scholarly journals First observation of radiolytic bubble formation in unstirred nano-powder sludges and a consistent model thereof

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mel O’Leary ◽  
Aliaksandr Baidak ◽  
Martyn Barnes ◽  
Thomas Donoclift ◽  
Christopher Emerson ◽  
...  
Keyword(s):  
Molecular Hydrogen ◽  
Consumption Rate ◽  
Bubble Formation ◽  
Bulk Water ◽  
Gas Production ◽  
Ionization Mechanism ◽  
Dissolved Gas ◽  
Nano Powder ◽  
Consistent Model

AbstractExperiments involving the irradiation of water contained within magnesium hydroxide and alumina nanoparticle sludges were conducted and culminated in observations of an increased yield of molecular hydrogen when compared to the yield from the irradiation of bulk water. We show that there is a relationship linking this increased yield to the direct nanoscale ionization mechanism in the nanoparticles, indicating that electron emission from the nanoparticles drives new radiative pathways in the water. Because the chemical changes in these sludges are introduced by irradiation only, we have a genuinely unstirred system. This feature allows us to determine the diffusivity of the dissolved gas. Using the measured gas production rate, we have developed a method for modelling when hydrogen bubble formation will occur within the nanoparticle sludges. This model facilitates the determination of a consistent radiolytic consumption rate coinciding with the observations of bubble formation. Thus, we demonstrate a nanoscale radiation effect directly influencing the formation of molecular hydrogen.

Effect of dissolved gas on bubble formation and boiling heat transfer in forced flow boiling

2020 ◽  
Vol 2020 (0) ◽  
pp. 16B01
Author(s):  
Hiroaki NARAZAKI ◽  
Satoshi MATSUMOTO ◽  
Yutaka ABE ◽  
Akiko KANEKO
Keyword(s):  
Heat Transfer ◽  
Boiling Heat Transfer ◽  
Flow Boiling ◽  
Bubble Formation ◽  
Forced Flow ◽  
Dissolved Gas

Corporations

2020 ◽  
pp. 151-182
Author(s):  
Danny M. Adkison ◽  
Lisa McNair Palmer
Keyword(s):  
Natural Gas ◽  
Gas Production ◽  
Economic Life ◽  
Regulatory Control ◽  
Natural Gas Production ◽  
Motor Carriers ◽  
Cotton Gins ◽  
Oil And Natural Gas ◽  
Water Companies

This chapter examines Article IX of the Oklahoma constitution, which concerns the powers, limits, and regulation of corporations. The prodigious length of the article reflects the importance of corporations in the economic life of Oklahoma, and the determination of the framers to bring them under regulatory control, to the point of micromanagement. Concern about discriminatory rates charged by railroads and pipelines was foremost, but the authority conferred by Article IX is broad enough to allow the legislature to regulate a variety of other enterprises as well, including electric, gas, and water companies; oil and natural gas production; and conservation, cotton gins, motor carriers, telephone and telegraph lines; and even ice plants. The framers borrowed freely from the constitutions and statutes of other states—especially the Virginia constitution, the Texas constitution, and the Texas Railway Act—as models for Article IX. Whole sections were often copied verbatim. Moreover, often competing strains of waning Populism and rising Progressivism of the early 1900s pervade this article.

The comparison between nylon bag and gas production method, use of regression equations in determination of feedstuffs nutritive value

2007 ◽  
Vol 2007 ◽  
pp. 211-211
Author(s):  
Ali Mahdavi ◽  
Ali Nikkhah ◽  
Fatemeh Alemi
Keyword(s):  
Nutritive Value ◽  
Production Method ◽  
Gas Production ◽  
Chemical Components ◽  
Regression Equations ◽  
Evaluation Systems ◽  
Ruminal Degradation ◽  
Production Characteristics

The in situ technique forms the basis of many feed evaluation systems for ruminants. Although this method is widely used, the NBT is very laborious, time-consuming, and incubations and analyses of the feed residues often last several weeks. Therefore, several other techniques have been investigated to measure and predict ruminal degradation of various chemical components of feedstuffs. The aim of this study is to investigate the possibilities of estimating in situ degradation characteristics of DM, CP, ADF and NDF in several feedstuffs by gas production characteristics and chemical composition.

scholarly journals Transformer Fault Diagnosis Based on BP-Adaboost and PNN Series Connection

2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
Chun Yan ◽  
Meixuan Li ◽  
Wei Liu
Keyword(s):  
Neural Network ◽  
Bp Neural Network ◽  
Rapid Determination ◽  
Oil Analysis ◽  
Dissolved Gas ◽  
Adaboost Algorithm ◽  
Diagnosis Model ◽  
The Stability ◽  
Transformer Fault

Dissolved gas-in-oil analysis (DGA) is a powerful method to diagnose and detect transformer faults. It is of profound significance for the accurate and rapid determination of the fault of the transformer and the stability of the power. In different transformer faults, the concentration of dissolved gases in oil is also inconsistent. Commonly used gases include hydrogen (H2), methane (CH4), acetylene (C2H2), ethane (C2H6), and ethylene (C2H4). This paper first combines BP neural network with improved Adaboost algorithm, then combines PNN neural network to form a series diagnosis model for transformer fault, and finally combines dissolved gas-in-oil analysis to diagnose transformer fault. The experimental results show that the accuracy of the series diagnosis model proposed in this paper is greatly improved compared with BP neural network, GA-BP neural network, PNN neural network, and BP-Adaboost.

Controlling sulfide generation in force mains by air injection

1998 ◽  
Vol 37 (1) ◽  
pp. 87-95 ◽  
Author(s):  
Takatoshi Ochi ◽  
Mitsuo Kitagawa ◽  
Syuji Tanaka
Keyword(s):  
Oxygen Consumption ◽  
Gaseous Phase ◽  
Oxygen Consumption Rate ◽  
Consumption Rate ◽  
Bulk Water ◽  
Air Injection ◽  
Oxygen Balance ◽  
Experimental Facility ◽  
Minimum Concentration ◽  
Pipe Outlet

Air injection into force mains has been used to control sulfide generation. However, the design criteria have not been clearly established. In this study, the minimum concentration of dissolved oxygen (DO) required to prevent sulfide generation, and the oxygen balance in the force mains were investigated using an experimental facility. Air injection completely eliminated sulfide presence at the pipe outlet when DO at the pipe end was 0.2 mg/l or higher. Reaeration from gaseous phase to wastewater was affected by sewage flow velocity and oxygen concentration in the gaseous phase. Oxygen consumption rate in bulk water (Rr) ranged widely from 3 to 18 mg/l.h. Oxygen consumption rate in biofilm (Re) was measured using a rotating reactor. Re seemed to increase in proportion to the square root of DO.

Determination of oxygen profiles and diffusivity in encapsulated biomass k-carrageenan gel beads

1997 ◽  
Vol 36 (1) ◽  
pp. 271-277 ◽  
Author(s):  
Qin Zhou ◽  
Paul L. Bishop
Keyword(s):  
Gas Flow ◽  
Consumption Rate ◽  
Thin Liquid Film ◽  
Reaction Diffusion ◽  
Gel Beads ◽  
Reaction Diffusion Model ◽  
Volatile Organic ◽  
Oxygen Profiles ◽  
Gel Bead

Biofiltration is a popular method for removing volatile organic compounds (VOCs). One promising medium for biofilters is biomass encapsulated gel beads. Like any other biodegradation system, oxygen concentration is an important factor affecting microbial activities in gel beads and thus the VOC removal efficiency. This paper summarizes the studies on oxygen distribution and diffusivity in k-carrageenan gel beads using oxygen microelectrodes to measure oxygen profiles. By using a reaction-diffusion model and the concentration measurements obtained, a homogeneous diffusivity constant and an oxygen consumption rate constant in k-carrageenan gel beads were estimated. The estimated oxygen diffusivity in the gel bead is 46.3% of the value in water when the bead is immersed in water and 53.9% that of water when the bead is in air with a thin liquid film surrounding it. To provide more information for the design and operation of biofilters using biomass-loaded gel beads, we also investigated and report on effects of biomass immobilization time, TCE influent concentration and TCE gas flow rate on oxygen concentrations in the gel bead.

scholarly journals Highly Excited Molecular Hydrogen in Orion

1989 ◽  
Vol 120 ◽  
pp. 323-326
Author(s):  
Hans H. Hippelein ◽  
Guido Münch
Keyword(s):  
Molecular Hydrogen ◽  
Rotational Temperature ◽  
Energy State ◽  
Low Energy ◽  
Line Of Sight ◽  
Temperature Measuring ◽  
Molecule Formation ◽  
J 13 ◽  
Excitation Mechanisms

Observations of H2 lines in the IR have been mostly restricted to those with upper levels of low energy, which can be excited either collisionally in shocks or radiatively by UV starlight. In order to discriminate between the two excitation mechanisms we have measured in 11 μm range lines of the v=2-0 band arising from high rotational levels J≤;13. Their intensities, together with those of the IR lines, allow an estimate of the line of sight effective extinction and a determination of the rotational temperature measuring their joint degree of excitation. The latter parameter provides information about the energy state of the molecules at their formation and ejection from grain surfaces and thus constrains the hypothetical models for H2 molecule formation.

Nonlinear Dynamics of a Spar Platform

2012 ◽  
Author(s):  
Elvidio Gavassoni ◽  
Paulo Batista Gonçalves ◽  
Deane M. Roehl
Keyword(s):  
Asymptotic Methods ◽  
Weather Conditions ◽  
Gas Production ◽  
Spar Platform ◽  
Highly Nonlinear ◽  
Oil And Natural Gas ◽  
The Stability ◽  
Floating Platforms ◽  
And Storage

Spar floating platforms have been largely used for deep water drilling, oil and natural gas production and storage of these fluids. In extreme weather conditions such structures may exhibit a highly nonlinear dynamic behavior. In this paper a 2-DOF model is used to study the heave and pitch coupled response in free and forced vibration. Special attention is given to the determination of the nonlinear vibration modes (NNMs). Non-similar and similar NNMs are obtained analytically by direct application of asymptotic methods and the results show important NNM features such as instability and multiplicity of modes. The NNMs are used to generate reduced order models that consist of 1-DOF nonlinear oscillators. It facilitates the parametric analysis and the derivation of important features of the system such as the frequency-amplitude relation associated to each nonlinear mode and resonance curves. The stability is analyzed by the Floquet theory. Bifurcation diagrams and Mathieu charts are used to identify the unstable regions in the force parameter space. The analytical results show good agreement with the numerical solution obtained by direct integration of the equation of motion.

Sign in / Sign up

Export Citation Format

Share Document