Heat Transfer from a Cylinder in Cross-Flow of Single and Multiphase Flows

In this paper, the average heat transfer characteristics for a cross flow cylinder of 16 mm diameter in a vertical pipe has been studied for single-phase flow (water/oil) and multicomponent (non-boiling) flow (water-air, water-oil, oil-air and water-oil-air). The cylinder is uniformly heated by electrical heater placed at the centre of the element. The results show that the values of average heat transfer coefficients for water are around four times the values for oil flow. Introducing air as a second phase with water has very little effect on heat transfer rate, while the heat transfer increased by 70% in case of oil. For water–oil flow, the heat transfer coefficient values are reflecting the percentage of water up to 50%, but increasing the water more than 50% leads to a sharp increase in the heat transfer coefficients to become close to the values of pure water. The enhancement of heat transfer by mixing two phases may be attributed to the changes in flow structure near to cylinder surface which lead to thinner boundary layer and higher turbulence. For three-phase flow, the heat transfer coefficients for all cases fall within the limit of single-phase flow of water and oil and are very close to pure water values. The net effect of the turbulence augmentation due to the introduction of air and the attenuation due to the introduction of oil leads to a thinner boundary layer of oil over the cylinder surface covered by a mixture of water and air bubbles

Analysis of main trends in food nanotechnology innovation: a technology surveillance-based

en el estudio se analizan las principales tendencias en producción científica y tecnológica en el área de nanotecnología de alimentos. El propósito se centró en conocer su evolución y así poder identificar oportunidades potenciales de innovación, con base en sus principales usos y aplicación en la industria alimenticia. Se utilizó la Vigilancia Tecnológica, indicadores cienciométricos, así como la teoría de redes y grafos para la visualización y análisis del comportamiento de las principales áreas de investigación y desarrollo tecnológico, con base en el tema de estudio. Se identificaron ocho potenciales oportunidades de innovación en el área: nanopartículas, nanomateriales, nanocompuestos, nanoemulsión, nanoencapsulación, microencapsulación, nanorecubrimientos y nanosensores; las cuales están influyendo notablemente en el desarrollo de la industria de alimentos y se han convertido en elementos claves de investigación y desarrollo tecnológico a nivel mundial. El uso y aplicación de la nanotecnología en la industria de alimentos han aumentado rápidamente en las últimas décadas y su constante evolución ha tenido una gran contribución en el desarrollo de la industria.  This study analyzes the main trends in scientific and technological production in the field of food nanotechnology. The purpose is to describe their evolution and thus identify potential opportunities for innovation based on their main uses and applications in the food industry. Technology Surveillance, scientometric indicators, and graph and network theory were used to visualize and analyze the behavior of the main research fields and technological development of the subject under study. We identified 8 potential innovation opportunities in the area: nanoparticles, nanomaterials, nanocomposites, nanoemulsions, nanoencapsulation, microencapsulation, nanorecovering, and nanosensors. All of them are significantly influencing the development of the food industry and have become key elements of research and technological progress worldwide. The uses and applications of nanotechnology in the food industry have rapidly expanded in recent decades, and their constant evolution has made a great contribution to the development of this sector

Effects of Lateral Diffusion on the Dynamics of Desorption

The adsorbate dynamics during simultaneous action of desorption and lateral adsorbate diffusion is studied in a simple lattice-gas model by kinetic Monte Carlo simulations. It is found that the action of the coverage-conserving diffusion process during the course of the desorption has two distinct, competing effects: a general acceleration of the desorption process, and a coarsening of the adsorbate configuration through Ostwald ripening. The balance between these two effects is governed by the structure of the adsorbate layer at the beginning of the desorption process

Voltage-Dependent Anion Channel 2 of Arabidopsis thaliana (AtVDAC2) Is Involved in ABA-Mediated Early Seedling Development

The voltage-dependent anion channel (VDAC) is the major transport protein in the outer membrane of mitochondria and plays crucial roles in energy metabolism, apoptosis, and metabolites transport. In plants, the expression of VDACs can be affected by different stresses, including drought, salinity and pathogen defense. In this study, we investigated the expression pattern of AtVDAC2 in A. thaliana and found ABA suppressed the accumulation of AtVDAC2 transcripts. Further, phenotype analysis of this VDAC deregulated-expression transgenic Arabidopsis plants indicated that AtVDAC2 anti-sense line showed an ABA-insensitivity phenotype during the early seedling development under ABA treatment. The results suggested that AtVDAC2 might be involved in ABA signaling in A. thaliana

3D reactive inkjet printing of polydimethylsiloxane

Material jetting is a process whereby liquid material can be deposited onto a substrate to solidify. Through a process of progressive additional layers, this deposition can then be used to produce 3D structures. However, the current material jetting catalogue is limited owing to the constraints on the viscosity of inks that can be deposited. Most inks currently being used are either solvent or photocuring based, with the latter becoming increasingly popular due to increased throughput. Full Reactive Inkjet Printing (FRIJP) is an alternative processing method currently being investigated as a route to widen the material catalogue. FRIJP is the combination, on the substrate, of two reactive components which then react together in contact on the substrate. In this work a two-part polydimethylsiloxane (PDMS) ink has been developed, printed individually, and cured. The successful printing of PDMS has been used to fabricate complex 3D geometry for the first time using FRIJP. Through the use of a prepared substrate feature resolutions up to 48 ± 2 μm (X, Y) were possible. Curing analysis has been conducted. It was found that not only does the reaction occur to a similar degree to conventional processes, but that there is no variation in the cured sample when printed at elevated substrate temperatures

Bulk properties of the system formed in Au+Au collisions at sNN =14.5 GeV at the BNL STAR detector

We report systematic measurements of bulk properties of the system created in Au+Au collisions at sNN=14.5 GeV recorded by the STAR detector at the Relativistic Heavy Ion Collider (RHIC). The transverse momentum spectra of π±, K±, and p(p) are studied at midrapidity (|y|<0.1) for nine centrality intervals. The centrality, transverse momentum (pT), and pseudorapidity (η) dependence of inclusive charged particle elliptic flow (v2), and rapidity-odd charged particles directed flow (v1) results near midrapidity are also presented. These measurements are compared with the published results from Au+Au collisions at other energies, and from Pb+Pb collisions at sNN=2.76 TeV. The results at sNN=14.5 GeV show similar behavior as established at other energies and fit well in the energy dependence trend. These results are important as the 14.5-GeV energy fills the gap in μB, which is of the order of 100 MeV, between sNN=11.5 and 19.6 GeV. Comparisons of the data with UrQMD and AMPT models show poor agreement in general

Measurements of the transverse-momentum-dependent cross sections of J /ψ production at mid-rapidity in proton+proton collisions at s =510 and 500 GeV with the STAR detector

We present measurements of the differential cross sections of inclusive J/ψ meson production as a function of transverse momentum (pTJ/ψ) using the μ+μ- and e+e- decay channels in proton+proton collisions at center-of-mass energies of 510 and 500 GeV, respectively, recorded by the STAR detector at the Relativistic Heavy Ion Collider. The measurement from the μ+μ- channel is for

Charge-dependent pair correlations relative to a third particle in p + Au and d + Au collisions at RHIC

Quark interactions with topological gluon configurations can induce chirality imbalance and local parity violation in quantum chromodynamics. This can lead to electric charge separation along the strong magnetic field in relativistic heavy-ion collisions – the chiral magnetic effect (CME). We report measurements by the STAR collaboration of a CME-sensitive observable in p+Au and d+Au collisions at 200 GeV, where the CME is not expected, using charge-dependent pair correlations relative to a third particle. We observe strong charge-dependent correlations similar to those measured in heavy-ion collisions. This bears important implications for the interpretation of the heavy-ion data