Deriving the rate equations characterising product-form models and application to propagating synchronisations

2012 ◽  
Author(s):  
Andrea Marin ◽  
Peter Harrison
Keyword(s):  
Product Form ◽  
Rate Equations

Dielectronic Recombination in the Average-Atom Model

1988 ◽  
Vol 102 ◽  
pp. 215
Author(s):  
R.M. More ◽  
G.B. Zimmerman ◽  
Z. Zinamon
Keyword(s):  
Detailed Balance ◽  
Systematic Errors ◽  
Dielectronic Recombination ◽  
Rate Equations ◽  
Strong Correlations ◽  
Dense Plasmas ◽  
Atom Model ◽  
New Feature ◽  
Average Atom Model ◽  
Attachment Process

Autoionization and dielectronic attachment are usually omitted from rate equations for the non–LTE average–atom model, causing systematic errors in predicted ionization states and electronic populations for atoms in hot dense plasmas produced by laser irradiation of solid targets. We formulate a method by which dielectronic recombination can be included in average–atom calculations without conflict with the principle of detailed balance. The essential new feature in this extended average atom model is a treatment of strong correlations of electron populations induced by the dielectronic attachment process.

On the interpretation of dislocation-loop growth during in-situ high-voltage Electron Microscopy

1990 ◽  
Vol 48 (4) ◽  
pp. 532-533
Author(s):  
E. Holzäpfel ◽  
F. Phillipp ◽  
M. Wilkens
Keyword(s):  
Point Defect ◽  
Rate Equations ◽  
Rate Theory ◽  
Dislocation Loops ◽  
High Voltage Electron Microscopy ◽  
Vacancy Migration ◽  
Voltage Electron ◽  
Reaction Rate Theory ◽  
Defect Reactions

During in-situ radiation damage experiments aiming on the investigation of vacancy-migration properties interstitial-type dislocation loops are used as probes monitoring the development of the point defect concentrations. The temperature dependence of the loop-growth rate v is analyzed in terms of reaction-rate theory yielding information on the vacancy migration enthalpy. The relation between v and the point-defect production rate P provides a critical test of such a treatment since it is sensitive to the defect reactions which are dominant. If mutual recombination of vacancies and interstitials is the dominant reaction, vαP0.5 holds. If, however, annihilation of the defects at unsaturable sinks determines the concentrations, a linear relationship vαP is expected.Detailed studies in pure bcc-metals yielded vαPx with 0.7≾×≾1.0 showing that besides recombination of vacancies and interstitials annihilation at sinks plays an important role in the concentration development which has properly to be incorporated into the rate equations.

A preliminary semantic differential study on users' product form perception

2003 ◽  
Author(s):  
Shi-Jian Luo ◽  
Ming-Xi Tang ◽  
Shang-Shang Zhu ◽  
John Hamilton Frazer ◽  
Shou-Qian Sun ◽  
...  
Keyword(s):  
Semantic Differential ◽  
Product Form ◽  
Form Perception

Exciton dynamics in thick GaN MOVPE epilayers deposited on sapphire.

1997 ◽  
Vol 2 ◽  
Author(s):  
J. Allègre ◽  
P. Lefebvre ◽  
J. Camassel ◽  
B. Beaumont ◽  
Pierre Gibart
Keyword(s):  
Layer Thickness ◽  
Buffer Layers ◽  
Rate Equations ◽  
Time Resolved ◽  
Versus Layer ◽  
Level Model ◽  
Shallow Impurities ◽  
Aln Buffer ◽  
Time Resolved Photoluminescence

Time-resolved photoluminescence spectra have been recorded on three GaN epitaxial layers of thickness 2.5 μm, 7 μm and 16 μm, at various temperatures ranging from 8K to 300K. The layers were deposited by MOVPE on (0001) sapphire substrates with standard AlN buffer layers. To achieve good homogeneities, the growth was in-situ monitored by laser reflectometry. All GaN layers showed sharp excitonic peaks in cw PL and three excitonic contributions were seen by reflectivity. The recombination dynamics of excitons depends strongly upon the layer thickness. For the thinnest layer, exponential decays with τ ~ 35 ps have been measured for both XA and XB free excitons. For the thickest layer, the decay becomes biexponential with τ1 ~ 80 ps and τ2 ~ 250 ps. These values are preserved up to room temperature. By solving coupled rate equations in a four-level model, this evolution is interpreted in terms of the reduction of density of both shallow impurities and deep traps, versus layer thickness, roughly following a L−1 law.

Photocatalytic Discolouration of Solutions of Reactive Dyes in the Presence of H2O2

1995 ◽  
Vol 30 (1) ◽  
pp. 53-60 ◽  
Author(s):  
Deng Nansheng ◽  
Tian Shizhong ◽  
Xia Mei
Keyword(s):  
Photochemical Reaction ◽  
Uv Light ◽  
Reactive Dyes ◽  
Solar Light ◽  
Rate Equations ◽  
Oh Radical ◽  
Test Results ◽  
Dye Molecules ◽  
First Order ◽  
Dye Solutions

Abstract Tests for the photocatalytic degradation of solutions of three reactive dyes, Red M-5B, Procion Blue MX-R and Procion Black H-N, in the presence of H2O2 were carried out. When the solutions of the three reactive dyes were irradiated by UV or solar light, the colour of the solutions disappeared gradually. A statistical analysis of the test results indicated a linear relation between the concentration of dyes and the time of irradiation. The discolouration reaction of the solutions was of the first order. Rate equations for the discolouration reactions of dye solutions were developed. The dark reactions or the dye solutions containing H2O2 were very slow, illustrating that the photochemical reaction played a very important role. It was demonstrated that UV light and solar light (300 to 380 nm) photolyzes the HO and that the resulting OH radical reacts with the dye molecules and destroys the chromophore.

Ceramic-ware along the Ancient Silk Trade Route—A Short Study of Cross-Cultural Influences on Product Form

2016 ◽  
Vol 4 (2) ◽  
pp. 84-97
Author(s):  
Ravi Mokashi Punekar ◽  
◽  
Shiva Ji ◽  
Keyword(s):  
Material Culture ◽  
Cultural Influences ◽  
Cross Cultural ◽  
Product Form ◽  
Ceramic Ware ◽  
Ancient Times ◽  
Silk Route ◽  
Trade Route ◽  
Multiple Domains ◽  
Trading Routes

The exchange of goods and materials by way of trading and exchanges were common in ancient times between India and China via silk route and other trading routes. The movement of people from one place to another brought exchange of not only materials but also techniques and processes and helped to establish their own manufacturing facilities and craftsmanship. This has resulted into a cross-cultural influence over the craft forms as reflected in many resemblances of material culture, annotations and apologies seen in various forms and shapes in multiple domains such as ceramic pottery, glazed pottery, metalware, ship buildings, printing, silk and other fabrics, patterns and motifs etc. Observations of ancient remains from Belitung and artifacts from Indian cities along secondary and tertiary Silk routes, show significant influence in the similarities in techniques, materials, surface treatments, kiln processes, colors, motifs , etc. This paper examines a cross-cultural resemblance of product form factor between Changsha pottery and pots to ceramic ware from eastern parts and metalware from western regions of India like Gujarat and Rajasthan. The spread of Buddhism from India to China and other eastern and south eastern countries during this period must also form a strong reason for this cultural exchange.

Nonisochoric Reactor with Constant Feed Rate of One Component

1993 ◽  
Vol 58 (7) ◽  
pp. 1476-1484
Author(s):  
Václav Dušek ◽  
František Skopal
Keyword(s):  
Sulfuric Acid ◽  
Acid Medium ◽  
Feed Rate ◽  
Redox System ◽  
Chemical Reactor ◽  
Constant Volume ◽  
Rate Equations ◽  
Sulfuric Acid Medium ◽  
Constant Feed Rate

For a chemical reactor with constant volume feed rate equations have been derived which describe the time dependences of concentration of the reaction components, and their approximation has been suggested. The applicability of the approximation has been verified on a model redox system Ce(IV)/V(IV) in sulfuric acid medium.

A polycentric growth model of gallium arsenide epitaxial layers from the gas phase with simultaneous diffusion, adsorption and chemical reaction

1988 ◽  
Vol 53 (12) ◽  
pp. 2995-3013
Author(s):  
Emerich Erdös ◽  
Jindřich Leitner ◽  
Petr Voňka ◽  
Josef Stejskal ◽  
Přemysl Klíma
Keyword(s):  
Growth Rate ◽  
Gallium Arsenide ◽  
Epitaxial Growth ◽  
Gas Phase ◽  
Surface Reaction ◽  
Quantitative Description ◽  
The Other ◽  
Rate Equations ◽  
Impact Interaction ◽  
Partial Pressures

For a quantitative description of the epitaxial growth rate of gallium arsenide, two models are proposed including two rate controlling steps, namely the diffusion of components in the gas phase and the surface reaction. In the models considered, the surface reaction involves a reaction triple - or quadruple centre. In both models three mechanisms are considered which differ one from the other by different adsorption - and impact interaction of reacting particles. In every of the six cases, the pertinent rate equations were derived, and the models have been confronted with the experimentally found dependences of the growth rate on partial pressures of components in the feed. The results are discussed with regard to the plausibility of individual mechanisms and of both models, and also with respect to their applicability and the direction of further investigations.

State-dependent signalling in queueing networks

1994 ◽  
Vol 26 (02) ◽  
pp. 436-455 ◽  
Author(s):  
W. Henderson ◽  
B. S. Northcote ◽  
P. G. Taylor
Keyword(s):  
Queueing Networks ◽  
State Dependence ◽  
Product Form ◽  
Batch Size ◽  
Single Server ◽  
Negative Customers ◽  
Affect Control ◽  
State Dependent ◽  
Special Cases ◽  
Equilibrium Distributions

It has recently been shown that networks of queues with state-dependent movement of negative customers, and with state-independent triggering of customer movement have product-form equilibrium distributions. Triggers and negative customers are entities which, when arriving to a queue, force a single customer to be routed through the network or leave the network respectively. They are ‘signals' which affect/control network behaviour. The provision of state-dependent intensities introduces queues other than single-server queues into the network. This paper considers networks with state-dependent intensities in which signals can be either a trigger or a batch of negative customers (the batch size being determined by an arbitrary probability distribution). It is shown that such networks still have a product-form equilibrium distribution. Natural methods for state space truncation and for the inclusion of multiple customer types in the network can be viewed as special cases of this state dependence. A further generalisation allows for the possibility of signals building up at nodes.

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