Enhancement of the Catalytic Performances in the Case of a Consecutive-Parallel Reaction Scheme

2010 ◽  
Vol 8 (1) ◽  
Author(s):  
Yacine Benguerba ◽  
Brahim Djellouli
Keyword(s):  
Considerable Increase ◽  
Reaction Scheme ◽  
Element Distribution ◽  
Parallel Reaction ◽  
Bulk Fluid ◽  
Optimal Position ◽  
Dirac Function ◽  
Specific Distance ◽  
Catalytic Performances

The determination of the optimal distribution of the catalytic activity profile, which maximizes the catalytic effectiveness and the selectivity, in created unsteady state conditions, is analyzed and treated numerically for the case of a consecutive-parallel reaction scheme. The optimal active element distribution is always a Dirac-? function, i.e., all the catalyst is deposited at a specific distance from the center of the catalytic pellet. The main result is that the location of this optimal position varies with time and that the modulation, of the temperature and the reactants concentrations of the external bulk fluid, leads to a considerable increase of the catalytic effectiveness. On the other hand the selectivity was found to be not affected by the modulation except for higher values of ?2 (?2>0.3).

The Determination of the Three-Point Support Design of Machine Tool Based on iSIGHT

2014 ◽  
Vol 607 ◽  
pp. 342-345
Author(s):  
Sheng Hui Zhao ◽  
Xiao Chuang Zhu ◽  
Da Wei Zhang
Keyword(s):  
Machine Tool ◽  
High Precision ◽  
Multidisciplinary Optimization ◽  
Joint Surface ◽  
Objective Functions ◽  
Multi Objective Optimization ◽  
Support Design ◽  
Optimal Position ◽  
Point Support

In order to meet the requirements of high-precision machine tool, it has been an important factor to select an appropriate way to support the bed. By building a multidisciplinary optimization (MDO) process based on iSIGHT, this article select the deformation difference of the guides and the deformation difference of the joint surface between column and bed of the machine tool as the objective functions, and then conduct a multi-objective optimization (MOO) of the positional parameters of the three-point support. Eventually the optimization result is given and the optimal position of the three-point support is determined.

Determination of Reaction Scheme and Kinetic Parameters

1986 ◽  
pp. 293-339
Author(s):  
Satoru Kuhara ◽  
Kiyokazu Nemoto ◽  
Yukihiro Eguchi ◽  
Naoto Sakamoto
Keyword(s):  
Kinetic Parameters ◽  
Reaction Scheme

scholarly journals Assessing the effect of wind farms in fauna with a mathematical model

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Pablo Refoyo Román ◽  
Cristina Olmedo Salinas ◽  
Benito Muñoz Araújo
Keyword(s):  
Mathematical Model ◽  
Renewable Energy ◽  
Wind Turbines ◽  
Energy Production ◽  
Wind Farm ◽  
Considerable Increase ◽  
Wind Farms ◽  
Mathematical Algorithm ◽  
The World

Abstract Energy production by wind turbines has many advantages. The wind is a renewable energy that does not emit greenhouse gases and has caused a considerable increase in wind farms around the world. However, this type of energy is not completely free of impact. In particular, wind turbines displace and kill a wide variety of wild species what forces us to plan their location well. In any case, the determination of the effects of wind farms on fauna, especially the flying one, is difficult to determine and depends on several factors. In this work, we will try to establish a mathematical algorithm that allows us to combine all variables that affect the species with the idea of quantifying the effect that can cause the installation of a wind farm with certain characteristics in a given place. We have considered specific parameters of wind farms, the most relevant environmental characteristics related to the location of the wind farm, and morphological, ethological and legal characteristics in the species. Two types of assessment are established for the definitive valuation. Total Assessment and Weighted Assessment. Total Valuation is established based on a reference scale that will allow us to establish categories of affection for the different species while Weighted valuation allows us to establish which species are most affected.

Vibration reduction on city buses: Determination of optimal position of engine mounts

2010 ◽  
Vol 24 (7) ◽  
pp. 2198-2209 ◽  
Author(s):  
Ali El Hafidi ◽  
Bruno Martin ◽  
Alexandre Loredo ◽  
Eric Jego
Keyword(s):  
Vibration Reduction ◽  
Optimal Position ◽  
Engine Mounts

Determination of the cationic distribution in oxidic thin films by resonant X-ray diffraction: the magnetoelectric compound Ga2−xFexO3

2016 ◽  
Vol 49 (4) ◽  
pp. 1308-1314 ◽  
Author(s):  
Christophe Lefevre ◽  
Alexandre Thomasson ◽  
Francois Roulland ◽  
Vincent Favre-Nicolin ◽  
Yves Joly ◽  
...  
Keyword(s):  
Thin Films ◽  
Room Temperature ◽  
Element Distribution ◽  
X Ray Diffraction ◽  
X Ray ◽  
Site Distribution ◽  
X Ray Scattering ◽  
Cationic Distribution ◽  
Cationic Site

The cationic distribution is decisive for both the magnetic and electric properties of complex oxides. While it can be easily determined in bulk materials using classical methods such as X-ray or neutron diffraction, difficulties arise for thin films owing to the relatively small amount of material to probe. It is shown here that a full determination of the cationic site distribution in thin films is possible through an optimized processing of resonant elastic X-ray scattering experiments. The method is illustrated using gallium ferrite Ga2−xFexO3samples which have been the focus of an increasing number of studies this past decade. They indeed represent an alternative to the, to date, only room-temperature magnetoelectric compound BiFeO3. The methodology can be applied to determine the element distribution over the various crystallographic sites in any crystallized system.

scholarly journals The determination of the stresses in the wire of steel wire rope at clash on the block

2021 ◽  
Vol 1 (92) ◽  
pp. 184
Author(s):  
Nataliia Fidrovska ◽  
Andrii Lomakin ◽  
Serhii Khursenko ◽  
Viktoriia Nesterenko
Keyword(s):  
Considerable Increase ◽  
Steel Wire ◽  
Tensile Force ◽  
Point Contact ◽  
Considerable Influence ◽  
Compression Force ◽  
Method Of Calculation ◽  
Extra Effort ◽  
The Wire

The article considers the problem of determining the extra effort that occurs when the steel weir rope runsng and the bend on the block. In spite of that what questions of determining the strain in ropes of carrying machines dedicate very many of works different sciences to our time no definition method of calculation of additional strains of bend in rope in the time of bend on block. For define overall increase of length wire obtain at cover of rope on the block was examine site of rope from its point contact since block to exceed widen of elongation in side of straight rope. On transition site the rope have certain curvature which is small value in comparison since curvature rope at increase additional effort on transition site not create important influence. On this score extend additional effort on transition site examine however for the straight rope. On value overall increase of the length wire transition site can have considerable influence because on this site the wire can have considerable increase of the length which summarize with value elongation receipt widen which is in rope curve on block. Although the question of defining the forces of the ropes of  Considered  steel weir rope element, which goes from a straight section to the curved on the block is a subject of very many works. In this case there arise tensile force (or compression force), which leads to the destruction of weirs of the steel weir rope. The proposed new calculation, which is based on the classical theory, namely Hooke's law. A comparison of the calculated values with the experimental ones is made.

scholarly journals ABSORBER PERFORMANCE IMPROVEMENT THROUGH SOLVENT CONCENTRATION CHANGES TO REGULATE EMISSIONS FROM COMBUSTION SYSTEMS

2020 ◽  
Vol 1 (2) ◽  
Keyword(s):  
Removal Rate ◽  
Combustion Products ◽  
Reaction Scheme ◽  
Simulation Software ◽  
Evaluation Tool ◽  
Solvent Concentration ◽  
Complete Combustion ◽  
Aspen Hysys ◽  
Concentration Changes

This work highlighted the determination of the best concentration profile for the operation of an absorber with potential to cut down combustion products emissions from the complete combustion reaction scheme of a combustion system waste stream. The proposed solvent concentration had a range of 1.84%-2.20% of caustic entrainment, therefore further increase on the solvent concentration above 2.20% is not feasible. Incremental changes of 0.06% were made to assess the optimal concentration required for best absorber performance. A process simulation software, ASPEN HYSYS 8.6, was utilized to simulate the emissions profile with PENG-ROBINSON as the Vapour-Liquid Equilibrium evaluation tool in the software. The study found the performance of the absorber improved with a corresponding increase in the concentration with 2.20% giving the most efficient removal rate of 61.59%, 26.5% and 85.2% for SO2, CO2 and NO2, respectively. The study recommended that one veritable method of improving the performance of absorber systems is to increase the concentration of the alkali based solvent to cut down on emissions from flue gas systems.

scholarly journals OPTIMIZATION OF THE SOLAR COLLECTOR’S POSITION

2017 ◽  
Vol 7 (2) ◽  
pp. 12-14
Author(s):  
Bogdan Sydorchuk ◽  
Oleksandr Naumchuk ◽  
Paweł Mazurek
Keyword(s):  
Solar Energy ◽  
Computer Model ◽  
Solar Collector ◽  
Mathematic Model ◽  
Optimal Position ◽  
Optimal Values

: It is made the mathematic model of determining of the solar collector’s parameters, that allows to get its optimal values for any latitude at an any point of time. Also it is developed the computer model for determination of the daily influx of solar energy on the surface of the solar collector, which allows to determine its optimal position.

Analysis of functional methods for determining the optimal position of the mandible

2020 ◽  
Vol 25 (1) ◽  
pp. 22-25
Author(s):  
L. V. Dubova ◽  
S. S. Prisyazhnykh ◽  
N. V. Romankova ◽  
D. V. Malahov
Keyword(s):  
Temporomandibular Disorders ◽  
Load Test ◽  
Diagnostic Methods ◽  
Graphic Method ◽  
Optimal Position ◽  
Advantages And Disadvantages ◽  
Functional Methods ◽  
The Subject ◽  
Physiological Method

Relevance. The subject of the research is to compare different functional methods for determining the optimal position of the mandible.Purpose. To find the advantages and disadvantages of using various functional diagnostic methods to determine the optimal position of the mandible.Materials and methods. We conducted a literature review of the functional methods for determining the optimal position of the mandible in the treatment of patients with temporomandibular disorders. Nowadays different methods are used, such as anatomical and physiological method, bilateral manipulation, front deprogrammer, graphic method, aksiography, kineziography, TENS et al.Results. The method of bimanual manipulation and frontal deprogrammer determine the central relation when TMJ pathology is not expressed and the load test is negative. The graphic method evaluates the function of the temporomandibular joint, determines the optimal position of the mandible. TENS moves the lower jaw to a position of physiological rest. Kinesiography and Axiography determine the temporomandibular disorders and we can use them to dynamically monitor patients at all stages of treatment, monitor the determination of the optimal position of the mandible.Conclusion. From the results of this study, we can conclude that there are a lot of methods of functional diagnostics of TMJ, which help to determine the optimal position of the mandible. Everybody can choose their own set of methods, that let reduce the number of non-examined patients with temporomandibular disorders.

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