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Global Competition, Institutions, And The Diffusion Of Organizational Practices: The International Spread Of Iso 9000 Quality Certificates
We use panel data on ISO 9000 quality certification in 85 countries between 1993 and 1998 to better understand, the cross-national diffusion of an organizational practice. Following neoinstitutional theory, we focus on the coercive, normative, and mimetic effects that result from the exposure of firms in a given country to a powerful source of critical resources, a common pool of relevant technical knowledge, and the experiences of firms located in other countries. We use social network theory to develop a systematic conceptual understanding of how firms located in different countries influence each other's rates of adoption as a result of cohesive and equivalent network relationships. Regression results provide support for our predictions that states and foreign multinationals are the key actors responsible for coercive isomorphism, cohesive trade relationships between countries generate coercive and normative effects, and role-equivalent trade relationships result in learning-based and competitive imitation.Business Administratio
production rate measurement in neutrino interactions and a limit on muon neutrino to tau neutrino oscillations
The CHORUS experiment was designed to search for \nu_\mu---> \nu_\tau oscillations. Recently, Phase I analysis has been completed and no \tau candidate is found. The second phase of the CHORUS analysis was recently started with new scanning systems. The big improvements in the scanning system and methods allow the CHORUS experiment to study also charm physics with large statistics. In this work, D^0 production rate in neutrino charged-current interactions has been evaluated using 122 D^0 candidates found in 8028 located \nu_\mu charged-current interactions in the collaboration, as; \sigma(\nu_mu N--> D^0\mu^-X)/sigma(\nu_mu N--> \mu^-X)= 1.998 \pm 0.223%. The achived precision of the production rate exceeds that of the previous experiments
OPERA neutrino oscillation results
The OPERA experiment was designed to perform the first detection of νμ → ντ neutrino oscillations in a direct appearance mode. We present the analysis results of the 2008–2009 statistics corresponding to 4.88 × 1019 p.o.t. In this sample, one ντ candidate event has been observed in the τ → h channel. The statistical significance of this observation is estimated to be 95%
Colloidal Plasmonic Titanium Nitride Nanoparticles: Properties and Applications
Optical properties of colloidal plasmonic titanium nitride nanoparticles are
examined with an eye on their photothermal via transmission electron microscopy
and optical transmittance measurements. Single crystal titanium nitride cubic
nanoparticles with an average size of 50 nm exhibit plasmon resonance in the
biological transparency window. With dimensions optimized for efficient
cellular uptake, the nanoparticles demonstrate a high photothermal conversion
efficiency. A self-passivating native oxide at the surface of the nanoparticles
provides an additional degree of freedom for surface functionalization.Comment: 17 pages, 4 figures, 1 abstract figur
Temperature-dependent optical properties of plasmonic titanium nitride thin films
Due to their exceptional plasmonic properties, noble metals such as gold and
silver have been the materials of choice for the demonstration of various
plasmonic and nanophotonic phenomena. However, noble metals' softness, lack of
tailorability and low melting point along with challenges in thin film
fabrication and device integration have prevented the realization of real-life
plasmonic devices.In the recent years, titanium nitride (TiN) has emerged as a
promising plasmonic material with good metallic and refractory (high
temperature stable) properties. The refractory nature of TiN could enable
practical plasmonic devices operating at elevated temperatures for energy
conversion and harsh-environment industries such as gas and oil. Here we report
on the temperature dependent dielectric functions of TiN thin films of varying
thicknesses in the technologically relevant visible and near-infrared
wavelength range from 330 nm to 2000 nm for temperatures up to 900 0C using
in-situ high temperature ellipsometry. Our findings show that the complex
dielectric function of TiN at elevated temperatures deviates from the optical
parameters at room temperature, indicating degradation in plasmonic properties
both in the real and imaginary parts of the dielectric constant. However, quite
strikingly, the relative changes of the optical properties of TiN are
significantly smaller compared to its noble metal counterparts. Using
simulations, we demonstrate that incorporating the temperature-induced
deviations into the numerical models leads to significant differences in the
optical responses of high temperature nanophotonic systems. These studies hold
the key for accurate modeling of high temperature TiN based optical elements
and nanophotonic systems for energy conversion, harsh-environment sensors and
heat-assisted applications.Comment: 23 pages, 9 figures and 5 table
Fracture Detection And Characterization
The effects of fractures on full waveform acoustic logs are studied on the basis of field
observations, available theoretical models, and a series of ultrasonic laboratory experiments. Results from diffusion models applicable to fine microfractures and finite difference models of isolated fractures are reviewed. Laboratory experiments are carried
out with fine microfractures around the borehole in a Lucite model, and isolated single
fractures in aluminum models. Cases of horizontal and inclined (45°) fractures are
studied as a function of fracture aperture and frequency of Stoneley waves. A vertical
fracture model is also studied. Results indicate that the effect of different fractures are manifested differently on P, S, pseudo-Rayleigh, and Stoneley waves. Micro-fractures
surrounding a borehole attenuate Stoneley waves most strongly. Vertical fractures attenuate Stoneley waves more strongly than other phases in the wave train. Horizontal
and inclined fractures have a greater effect on P and S waves than on Stoneley waves.Massachusetts Institute of Technology. Full Waveform Acoustic Logging Consortiu
Quasi-coherent thermal emitter based on refractory plasmonic materials
The thermal emission of refractory plasmonic metamaterial - a titanium
nitride 1D grating - is studied at high operating temperature (540 {\deg}C). By
choosing a refractory material, we fabricate thermal gratings with high
brightness that are emitting mid-infrared radiation centered around 3 m.
We demonstrate experimentally that the thermal excitation of plasmon-polariton
on the surface of the grating produces a well-collimated beam with a spatial
coherence length of 32{\lambda} (angular divergence of 1.8{\deg}) which is
quasi-monochromatic with a full width at half maximum of 70 nm. These
experimental results show good agreement with a numerical model based on a
two-dimensional full-wave analysis in frequency domain.Comment: 10 pages, 5 figure
Ultrasonic Laboratory Study of Full Waveform Acoustic Logs in Boreholes with Fractures
A set of ultrasonic experiments was carried out to determine the effects of horizontal and vertical fractures on full waveform acoustic logs. Boreholes of 1 cm diameter were drilled in aluminum blocks. Measurements were made with horizontal fractures of 0.05 mm, 1.0 mm, 2.5 mm, and 4.5 mm width and a vertical fracture of 1.0 mm width. The horizontal
fractures of even the smallest thickness significantly attenuate the P, S, and pseudo-Rayleigh waves. The Stoneley waves are the least attenuated, and attenuation increases
with increasing fracture width. The vertical fracture attenuates Stoneley waves most
significantly. Both scattering and fluid flow playa role in attenuation. The results may
qualitatively be extended to inclined open fractures, where we expect strong attenuation
of P and S waves and moderate attenuation of Stoneley waves.Massachusetts Institute of Technology. Full Waveform Acoustic Logging Consortiu
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