPace ENVironment information ***(Fluktuierende Kaskade-Fluctuating Cascade)code models the ABCS interaction with the orbital *** We found a shielding solution of the weight of 300 g constituted by subsequent layers of tungsten,resins,and aluminium that decreases on average the 20%overall dose rate relative to the shielding offered by the only satellite's ***,simulations of neutron irradiation of the whole ABCS structure within the TAPIRO's thermal column cavity show that a relatively short irradiation time is requested to reach the same level of 1 MeV neutron Silicon equivalent damage of the orbital *** The finding deserves the planning of a future experimental approach to confirm the TAPIRO's performance and establish an irradiation protocol for testing aerospatial electronic components.

关键词： galactic cosmic rays and solar energetic particles Spacecraft shielding Dosimetry Monte Carlo methods MCNP and FLUKA

Synthesis and electrocatalytic applications of flower-like motifs and associated composites of nitrogen-enriched tungsten nitride(W2N3)

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Nano Research 2020年第5期13卷 1434-1443页

作者： Sha Tan Brian M.Tackett Qun He Ji Hoon Lee Jingguang g.Chen Stanislaus S.Wong Department of Chemistry State University of New York at Stony BrookStony BrookNY 11794-3400USA Department of Chemical Engineering Columbia UniversityNew YorkNY 10027USA Chemistry Department Building 555Brookhaven National LaboratoryUptonNY 11973USA

We have sought to improve the electrocatalytic performance of tungsten nitride through synthetic control over chemical composition and *** particular,we have generated a thermodynamically unstable but catalytically promising nitrogen-rich phase of tungsten via a hydrothermal generation of a tungsten oxide intermediate and subsequent annealing in *** net product consisted of three-dimensional(3D)micron-scale flower-like motifs of W2N3;this architecture not only evinced high structural stability but also incorporated the favorable properties of constituent two-dimensional *** a performance perspective,as-prepared 3D W2N3 demonstrated promising hydrogen evolution reaction(HER)activities,especially in an acidic environment with a measured overpotential value of−101 mV at a current density of 10 mA/cm^*** further enhance the electrocatalytic activity,small amounts of precious metal nanoparticles(such as Pt and Au),consisting of variable sizes,were uniformly deposited onto the underlying 3D W2N3 motifs using a facile direct deposition method;these composites were applied towards the CO2 reduction reaction(CO2RR).A highlight of this series of experiments was that Au/W2N3 composites were found to be a much more active HER(as opposed to either a CO2RR or a methanol oxidation reaction(MOR))catalyst.

关键词： tungsten nitride synthesis composite morphology control electrocatalysis

ON　CERTAIN　BOUNDARY　VALUE　PROBLEMS　FOR　NONLINEAR　INTEgRODIFFERENTIAL　EQUATIONS

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Acta Mathematica Scientia 1994年第2期14卷 226-234页

作者： D. g. Pachpatte(Department of Mathematics and Statisics Marathwada University Aurangabad 431004 (Maharashtra), INDIA) Department of Mathematics and Statistics Marathwada University Aurangabad 431004 (Maharashtra) INDIA

In this paper we seek sufficient conditions for the existence, uniqueness and continuous dependene on parameter of solutions of certain boundary value problems for nonlinear integrodifferential equations. The main tool employed in our analysis is based on converting the problems into equivalent Volterra integral equations by means of green's function representation and the application of the Banach fixed point theorem.

关键词：边值问题非线性积分微分方程存在性唯一性

The light from the dark side of the moon

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The light from the dark side of the moon

Small-signal model parameter extraction of E-mode N-polar gaN MOS-HEMT using optimization algorithms and its comparison

作者： Norman g. gautreau.

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Journal of Semiconductors 2018年第7期39卷 59-66页

作者： d.k.panda g.amarnath t.r.lenka microelectronics and vlsi design group department of electronics and communication engineeringnational institute of technology silcharAssam788010India

An improved small-signal parameter extraction technique for short channel enhancement-mode N-polar gaN MOS-HEMT is proposed, which is a combination of a conventional analytical method and optimization techniques. The extrinsic parameters such as parasitic capacitance, inductance and resistance are extracted under the pinch-off condition. The intrinsic parameters of the small-signal equivalent circuit（SSEC） have been extracted including gate forward and backward conductance. Different optimization algorithms such as PSO, Quasi Newton and Firefly optimization algorithm is applied to the extracted parameters to minimize the error between modeled and measured S-parameters. The different optimized SSEC models have been validated by comparing the S-parameters and unity current-gain with TCAD simulations and available experimental data from the literature. It is observed that the Firefly algorithm based optimization approach accurately extracts the small-signal model parameters as compared to other optimization algorithm techniques with a minimum error percentage of 1.3%.

关键词： Firefly gaN MOS-HEMT PSO SSEC TCAD