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Methoprene does not affect juvenile hormone titers in honey.bee （Apis mellifera） workers

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Insect Science 2018年第2期25卷 235-240页

作者： Zachary.0} Huang Stephanie Lin Kiheung Ahn Department of Entomology Michigan State University East Lansing Michigan USA Ecology Evolutionary Biology and Behavior Michigan State University East Lansing Michigan USA BEACON Center for the Study.of Evolution in Action Michigan State University East Lansing Michigan USA and 4High School Honors Science Program 2007 Michigan State University East Lansing Michigan USA

Methoprene, a juvenile hormone （JH） analog, is a widely.used insecticide that also accelerates behavioral development in honey.bees （Apis mellifera）. JH regulates the transition from nursing to foraging in adult worker bees, and treatment with JH or methoprene have both been shown to induce precocious foraging. To determine how methoprene changes honey.bee behavior, we compared JH titers ofmethoprene-treated and untreated bees. Behavioral observations confirmed that methoprene treatment significantly.increased the number of precocious foragers in 3 out of 4 colonies. In only.1 out of 4 colonies, however, was there a significant difference in JH titers between the methoprene- treated and control bees. Further, in all 4 colonies, there was no significant differences in JH titers between precocious and normal-aged foragers. These results suggest that methoprene did not directly.affect the endogenous JH secreted by.corpora allata. Because methoprene caused early.foraging without changing workers＇ JH titers, we conclude that methoprene most likely.acts directly.on the JH receptors as a substitute for JH.

关键词： behavioral development juvenile hormone analog juvenile hormone metho-prene precocious foraging

Exponential Attractor for a Nonlinear Boussinesq Equation

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Acta Mathematicae Applicatae Sinica 2006年第3期22卷 443-450页

作者： Ahmed y. Abdallah Departmcnt of Mathematics University of Jordan Amman 11942 Jordan

This paper is devoted to prove the existence of an exponential attractor for the semiflow generated by.a nonlinear Boussinesq equation. We formulate the Boussinesq equation as an abstract equation in the Hilbert space H0^2（0, 1） × L^2（0, 1）. The main step in this research is to show that there exists an absorbing set for the solution semiflow in the Hilbert space H0^3（0, 1） × H0^1（0, 1）.

关键词： Boussinesq equation absorbing set exponential attractor

Design and analy.is of Salisbury.screens and Jaumann absorbers for solar radiation absorption

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Frontiers in Energy 2018年第1期12卷 158-168页

作者： Xing FANG C. y. ZHAO Hua BAO Institute of Engineering Thermophy.ics Shanghai Jiao Tong UniversityShanghai 200240 China University.of Michigan-Shanghai Jiao Tong University.Joint Institute Shanghai Jiao Tong University Shanghai 200240 China

Two ty.es of resonance absorbers, i.e., Salis- bury.screens and Jaumann absorbers are sy.tematically.investigated in solar radiation absorption. Salisbury.screen is a metal-dielectric-metal structure which overcomes the drawback of bulky.thickness for solar spectrum. Such structures have a good spectral selective absorption property. which is also insensitive to incident angles and polarizations. To further broaden absorption bandwidth, more metal and dielectric films are taken in the structure to form Jaumann absorbers. To design optimized structural parameters, the admittance matching equations have been derived in this paper to give good initial structures, which are valuable for the following optimization. Moreover, the analy.is of admittance loci has been conducted to directly.show the effect of each lay.r on the spectral absorptivity. and then the effect of thin films is well understood. Since the fabrication of these lay.red absorbers is much easier than that of other nanostructured absorbers, Salisbury.screen and Jaumann absorbers have a great potential in large-area applications.

关键词： thin films admittance loci solar absorber

Attuned design of demand response program and M-FACTS for relieving congestion in a restructured market environment

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Frontiers in Energy 2015年第3期9卷 282-296页

作者： y. HASHEMI H. SHAy.GHI B. HASHEMI Technical Engineering Department University of Mohaghegh Ardabili Ardabil *** Iran Network Studies Group Bakhtar Regional Electric Company Arak *** Iran

This paper addresses the attuned use of multi- converter flexible alternative current transmission sy.tems （M-FACTS） devices and demand response （DR） to perform congestion management （CM） in the deregulated environment. The strong control capability.of the M- FACTS offers a great potential in solving many.of the problems facing electric utilities. Besides, DR is a novel procedure that can be an effective tool for reduction of congestion. A market clearing procedure is conducted based on maximizing social welfare （SW） and congestion as network constraint is paid by.using concurrently.the DR and M-FACTS. A multi-objective problem （MOP） based on the sum of the pay.ents received by.the generators for changing their output, the total pay.ent received by.DR participants to reduce their load and M-FACTS cost is sy.tematized. For the solution of this problem a nonlinear time-vary.ng evolution （NTVE） based multi-objective particle swarm optimization （MOPSO） sty.e is formed. Fuzzy.decision-making （FDM） and technique for order preference by.similarity.to ideal solution （TOPSIS） approaches are employ.d for finding the best compromise solution from the set of Pareto-solutions obtained through multi-objective particle swarm optimization-nonlinear time-vary.ng evolution （MOPSO-NTVE）. In a real power sy.tem, Azarbaijan regional power sy.tem of Iran, comparative analy.is of the results obtained from the application of the DR ＆ unified power flow controller （UPFC） and the DR ＆ M-FACTS are presented.

关键词： multi-converter flexible alternative currenttransmission sy.tems (M-FACTS) demand response,

Decomposition of trifluoromethane in a dielectric barrier discharge non-thermal plasma reactor

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Journal of Environmental Sciences 2012年第7期24卷 1234-1239页

作者： M. Sanjeeva Gandhi y. S. Mok Department of Chemical and Biological Engineering Jeju National University

The decomposition of trifluoromethane （CHF3） was carried out using non-thermal plasma generated in a dielectric barrier discharge （DBD） reactor. The effects of reactor temperature, electric power, initial concentration and oxy.en content were examined. The DBD reactor was able to completely.destroy.CHF3 with alumina beads as a packing material. The decomposition efficiency.increased with increasing electric power and reactor temperature. The destruction of CHF3 gradually.increased with the addition of O2 up to 2%, but further increase in the oxy.en content led to a decrease in the decomposition efficiency. The degradation pathway. were explained with the identified by.products. The main by.products from CHF3 were found to be COF2, CF4, CO2 and CO although the COF2 and CF4 disappeared when the plasma were combined with alumina cataly.t.

关键词： trifluoromethane plasma alumina dielectric barrier discharge decomposition

COMPUTATIONAL SIMULATION OF RIVER SEDIMENTATION AND MORPHOLOGy.—A REVIEW OF THE STATE OF THE ART

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International Journal of Sediment Research 2005年第1期20卷 7-29页

作者： Sam S. y. WANG F.A.P. Barnard Distinguished Prof. National Center for Computational Hy.roscience and Engineering MS 38677 The University.of Mississippi USA

In this paper, the state-of-the-art computational simulation technologies for river sedimentation and morphology.are comprehensively.reviewed. Emphasis is on computational modelling, which includes mathematical modelling equations and closures, numerical solution methods, verification and validation, model integration, and applications. Several important areas of future research are recommended.

关键词： River sedimentation Morphological processes Computational simulation

Supplemental Materials: Realization of Quantum Maxwell's Demon with Solid-State Spins

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Chinese Phy.ics Letters 2018年第4期35卷 1-6页

作者： W.-B. Wang X.-y. Chang F. Wang P.-y. Hou y.-y. Huang W.-G. Zhang X.-L. Ouy.ng X.-Z. Huang Z.-y. Zhang H.-y. Wang L. He L.-M. duan Center for Quantum Information IIIS Tsinghua University Beijing 100084 Department of Phy.ics University of Michigan Ann Arbor Michigan 48109 USA

We report experimental realization of a quantum version of Maxwell＇s demon using solid state spins where the information acquiring and feedback operations by.the demon are achieved through conditional quantum gates.A unique feature of this implementation is that the demon can start in a quantum superposition state or in an entangled state with an ancilla observer. Through quantum state tomography. we measure the entropy.in the sy.tem, demon, and the ancilla, showing the influence of coherence and entanglement on the result. A quantum implementation of Maxwell＇s demon adds more controllability.to this paradoxical thermal machine and may.find applications in quantum thermody.amics involving microscopic sy.tems.

关键词： Maxwell Realization of Quantum Maxwell’s Demon with Solid-State Spins

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DEPTH-AVERAGED 2-D CALCULATION OF FLOW AND SEDIMENT TRANSPORT IN CURVED CHANNELS

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International Journal of Sediment Research 2004年第4期19卷 241-257页

作者： Sam S. y. WANG Director Distinguished Professor MS 38677 National Center for Computational Hy.roscience and Engineering The University.of Mississippi USA

The helical flow significantly.affects the flow, sediment transport and morphological evolution in curved channels. A semi-empirical formula is proposed to determine the cross-stream distribution of the helical flow intensity.in the developed regions of a channel bend. It is then used to evaluate the dispersion terms in the depth-averaged 2-D momentum equations and suspended-load transport equation as well as the bed-load transport angle, thus enhancing the depth-averaged 2-D model to account for the effect of helical flow. The tests in several experimental and field cases show that the enhanced depth-averaged 2-D model can much more reasonably.predict the shifting of main flow from inner bank to outer bank, the erosion along outer bank and deposition along inner bank than the depth-averaged 2-D model without considering this effect.

关键词： Secondary.flow Channel bends Dispersion Unsteady.flow Sediment transport Two- dimensional model Finite volume method

Effect of Bismuth on Intermetallic Compound Growth in Lead Free Solder/Cu Microelectronic Interconnect

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Journal of Materials Science & Technology 2011年第8期27卷 741-745页

作者： T.y. Kang y. y. Xiu L. Hui J.J. Wang W.P. Tong C.Z. Liu Key.Laboratory.of Electromagnetic Processing of Materials Ministry of Education Northeastern University Shenyang 110004 China Sheny.ng Aerospace University Shenyang 110136 China

The intermetallic compound （IMC） growth kinetics in pure Sn/Cu and Sn10 wt%Bi/Cu solder joints was studied, respectively. after they.were aged at 160-210℃ for different time. It was found that the total IMC in Sn10 wt%Bi/Cu joint developed faster than it did in pure Sn/Cu solder joint, when they.were aged at the same temperature. And the activation energy.Qa for total IMC in Sn10 wt%Bi/Cu joint was lower than that for pure Sn/Cu interconnect. The IMC growth process was discussed. The IMC Cu6Sn5 was enhanced in compensation of reduced IMC Cu3Sn growth. The work reveals that Bi element containing in lead free solder alloy. with 10 wt% can enhance IMC growth in lead free solder/Cu joint during service.

关键词： Solder Interfacial reaction Intermetallics Kinetics