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R134a flow patterns in small diameter tubes
R134a vapour-liquid two-phase flow patterns were studied in vertical small diameter tubes. The observed flow patterns include bubbly, dispersed bubble, slug, churn, annular and mist flow. Six integrated flow pattern maps, derived for two internal diameters (2.01 and 4.26 mm) and three different pressures (6.0, 10.0, 14.0 bar), are presented. Some transition boundaries, such as slug-churn and churn-annular, were found to be very sensitive to diameter and pressure. On the contrary, the boundaries of dispersed bubble-churn and bubbly-slug are less affected. The transition boundaries are compared with the existing models for normal size tubes showing significant differences
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The effect of tube diameter on vertical two-phase flow regimes in small tubes
Flow boiling flow patterns in four circular tubes with internal diameters of 1.10, 2.01, 2.88 and 4.26 mm were investigated in the present project. The experiments were conducted in vertical upward two-phase flow using R134a as the working fluid. The observed flow patterns include dispersed bubble, bubbly, confined bubble, slug, churn, annular and mist flow. The flow characteristics in the 2.88 and 4.26 mm tubes are similar to those typically described in normal size tubes. The smaller diameter tubes, 1.10 and 2.01 mm, exhibit strong "small tube characteristics" as described in earlier studies. The sketched flow maps show that the transition boundaries of slug-churn and churn-annular depend strongly on diameter. On the contrary, the dispersed bubble to churn and bubbly to slug boundaries are less affected. The transition boundaries are compared with existing models for normal size tubes showing poor agreement
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Vertical upward flow patterns in small diameter tubes
Two-phase flow patterns were studied in vertical small diameter tubes using R134a as the working fluid. The observed flow patterns include bubbly, dispersed bubble, confined bubble, slug, churn, annular and mist flow. Twelve flow pattern maps, derived from four internal diameters (1.10, 2.01, 2.88 and 4.26 mm) and three different pressures (6, 10, 14 bar), are presented. The flow patterns exhibit strong “small tube characteristics” described in earlier studies when the tube diameter is 2 mm or less. Slug-churn and churn-annular boundaries depend on diameter and pressure. Dispersed bubble-churn and bubbly-slug are less affected. The transition boundaries are compared with existing models for normal size tubes showing poor agreement. Various coordinate systems were considered for the flow maps. The results show that the Lockhard-Martinelli Parameter and mass flow flux can account for the effect of fluid pressure on flow patterns
Optimizing culture medium for debittering constitutive enzyme naringinase production by Aspergillus oryzae JMU316
The objective of this study was to investigate nutrient requirements for extracellular constitutive naringinase production by Aspergillus oryzae JMU316. The one-factor-at-a-time method was used to determine the impact of different carbon and nitrogen sources on naringinase production. Naringin exhibited the highest naringinase activity compared to all other carbon sources and pomelo pericarp powder produced comparable naringinase activity. Pomelo pericarp powder was selected as carbon source because it is a waste of fruit process, which means that it is a cheap resource and has additional environmental benefits. Peptone proved to be the most suitable nitrogen source for naringinase production. Subsequently, the orthogonal matrix method was used to further optimize the concentration of pomelo pericarp powder, peptone, and minerals. The optimal concentration of the components were15 g pomelo pericarp powder, 12 g peptone, 0.2 g CaCl2, 0.4 g NaCl, 2 g MgSO4·7H2O and 1 g K2HPO4 in 1 L distilled water for producing 408.28 IU/mL naringinase activity. The effects of medium components on naringinase were in the order of pomelo pericarp powder, K2HPO4, NaCl, peptone, CaCl2, MgSO4·7H2O. This two-step optimization strategy used in this study can be widely applied to other microbial fermentation processes.Key words: Pomelo pericarp powder, orthogonal matrix method, naringinase, culture medium optimization, Aspergillus oryzae JMU316
Scalable Similarity Search for Molecular Descriptors
Similarity search over chemical compound databases is a fundamental task in
the discovery and design of novel drug-like molecules. Such databases often
encode molecules as non-negative integer vectors, called molecular descriptors,
which represent rich information on various molecular properties. While there
exist efficient indexing structures for searching databases of binary vectors,
solutions for more general integer vectors are in their infancy. In this paper
we present a time- and space- efficient index for the problem that we call the
succinct intervals-splitting tree algorithm for molecular descriptors (SITAd).
Our approach extends efficient methods for binary-vector databases, and uses
ideas from succinct data structures. Our experiments, on a large database of
over 40 million compounds, show SITAd significantly outperforms alternative
approaches in practice.Comment: To be appeared in the Proceedings of SISAP'1
Cellular modelling of Alström syndrome in human primary dermal fibroblasts and derived cells
RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are
Nano-FTIR Spectroscopy of Intersubband Polaritons in Single Nanoantenna
We demonstrate observation of infrared (IR) intersubband (ISB) polaritons in an isolated subwavelength size nanoantenna using near-field Fourier-transform infrared (FTIR) spectroscopy of the evanescent fields on the nanoantenna surface. The near-field approach enables detection of the distinctive polariton splitting of the nanoantenna resonance in the amplitude and phase spectra, as well as mapping of the ISB polariton dispersion. The nano-FTIR spectroscopy approach opens doors for investigations of light-matter interaction in the single subwavelength nanoantenna regime
Cognitively-inspired Agent-based Service Composition for Mobile & Pervasive Computing
Automatic service composition in mobile and pervasive computing faces many
challenges due to the complex and highly dynamic nature of the environment.
Common approaches consider service composition as a decision problem whose
solution is usually addressed from optimization perspectives which are not
feasible in practice due to the intractability of the problem, limited
computational resources of smart devices, service host's mobility, and time
constraints to tailor composition plans. Thus, our main contribution is the
development of a cognitively-inspired agent-based service composition model
focused on bounded rationality rather than optimality, which allows the system
to compensate for limited resources by selectively filtering out continuous
streams of data. Our approach exhibits features such as distributedness,
modularity, emergent global functionality, and robustness, which endow it with
capabilities to perform decentralized service composition by orchestrating
manifold service providers and conflicting goals from multiple users. The
evaluation of our approach shows promising results when compared against
state-of-the-art service composition models.Comment: This paper will appear on AIMS'19 (International Conference on
Artificial Intelligence and Mobile Services) on June 2
Collider Phenomenology with Split-UED
We investigate the collider implications of Split Universal Extra Dimensions.
The non-vanishing fermion mass in the bulk, which is consistent with the
KK-parity, largely modifies the phenomenology of Minimal Universal Exta
Dimensions. We scrutinize the behavior of couplings and study the discovery
reach of the Tevatron and the LHC for level-2 Kaluza-Klein modes in the
dilepton channel, which would indicates the presence of the extra dimensions.
Observation of large event rates for dilepton resonances can result from a
nontrivial fermion mass profile along the extra dimensions, which, in turn, may
corroborate extra dimensional explanation for the observation of the positron
excess in cosmic rays.Comment: 23 pages, 15 figure
Leucine‐Rich Amelogenin Peptide: A Candidate Signaling Molecule During Cementogenesis
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141564/1/jper1126.pd
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