Does Co-Location Accelerate Knowledge Outflows from FDI? The Role of MMC Subsidiaries' Technology Sourcing Strategies

Despite the strategic importance of the knowledge outflows from FDI for local firms’ competitiveness, no study has focused on the speed at which this phenomenon takes place. However, this issue is crucial since the speed at which firms absorb external knowledge influences the time they need to carry out subsequent innovations, their ability to adapt to external changes and enter new markets, thus ultimately affecting their chances to achieve a competitive advantage. This paper tries to fill this gap, by investigating the temporal patterns of knowledge outflows between foreign subsidiaries and firms located in host-regions. Combining International Business literature with insights on Innovation Strategy, we provide evidence on the timing of this phenomenon, and discuss the role played by multinational firms’ technology sourcing strategies

Nitrogen fertilisation management in precision agriculture: a preliminary application example on maize

The adoption of precision agriculture techniques for N management has the potential for improving agronomic, economic and environmental efficiency in the use of such input. The present work was aimed at testing a simplified N balance method for the prescription of N fertilisation in uniform management zones defined from information on measured soil properties on grain maize in central Italy. The results of this preliminary experience show that the application of the N balance prescription map did not bring to significant differences, from a uniform N fertilisation, in terms of grain yield, economic return above N cost and nitrate content in the soil profile at the end of the growing season. However, the adoption of the prescribed N fertilisation strategy for the whole field would have caused a limited saving in the amount of fertiliser employed, quantified at about 10 kg N ha–1

Enhancing thermoelectric performance of Bi2Te3-based nanostructures through rational structure design

Nanostructuring has been successfully employed to enhance the thermoelectric performance of Bi2Te3 due to its obtained low thermal conductivity. In order to further reduce the thermal conductivity, we designed a hierarchical nanostructure assembled with well-aligned Bi2Te3 nanoplates using Te nanotubes as templates by a facile microwave-assisted solvothermal synthesis. From the comparisons of their thermoelectric performance and theoretical calculations with simple Bi2Te3 nanostructures, we found that Te/Bi2Te3 hierarchical nanostructures exhibit a higher figure-of-merit due to the optimized reduced Fermi level and enhanced phonon scattering, as well as the suppressed bipolar conduction. This study provides an effective approach to enhance the thermoelectric performance of Bi2Te3-based nanostructures by rationally designing the nanostructures

Thermal stability and oxidation of layer-structured rhombohedral In3Se4 nanostructures

The thermal stability and oxidation of layer-structured rhombohedral In3Se4 nanostructures have been investigated. In-situ synchrotron X-ray diffraction in a sealed system reveals that In3Se4 has good thermal stability up to 900 degrees C. In contrast, In3Se4 has lower thermal stability up to 550 or 200 degrees C when heated in an atmosphere flushed with Ar or in air, respectively. The degradation mechanism was determined to be the oxidation of In3Se4 by O-2 in the heating environment. This research demonstrates how thermal processing conditions can influence the thermal stability of In3Se4, suggesting that appropriate heating environment for preserving its structural integrity is required. (C) 2013 AIP Publishing LLC

Magnetotransport properties of Cd3As2 nanostructures

Three-dimensional (3D) topological Dirac semimetal is a new kind of material that has a linear energy dispersion in 3D momentum space and can be viewed as an analog of graphene. Extensive efforts have been devoted to the understanding of bulk materials, but yet it remains a challenge to explore the intriguing physics in low-dimensional Dirac semimetals. Here, we report on the synthesis of Cd3As2 nanowires and nanobelts and a systematic investigation of their magnetotransport properties. Temperature-dependent ambipolar behavior is evidently demonstrated, suggesting the presence of finite-size of bandgap in nanowires. Cd3As2 nanobelts, however, exhibit metallic characteristics with a high carrier mobility exceeding 32,000 cm2V-1s-1 and pronounced anomalous double-period Shubnikov-de Haas (SdH) oscillations. Unlike the bulk counterpart, the Cd3As2 nanobelts reveal the possibility of unusual change of the Fermi sphere owing to the suppression of the dimensionality. More importantly, their SdH oscillations can be effectively tuned by the gate voltage. The successful synthesis of Cd3As2 nanostructures and their rich physics open up exciting nanoelectronic applications of 3D Dirac semimetals.Comment: 18 pages, 5 figure

Au impact on GaAs epitaxial growth on GaAs (111)B substrates in molecular beam epitaxy

GaAs growth behaviour under the presence of Au nanoparticles on GaAs {111}(B) substrate is investigated using electron microscopy. It has been found that, during annealing, enhanced Ga surface diffusion towards Au nanoparticles leads to the GaAs epitaxial growth into {113}(B) faceted triangular pyramids under Au nanoparticles, governed by the thermodynamic growth, while during conventional GaAs growth, growth kinetics dominates, resulting in the flatted triangular pyramids at high temperature and the epitaxial nanowires growth at relatively low temperature. This study provides an insight of Au nanoparticle impact on GaAs growth, which is critical for understanding the formation mechanisms of semiconductor nanowires. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4792053

Boosting the thermoelectric performance of p-type heavily Cu-doped polycrystalline SnSe via inducing intensive crystal imperfections and defect phonon scattering

In this study, we, for the first time, report a high Cu solubility of 11.8% in single crystal SnSe microbelts synthesized via a facile solvothermal route. The pellets sintered from these heavily Cu-doped microbelts show a high power factor of 5.57 μW cm−1 K−2 and low thermal conductivity of 0.32 W m−1 K−1 at 823 K, contributing to a high peak ZT of ∼1.41. Through a combination of detailed structural and chemical characterizations, we found that with increasing the Cu doping level, the morphology of the synthesized Sn1−xCuxSe (x is from 0 to 0.118) transfers from rectangular microplate to microbelt. The high electrical transport performance comes from the obtained Cu+ doped state, and the intensive crystal imperfections such as dislocations, lattice distortions, and strains, play key roles in keeping low thermal conductivity. This study fills in the gaps of the existing knowledge concerning the doping mechanisms of Cu in SnSe systems, and provides a new strategy to achieve high thermoelectric performance in SnSe-based thermoelectric materials