Explicit formulas for effective piezoelectric coefficients of ferroelectric 0-3 composites based on effective medium theory

Author name used in this publication: C. K. WongAuthor name used in this publication: Y. M. PoonAuthor name used in this publication: F. G. Shin2002-2003 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Dielectric response of spherically anisotropic graded piezoelectric composites

Author name used in this publication: Y. M. PoonAuthor name used in this publication: F. G. Shin2007-2008 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Dielectric and pyroelectric properties of lead zirconate titanate/polyurethane composties

Author name used in this publication: K. S. LamAuthor name used in this publication: Y. W. WongAuthor name used in this publication: L. S. TaiAuthor name used in this publication: Y. M. PoonAuthor name used in this publication: F. G. Shin2004-2005 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

On the Changing Role of the Stratosphere on the Tropospheric Ozone Budget: 1979–2010

We study the evolution of tropospheric ozone over the period 1979-2010 using a chemistry-climate model employing a stratosphere-troposphere chemistry scheme. By running with specified dynamics, the key feedback of composition on meteorology is suppressed, isolating the chemical response. By using historical forcings and emissions, interactions between processes are realistically represented. We use the model to assess how the ozone responds over time and to investigate model responses and trends. We find that the CFC-driven decrease in stratospheric ozone plays a significant role in the tropospheric ozone burden. Over the period 1979-1994, the decline in transport of ozone from the stratosphere, partially offsets an emissions-driven increase in tropospheric ozone production. From 1994-2010, despite a levelling off in emissions increased stratosphere-to-troposphere transport of ozone drives a small increase in the tropospheric ozone burden. These results have implications for the impact of future stratospheric ozone recovery on air quality and radiative forcing.European Community’s Seventh Framework Programme 10 (FP7/2007-2013) under grant agreement no. 603557 (StratoClim)

Temperature dependence of the complex effective piezoelectric coefficient of ferroelectric 0-3 composites

Author name used in this publication: C. K. WongAuthor name used in this publication: Y. M. PoonAuthor name used in this publication: F. G. Shin2002-2003 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Effective properties of piezoelectric composites with periodic structure

Author name used in this publication: F. G. Shin2006-2007 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Effective properties of spherically anisotropic piezoelectric composites

Author name used in this publication: Y. M. PoonAuthor name used in this publication: F. G. Shin2007-2008 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

First measurement of the T-violating muon polarization in the decay K^+ --> mu^+ nu gamma

We present the result of the first measurement of the T-violating muon polarization P_T in the decay K^+ --> mu^+ nu gamma. This polarization is sensitive to new sources of CP-violation in the Higgs sector. Using data accumulated in the period 1996-98 we have obtained P_T = (-0.64 +- 1.85(stat) +- 0.10(syst))x10^{-2} which is consistent with no T-violation in this decay.Comment: 11 pages, 8 figure

Chemistry-driven changes strongly influence climate forcing from vegetation emissions

Biogenic volatile organic compounds (BVOCs) affect climate via changes to aerosols, aerosol-cloud interactions (ACI), ozone and methane. BVOCs exhibit dependence on climate (causing a feedback) and land use but there remains uncertainty in their net climatic impact. One factor is the description of BVOC chemistry. Here, using the earth-system model UKESM1, we quantify chemistry’s influence by comparing the response to doubling BVOC emissions in the pre-industrial with standard and state-of-science chemistry. The net forcing (feedback) is positive: ozone and methane increases and ACI changes outweigh enhanced aerosol scattering. Contrary to prior studies, the ACI response is driven by cloud droplet number concentration (CDNC) reductions from suppression of gas-phase SO2 oxidation. With state-of-science chemistry the feedback is 43% smaller as lower oxidant depletion yields smaller methane increases and CDNC decreases. This illustrates chemistry’s significant influence on BVOC’s climatic impact and the more complex pathways by which BVOCs influence climate than currently recognised