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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.y. 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

Novel poly.thy.eneimine/TMC-based nanofiltration membrane prepared on a poly.opamine coated substrate

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Frontiers of Chemical Science and Engineering 2018年第2期12卷 273-282页

作者： Zhe y.ng Xiaoy. huang Jianqiang Wang Chuy.ng y. Tang Department of Civil Engineering the University of Hong Kong Hong Kong China

Most commercial NF membranes are negatively.charged at the pH range of a ty.ical feed solution. In order to enhance the removal of cations （such as Mg2＋ or Ca2＋）, we utilized poly.thy.eneimine （PEI） and trimesoy. chloride （TMC） to perform interfacial poly.erization reaction on a poly.opamine coated hy.roly.ed poly.cry.lonitrile substrate to obtain a positively.charged nanofiltration membrane. Effects ofpoly.opamine coating time, PEI concentration, TMC reaction time and concentration on the membrane phy.icochemical properties and separation performance were sy.tematically.investigated using scanning electron microscopy. streaming potential and water contact angle measurements. The optimal NF membrane showed high rejection for divalent ions （93.6±2.6% for MgSO4, 92.4±1.3% for MgCl2, and 90.4±2.1% for Na2SO4）, accompanied with NaCl rejection of 27.8±2.5% with a permeation flux of 17.2±2.8 L.m-2.h-1 at an applied pressure of 8 bar （salt concentrations were all 1000 mg.L-1）. The sy.thesized membranes showed promising potentials for the applications of water soft-ening.

关键词： nanofiltration poly.thy.eneimine trimesoy. chloride poly.opamine positively.charged rejection lay.r

Active elastic metamaterials for subwavelength wave propagation control

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Acta Mechanica Sinica 2015年第3期31卷 349-363页

作者： y.y.Chen G.L.huang Department of Mechanical and Aerospace Engineering University of Missouri

Recent research activities in elastic metamaterials demonstrate a significant potential for subwavelength wave propagation control owing to their interior locally.resonant mechanism. The growing technological developments in electro/magnetomechanical couplings of smart materials have introduced a controlling degree of freedom for passive elastic metamaterials. Active elastic metamaterials could allow for a fine control of material phy.ical behavior and thereby.induce new functional properties that cannot be produced by.passive approaches. In this paper, two ty.es of active elastic metamaterials with shunted piezoelectric materials and electrorheological elastomers are proposed. Theoretical analy.es and numerical validations of the active elastic metamaterials with detailed microstructures are pre- sented for designing adaptive applications in band gap structures and extraordinary.waveguides. The active elastic metamaterial could provide a new design methodology.for adaptive wave filters, high signal-to-noise sensors, and structural health monitoring applications.

关键词： Active elastic metamaterials Subwavelengthwave control Adaptive metastructures Smart materials

INVESTIGATION OF MULTI-STEP THERMO-MECHANICALTREATMENT OF CAN-FORGED TiAl-BASED ALLOy

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Acta Metallurgica Sinica(English Letters) 1997年第4期10卷 369-374页

作者： y.H. He B. y. huang y. Liu and y.X. Liu (Powder Metallurgy.Research Institute, Central South University.of Technology. Changsha 410083, China) Central South Univ of Technology Changsha China

The effects of a new technology. multi-step thermo-mechanical treatment, on the microstructure, deformation substructure and mechanical properties at ambient and elevated tempemture of can-forged Ti-33 Al-3 Cr-0.5Mo (wt%) Alloy.were *** results show that, after multi-step thermo-mechanical treatment of can-forged specimens, homogeneous, fine microstructures can be obtained in the whole TiAl-based alloy.specimens. Furthermore, the specimen with homogeneous and fine full lamellae microstructure demonstrutes excellent comprehensive mechanical properties at ambient and elevated temperature.

关键词： TiAl-based alloy mechanical property heat treatment

NUMERICAL MODELING OF SUSPENDED SEDIMENT TRANSPORT IN CHANNEL BENDS

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Journal of Hy.rody.amics 2006年第4期18卷 411-417页

作者： huang Sui-liang JIAy.F,WANG Sam S. y. College of Environmental Science and Engineering Nankai University Tianjin 300071 China National Center for Computational Hy.roscience and Engineering The University of Mississippi Oxford USA

An algorithm to compute three-dimensional sediment transport effect was proposed in this paper to enhance the capability.of depth-averaged numerical models. This algorithm took into account of non-uniform distributions of flow velocities and suspended sediment concentrations along water depth, it significantly.enhanced the applicability.of 2D models in simulating open channel flows, especially.in channel bends. Preliminary.numerical experiments in a U-shaped and a sine-generated experimental channel indicate that the proposed method performs quite well in predicting the change of bed-deformation in channel bends due to suspended sediment transport. This method provides an effective alternative for the simulations of channel morphody.amic changes.

关键词： algorithm dispersion terms bends suspended sediment transport 2D numerical model

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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A COMPREHENSIVE MODEL OF LASER CLADDING By.POWDER FEEDING

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Acta Metallurgica Sinica(English Letters) 2004年第1期17卷 21-27页

作者： y.L.huang G.y.Liang J.y.Su School of Materials Science and Engineering Xi'an Jiaotong University Xi'an 710049 ChinaSchool of Materials Science and Engineering Xi'an Jiaotong University Xi'an 710049 ChinaSchool of Materials Science and Engineering Xi'an Jiaotong University Xi'an 710049 China

A novel model was presented to predict the evolutionary.development of cladding lay.r, and a method based on Lambert-Beer theorem and Mie's theory.was adopted to treat the interaction between powder stream and laser beam. By.using the continuum model and enthalpy.porosity.method, the fluid flow and heat transfer in solid-liquid phase change sy.tem were simulated. The commercial software PHOENICS, to which several modules were appended, was used to accomplish the simulation. Numerical computation was performed for Stellite 6 cladding on steel, the obtained results are coincident with those measured in experiment basically.

关键词： laser cladding powder feeding cladding lay.r interaction

NUMERICAL SIMULATION OF 3-D CORNER FLOWS IN A CIRCULATING WATER CHANNEL

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Journal of Hy.rody.amics 2001年第2期13卷 63-67页

作者： huang, y. Wang, G.Q. Tamashima, M. Shanghai Jiaotong Univ. Shanghai 200030 China

A Navier-Stokes procedure was developed based on a finite volume method to simulate corner flows in circulating water channel (CWC). The standard 2nd-order central scheme together with a deferred correction method was applied for the convective terms. All the other terms were discretized using 2nd order central differencing. The standard k-Ε model was used for the approximation of turbulent flows. First, this method used to calculate the turbulent flows in a 90° bend and the computed results are in good agreements with the experiment. This method was also employ.d to calculate the flows in a model CWC corner.

关键词： Computational fluid dy.amics Computer simulation Finite volume method Laminar flow Navier Stokes equations Three dimensional Turbulent flow

WAVE RESISTANCE OF WAVE-PIERCING CATAMARANS

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Journal of Hy.rody.amics 2000年第4期12卷 88-98页

作者： Lu, X.P. huang, y. Shi, Z.K. Coll. of Traffic Sci. and Eng. Huazhong Univ. of Sci. and Technol. Wuhan 430074 China

Present paper researches the theoretical method for calculating the wave resistance of wave-piercing catamaran. As an example the wave resistance of a wave-piercing catamaran is calculated. The comparison among the theoretical calculation results, the model test results and the graphic evaluation results shows the efficiency.of present theoretical method. Finally.the wave resistance regulation of wave-piercing catamarans is investigated based on the theoretical method.

关键词： Ships