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propulsion and power Research 2023年第2期12卷 180-198页

作者： p.Novotný p.Kudlácek j.Vacula Brno University of Technology BrnoTechnicka 2896/261669Czech Republic

Gas flow in the seal system can be expected during the operation of a turbocharger and is associated with negative effects on the quality of the lubricant or turbocharger *** flow also affects particulate matter production due to lubricant entrainment in the compressor or *** prediction of gas flow rates depends on many design parameters and the operating conditions of the turbocharger,but sufficiently accurate descriptions of the gas flow mechanisms and their quantification depending on the operating conditions have not yet been *** proposed computational approach simultaneously solves the gas dynamics in the seal system,the heat transfer in the turbocharger rotor-bearing system and the dynamics of the seal rings and rotor,including the *** computational model for the turbocharger of a heavy-duty vehicle engine is experimentally *** mechanisms have major influences on gas mass flow:the gas flow through the thin gap between the moving ring and groove and the flow through the ring *** results show that the importance of these mechanisms depends on several geometrical dimensions of the seal system and the operating conditions of the turbocharger,with a strong connection to the rotor dynamics and thermal load of the *** involving rotor movement or rotor thermal conditions are crucial,and their non-inclusion limits the ability to correctly predict gas mass flow.

关键词： Gas blow-by Gas flow Heat transfer Rotor dynamics Turbocharger Seal system

Effect of junction temperature on the large-signal properties of a 94 GHz silicon based double-drift region impact avalanche transit time device

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journal of Semiconductors 2013年第2期34卷 19-30页

作者： Aritra Acharyya Suranjana Banerjee j.p.Banerjee Institute of Radio physics and Electronics University of Calcutta92APC RoadKolkata-700009India Academy of Technology West Bengal University of TechnologyAdisaptagramHooghly-712121West BengalIndia

The authors have developed a large-signal simulation technique extending an in-house small-signal simulation code for analyzing a 94 GHz double-drift region impact avalanche transit time device based on silicon with a non-sinusoidal voltage excitation and studied the effect of junction temperature between 300 and 550 K on the large-signal characteristics of the device for both continuous wave （CW） and pulsed modes of operation. Results show that the large-signal RF power output of the device in both CW and pulsed modes increases with the increase of voltage modulation factor up to 60%, but decreases sharply with further increase of voltage modulation factor for a particular junction temperature; while the same parameter increases with the increase of junction temperature for a particular voltage modulation factor. Heat sinks made of copper and type-IIA diamond are designed to carry out the steady-state and transient thermal analysis of the device operating in CW and pulsed modes respectively. Authors have adopted Olson＇s method to carry out the transient analysis of the device, which clearly establishes the superiority of type-IIA diamond over copper as the heat sink material of the device from the standpoint of the undesirable effect of frequency chirping due to thermal transients in the pulsed mode.

关键词： admittance characteristics chirp bandwidth frequency chirping junction temperature large-signal analysis transient thermal analysis

Shark scavenging behavior in the presence of competition

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Current Zoology 2010年第1期56卷 100-108页

作者： Shannon p.GERRY Andrea j.SCOTT Department of Biological Sciences University of Rhode Island Department of Biological Sciences Wellesley College

The distribution of organisms within a community can often be determined by the degree of plasticity or degree of specialization of resource acquisition. Resource acquisition is often based on the morphology of an organism, behavior, or a combination of both. performance tests of feeding can identify the possible interactions that allow one species to better exploit a prey item. Scavenging behaviors in the presence or absence of a competitor were investigated by quantifying prey selection in a trophic generalist, spiny dogfish Squalus acanthias, and atrophic specialist, smooth-hounds Mustelus canis, in order to determine if each shark scavenged according to its jaw morphology. The diet of dogfish consists of small fishes, squid, ctenophores, and bi- valves; they are expected to be nonselective predators. Smooth-hounds primarily feed on crustaceans; therefore, they are predicted to select crabs over other prey types. prey selection was quantified by ranking each prey item according to the order it was consumed. Dietary shifts were analyzed by comparing the percentage of each prey item selected during solitary versus competitive scavenging. When scavenging alone, dogfish prefer herring and squid, which are easily handled by the cutting dentition of dogfish. Dogfish shift their diet to include a greater number of prey types when scavenging with a competitor. Smooth-hounds scavenge on squid, herring, and shrimp when alone, but increase the number of crabs in the diet when scavenging competitively. Competition causes smooth-hounds to scavenge according to their jaw morphology and locomotor abilities, which enables them to feed on a specialized resource [Current Zoology 56 （1）： 100-108 2010].

关键词： Optimal foraging theory prey selection Squalus acanthias Mustelus canis

potentiality of semiconducting diamond as the base material of millimeter-wave and terahertz IMpATT devices

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journal of Semiconductors 2014年第3期35卷 39-49页

作者： Aritra Acharyya Suranjana Banerjee j.p.Banerjee Institute of Radio physics and Electronics University of Calcutta Academy of Technology West Bengal University of Technology

An attempt is made in this paper to explore the potentiality of semiconducting type-IIb diamond as the base material of double-drift region（DDR） impact avalanche transit time（IMpATT） devices operating at both millimetre-wave（mm-wave） and terahertz（THz） frequencies. A rigorous large-signal（L-S） simulation based on the non-sinusoidal voltage excitation（NSVE） model developed earlier by the authors is used in this study. At first,a simulation study based on avalanche response time reveals that the upper cut-off frequency for DDR diamond IMpATTs is 1.5 THz, while the same for conventional DDR Si IMpATTs is much smaller, i.e. 0.5 THz. The L-S simulationresultsshowthattheDDRdiamondIMpATTdevicedeliversapeakRFpowerof7.79Wwithan18.17%conversion efficiency at 94 GHz; while at 1.5 THz, the peak power output and conversion efficiency decrease to6.19mWand8.17%respectively,taking50%*** diamond and Si shows that the former excels over the later as regards high frequency and high power performance at both mm-wave and THz frequency bands. The effect of band to band tunneling on the L-S properties of DDR diamond and Si IMpATTs has also been studied at different mm-wave and THz frequencies.

关键词： diamond IMpATTs DDR large-signal simulation millimeter-wave terahertz

Oxygation Enhances Growth,Gas Exchange and Salt Tolerance of Vegetable Soybean and Cotton in a Saline Vertisol

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journal of Integrative plant Biology 2009年第7期51卷 675-688页

作者： Surya p. Bhattarai David j. Midmore Centre for plant and Water Science Department of Molecular and Life SciencesCentral Queensland University

Impacts of salinity become severe when the soil is deficient in oxygen. OxygaUon （using aerated water for subsurface drip irrigation of crop） could minimize the impact of salinity on plants under oxygen-limiting soil environments. pot experiments were conducted to evaluate the effects of oxygation （12% air volume/volume of water） on vegetable soybean （moderately salt tolerant） and cotton （salt tolerant） in a salinized vertisol at 2, 8, 14, 20 dS/m ECe. In vegetable soybean, oxygation increased above ground biomass yield and water use efficiency （WUE） by 13% and 22%, respectively, compared with the control. Higher yield with oxygation was accompanied by greater plant height and stem diameter and reduced specific leaf area and leaf Na^＋ and CI^- concentrations. In cotton, oxygation increased lint yield and WUE by 18% and 16%, respectively, compared with the control, and was accompanied by greater canopy light interception, plant height and stem diameter. Oxygation also led to a greater rate of photosynthesis, higher relative water content in the leaf, reduced crop water stress index and lower leaf water potential. It did not, however, affect leaf Na^＋ or CI^- concentration. Oxygation invariably increased, whereas salinity reduced the K^＋： Na^＋ ratio in the leaves of both species. Oxygation improved yield and WUE performance of salt tolerant and moderately tolerant crops under saline soil environments, and this may have a significant impact for irrigated agriculture where saline soils pose constraints to crop production.

关键词： cotton irrigation light interception oxygation saline soil salt exclusion stem diameter vegetable soybean

Structure-function Aspects of Extracellular Leucine-rich Repeat-containing Cell Surface Receptors in plants

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journal of Integrative plant Biology 2013年第12期55卷 1212-1223页

作者： Zhao Zhang Bart p.H.j.Thomma Laboratory of phytopathology Wageningen University Centre for BioSystems Genomics

plants exploit several types of cell surface receptors for perception of extracellular signals, of which the extracellular leucine-rich repeat （eLRR）-containing receptors form the major class. Although the function of most plant eLRR receptors remains unclear, an increasing number of these receptors are shown to play roles in innate immunity and a wide variety of developmental processes. Recent efforts using domain swaps, gene shuffling analyses, site-directed mutagenesis, interaction studies, and crystallographic analyses resulted in the current knowledge on ligand binding and the mechanism of activation of plant eLRR receptors. This review provides an overview of eLRR receptor research, specificallysummarizing the recent understanding of interactions among plant eLRR receptors, their co-receptors and corresponding ligands. The functions of distinct eLRR receptor domains, and their role in structure, ligand perception and multimeric complex formation are discussed.

关键词： eLRR receptor-like kinase (RLK) receptor-like protein (RLp) pathogen-associated molecular pattern (pAMp) effector peptide ligand brassinosteroid CLE peptide.

Solving the Dyson-Schwinger equation around its first singularities in the Borel plane

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Frontiers of physics 2016年第6期11卷 25-30页

作者： Clavier, pierre j. Bellon, Marc p. Sorbonne Universites UPMC Univ Paris 06 UMR 7589 LPTHE Paris France CNRS UMR 7589 LPTHE Paris France

The Dyson-Schwinger equation of the massless Wess-Zumino model is written as an equation over the anomalous dimension of the theory. Its asymptotic behavior is derived and the procedure to compute the perturbations of this asymptotic behavior is detailed. This procedure uses ill-defined objects. To solve this, the Dyson-Schwinger equation is rewritten for the Borel plane. It is shown that the ill- defined procedure in the physical plane can be applied in the Borel plane. Other results obtained in the Borel plane are stated and the proof for one result is described.

关键词： Dyson-Schwinger equation Wess-Zumino model Borel transform

The supernova remnant CTB 37B and its associated magnetar CXOU j171405.7-381031:evidence for a magnetar-driven remnant

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Research in Astronomy and Astrophysics 2011年第6期11卷 625-630页

作者： j.E.Horvath M.p.Allen Instituto de Astronomia Geofísica e Ciências Atmosféricas-Universidade de So PauloRua do Mato122605508-900 Cidade Universitria So Paulo SPBrazil CEFET So paulo Rua Pedro Vicente 62501109-010Caninde'So Paulo SPBrazil

We discuss the association between the candidate magnetar CXOU j171405.7-381031 and the supernova remnant CTB *** recent detection of the period derivative of the object allowed an estimation of a young characteristic age of only ～ *** value is too small to be compatible even with the minimum radius of the remnant being ≥ 10 pc,the value corresponding to the lower limit of the estimated distance of 10.2 ± 3.5 kpc,unless the true distance happens to be even smaller than the lower *** argue that a consistent scenario for the remnant＇s origin,in which the latter is powered by the energy injected by a young magnetar,is indeed more accurate to explain the young age,and demonstrates its non-standard（***-driven） nature.

关键词： stars:supernova — stars:neutron

Spiking neural p systems with neuron division and budding

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Science China(Information Sciences) 2011年第8期54卷 1596-1607页

作者： p■UN Gheorghe pREZ-jIMNEZ Mario j. Department of Computer Science and Artificial Intelligence University of Sevilla Avda Reina Mercedes s/n 41012 Sevilla Spain Institute of Mathematics of the Romanian Academy pO Box 1-764 014700 Bucuresti Romania

Spiking neural p systems are a class of distributed and parallel computing models inspired by spiking *** this work,the features of neuron division and neuron budding are introduced into the framework of spiking neural p systems,which are processes inspired by neural stem cell division. With neuron division and neuron budding,a spiking neural p system can generate exponential work space in polynomial time as the case for p systems with active *** this way,spiking neural p systems can efficiently solve computationally hard problems by means of a space-time tradeoff,which is illustrated with an efficient solution to SAT problem.

关键词： natural computing membrane computing spiking neural p system neuron division

Nilsson mean-field plus the extended pairing model description of rare earth nuclei

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Chinese physics C 2011年第8期35卷 747-752页

作者：关鑫李杭谭奇潘峰 j.p.Draayer Department of physics Liaoning Normal University Department of physics and Astronomy Louisiana State University

The Nilsson mean-field plus the extended pairing model for well-deformed nuclei is applied to some representative rare earth examples. The binding energies, some low-lying pair-excited states and evenodd mass differences of Er, Yb and Hf isotopes are calculated systematically within the proton frozen-pair excitation limit. A comparison with experimental data for these nuclei shows that the results of the extended pairing model are better than those for the standard pairing model with the BCS approximation and the nearest-orbit pairing model.

关键词： Nilsson mean-field pairing interaction binding energy even-odd mass difference