Weighted estimates for powers and smoothing estimates of Schrödinger operators with inverse-square potentials

Let \La be a Schr\"odinger operator with inverse square potential $a|x|^{-2}$ on \Rd, d\geq 3. The main aim of this paper is to prove weighted estimates for fractional powers of \La. The proof is based on weighted Hardy inequalities and weighted inequalities for square functions associated to \La. As an application, we obtain smoothing estimates regarding the propagator e^{it\La}

Weighted estimates for powers and smoothing estimates of Schrödinger operators with inverse-square potentials

Let \La be a Schr\"odinger operator with inverse square potential $a|x|^{-2}$ on \Rd, d\geq 3. The main aim of this paper is to prove weighted estimates for fractional powers of \La. The proof is based on weighted Hardy inequalities and weighted inequalities for square functions associated to \La. As an application, we obtain smoothing estimates regarding the propagator e^{it\La}

Exposure to hazardous volatile organic compounds, PM 10 and CO while walking along streets in urban Guangzhou, China

Toxic air pollutants in street canyons are important issues concerning public health especially in some large Asian cities like Guangzhou. In 1998 <18% of Guangzhou citizens used public transportation modes, with a majority commuting on foot (42%) or by bicycle (22%). Of the pedestrians, 57% were either senior citizens or students. In the present study, we measured toxic air pollutants while walking along urban streets in Guangzhou to evaluate pedestrian exposure. Volatile organic compounds (VOCs) were collected with sorbent tubes, and PM 10 and CO were measured simultaneously with portable analyzers. Our results showed that pedestrian exposure to PM 10 (with an average of 303 μg m -3 for all samples) and some toxic VOCs (for example, benzene) was relatively high. Monocyclic aromatic hydrocarbons were found to be the most abundant VOCs, and 71% of the samples had benzene levels higher than 30 μg m -3. Benzene, PM 10 and CO in walk-only streets were significantly lower (p<0.05) than in traffic streets, and the differences in exposure levels between new urban streets and old urban streets were highly significant (p<0.01). Pedestrian exposure to toxic VOCs and PM 10 was higher than those reported in other public transportation modes (bus and subway). The good correlations between BTEX, PM 10 and CO in the streets indicated that automotive emission might be their major source. Our study also showed that the risk to pedestrians due to air pollution was misinterpreted by the reported air quality index based on measurement of SO 2, NO x and PM 10 in the government monitoring stations. An urban roadside monitoring station might be needed by air quality monitoring networks in large Asian cities like Guangzhou, in order to survey exposure to air toxics in urban roadside microenvironments. © 2004 Elsevier Ltd. All rights reserved

A reconfigurable beam-scanning partially reflective surface (PRS) antenna

© 2015 EurAAP. A novel reconfigurable partially reflective surface (PRS) antenna is presented in this paper. The beam scanning ability is realized by employing a reconfigurable PRS structure and a phased array as the source. The design achieves a beam switching between -15°, 0°, to 15° with respect to the broadside direction from 5.5 GHz to 5.7 GHz with the realized gains over 12 dBi. Good agreement between the simulated and measured results is achieved

A wideband polarization reconfigurable antenna for WLAN applications

© 2016 European Association of Antennas and Propagation. This paper proposes a wideband polarization reconfigurable antenna design for WLAN applications. It consists of a shorted annular patch (SAP) antenna as the source, a partially reflective surface (PRS) structure to enhance the gain, and a reconfigurable Wilkinson power divider as the feed network. The antenna can electronically alter its polarization between linear polarization (LP), left-hand circular polarization (LHCP), and right-hand circular polarization (RHCP),achieving an overlapped 10dB impedance bandwidth and 3 dB axial-ratio bandwidth of 4.68-5.33 GHz (13%), thus outperforming most of the reported polarization reconfigurable antennas in terms of the frequency bandwidth

Precipitation of PEG/Carboxyl-modified gold nanoparticles with magnesium pyrophosphate : a new platform for real-time monitoring of loop-mediated isothermal amplification

2016-2017 > Academic research: refereed > Publication in refereed journal201804_a bcmaVersion of RecordRGCOthersRGC: 501413Others: PGMS Project IDs: P0009500 and P0009150Publishe