Effects of thermal conduction in sonoluminescence

We show by numerical hydrodynamic calculations that there are two important effects of thermal conduction in sonoluminescence: (i) the bubble remains close to being isothermal during the expansion phase; and (ii) a cold, dense layer of air is formed at the bubble wall during the contraction phase. These conclusions are not sensitive to the particular equation of state used, although details of the dynamical evolution of the bubble are

Type I superconductivity in the Dirac semimetal PdTe2

The superconductor PdTe$_2$ was recently classified as a Type II Dirac semimetal, and advocated to be an improved platform for topological superconductivity. Here we report magnetic and transport measurements conducted to determine the nature of the superconducting phase. Surprisingly, we find that PdTe$_2$ is a Type I superconductor with $T_c = 1.64$ K and a critical field $\mu_0 H_c (0) = 13.6$ mT. Our crystals also exhibit the intermediate state as demonstrated by the differential paramagnetic effect. For $H > H_c$ we observe superconductivity of the surface sheath. This calls for a close examination of superconductivity in PdTe$_2$ in view of the presence of topological surface states.Comment: 5 page

Muon spin rotation study of the topological superconductor SrxBi2Se3

We report transverse-field (TF) muon spin rotation experiments on single crystals of the topological superconductor Sr$_x$Bi$_2$Se$_3$ with nominal concentrations $x=0.15$ and $0.18$ ($T_c \sim 3$ K). The TF spectra ($B= 10$ mT), measured after cooling to below $T_c$ in field, did not show any additional damping of the muon precession signal due to the flux line lattice within the experimental uncertainty. This puts a lower bound on the magnetic penetration depth $\lambda \geq 2.3 ~\mu$m. However, when we induce disorder in the vortex lattice by changing the magnetic field below $T_c$ a sizeable damping rate is obtained for $T \rightarrow 0$. The data provide microscopic evidence for a superconducting volume fraction of $\sim 70~ \%$ in the $x=0.18$ crystal and thus bulk superconductivity.Comment: 6 pages, includes 4 figure

State detection using coherent Raman repumping and two-color Raman transfers

We demonstrate state detection based on coherent Raman repumping and a two-color Raman state transfer. The Raman coupling during detection selectively eliminates unwanted dark states in the fluorescence cycle without compromising the immunity of the desired dark state to off-resonant scattering. We demonstrate this technique using $^{137}\mathrm{Ba}^+$ where a combination of Raman coupling and optical pumping leaves the $D_{3/2}$ $\ket{F"=3,m_F"=3}$ metastable state optically dark and immune to off-resonant scattering. All other states are strongly coupled to the upper $P_{1/2}$ levels. We achieve a single shot state-detection efficiency of $89.6(3)$ in a $1\mathrm{ms}$ integration time, limited almost entirely by technical imperfections. Shelving to the $\ket{F"=3,m_F"=3}$ state before detection is performed via a two-color Raman transfer with a fidelity of $1.00(3)$

Classification of Overlapped Audio Events Based on AT, PLSA, and the Combination of Them

Audio event classification, as an important part of Computational Auditory Scene Analysis, has attracted much attention. Currently, the classification technology is mature enough to classify isolated audio events accurately, but for overlapped audio events, it performs much worse. While in real life, most audio documents would have certain percentage of overlaps, and so the overlap classification problem is an important part of audio classification. Nowadays, the work on overlapped audio event classification is still scarce, and most existing overlap classification systems can only recognize one audio event for an overlap. In this paper, in order to deal with overlaps, we innovatively introduce the author-topic (AT) model which was first proposed for text analysis into audio classification, and innovatively combine it with PLSA (Probabilistic Latent Semantic Analysis). We propose 4 systems, i.e. AT, PLSA, AT-PLSA and PLSA-AT, to classify overlaps. The 4 proposed systems have the ability to recognize two or more audio events for an overlap. The experimental results show that the 4 systems perform well in classifying overlapped audio events, whether it is the overlap in training set or the overlap out of training set. Also they perform well in classifying isolated audio events

A Comparative Study of Current and Potential Users of Mobile Payment Services

Previous studies of mobile payment (m-payment) services have primarily focused on a single group of adopters. This study identifies the factors that influence an individual’s intention to use m-payment services and compares groups of current users (adopters) with potential users (non-adopters). A research model that reflects the behavioral intention to use m-payment services is developed and empirically tested using structural equation modeling on a data set consisting of 529 potential users and 256 current users of m-payment services in Thailand. The results show that the factors that influence current users’ intentions to use m-payment services are compatibility, subjective norms, perceived trust, and perceived cost. Subjective norms, compatibility, ease of use, and perceived risk influenced potential users’ intentions to use m-payment. Subjective norms and perceived risk had a stronger influence on potential users, while perceived cost had a stronger influence on current users, in terms of their intentions to use m-payment services. Discussions, limitations, and recommendations for future research are addressed

Kinetic modeling of electro-Fenton reaction in aqueous solution

Author name used in this publication: H. LiuAuthor name used in this publication: X. Z. LiAuthor name used in this publication: Y. J. LengAuthor name used in this publication: C. Wang2006-2007 > Academic research: refereed > Publication in refereed journalAccepted ManuscriptPublishe

Evaluating the Role of Trust in Consumer Adoption of Mobile Payment Systems: An Empirical Analysis

Consumer adoption of mobile payment (m-payment) solutions is low compared to the acceptance of traditional forms of payments. Motivated by this fact, we propose and test a “trust-theoretic model for consumer adoption of m-payment systems.” The model, grounded in literature on “technology adoption” and “trust,” not only theorizes the role of consumer trust in m-payment adoption, but also identifies the facilitators for consumer trust in m-payment systems. It proposes two broad dimensions of trust facilitators: “mobile service provider characteristics” and “mobile technology environment characteristics.” The model is empirically validated via a sample of potential adopters in Singapore. In contrast to other contexts, results suggest the overarching importance of “consumer trust in m-payment systems” as compared to other technology adoption factors. Further, differential importance of the theorized trust facilitators of “perceived reputation” and “perceived opportunism” of the mobile service provider, and “perceived environmental risk” and “perceived structural assurance” of the mobile technology, are also highlighted. A series of post-hoc analyses establish the robustness of the theorized configuration of constructs. Subsequent, sub-group analyses highlight the differential significance of trust facilitators for different user sub-groups. Implications for research and practice emerging out of this study are also discussed