scholarly journals Characterization of aluminum honeycomb and experimentation for model development and validation :volume II, honeycomb experimentation for model development and validation.

2006 ◽  
Author(s):  
Eric Carl Stasiunas ◽  
Wei-Yang Lu ◽  
Michael K Neilsen ◽  
Thomas Glen Carne ◽  
Terry Dean Hinnerichs ◽  
...  
Keyword(s):  
Model Development ◽  
Aluminum Honeycomb ◽  
Development And Validation

FEM Modelling of Recrystallization Behaviour for Near-Alpha Ti Alloy IMI834

2010 ◽  
Vol 89-91 ◽  
pp. 592-597 ◽  
Author(s):  
Phuong Vo ◽  
Mohammad Jahazi ◽  
Steve Yue
Keyword(s):  
Model Development ◽  
Element Model ◽  
Strain Rates ◽  
Ti Alloy ◽  
Commercial Code ◽  
Alpha Titanium ◽  
Alpha Beta ◽  
Development And Validation ◽  
Deform 3D

The recrystallization behaviour of near-alpha titanium alloy IMI834, which is primarily used for high temperature aerospace compressor disc applications, has been investigated at hot working temperatures. The latest results of a finite element model, developed using the commercial code DEFORM-3D with constitutive equations adapted from available literature, will be presented. Model development and validation involved the hot compression of specimens with an initial bimodal alpha+beta microstructure at temperatures of 1000°C-1100°C, strain rates of 0.01s 1-1s 1, and varied post-deformation annealing times. The characterization of microstructure through quantitative metallography revealed beta grain refinement achieved primarily through static/metadynamic recrystallization. The beta recrystallization kinetics were subsequently predicted through an Avrami-type relationship.

Treatment system response to transient AOX (adsorbable organic halogen) loadings

1997 ◽  
Vol 35 (2-3) ◽  
pp. 85-91
Author(s):  
D. A. Barton ◽  
J. D. Woodruff ◽  
T. M. Bousquet ◽  
A. M. Parrish
Keyword(s):  
Paper Industry ◽  
Model Development ◽  
Operating Conditions ◽  
System Response ◽  
Additional Information ◽  
Organic Halogen ◽  
Aox Removal ◽  
Variable Operating Conditions ◽  
Plant Shutdown

If promulgated as proposed, effluent guidelines for the U.S. pulp and paper industry will impose average monthly and maximum daily numerical limits of discharged AOX (adsorbable organic halogen). At this time, it is unclear whether the maximum-day variability factor used to establish the proposed effluent guidelines will provide sufficient margin for mills to achieve compliance during periods of normal but variable operating conditions within the pulping and bleaching processes. Consequently, additional information is needed to relate transient AOX loadings with final AOX discharges. This paper presents a simplistic dynamic model of AOX decay during treatment. The model consists of hydraulic characterization of an activated sludge process and a first-order decay coefficient for AOX removal. Data for model development were acquired by frequent collection of influent and effluent samples at a bleach kraft mill during a bleach plant shutdown and startup sequence.

A Simple, Green and Fast Ultraviolet Spectrophotometric Method for the Carbamide Peroxide Determination in Dental Whitening Products

2019 ◽  
Vol 15 (2) ◽  
pp. 138-144
Author(s):  
Fabiana Vieira Lima ◽  
Aline Farias ◽  
Cassiana Mendes ◽  
Simone Gonçalves Cardoso ◽  
Marcos Antônio Segatto Silva
Keyword(s):  
Hydrogen Peroxide ◽  
Pharmaceutical Products ◽  
Reference Solution ◽  
Iodometric Titration ◽  
Carbamide Peroxide ◽  
Ultraviolet Detection ◽  
Water As Solvent ◽  
Development And Validation ◽  
Dental Whitening

Background: The carbamide peroxide is the most commonly active ingredient used for home dental whitening products, its quantification in pharmaceutical products is of extreme importance due to the relation with the products potency and the previously related low carbamide peroxide stability. Once, there is only one official carbamide peroxide determination based on iodometric titration, this method is time-consuming and generates a lot of residues. The aim of this study was to carry out development and validation of a simple and fast ultraviolet spectrophotometer assay to quantify an innovative dental whitening gel. Methods: The proposed method was validated according international conference on harmonization guideline. Procedure is based on the iodide/iodine redox chemistry; iodine released through the action of hydrogen peroxide of carbamide peroxide with ultraviolet detection at 350 nm. Results: The procedure was linear in the concentration range of 1.0-4.0 µg/mL, specific to the excipients, robust for the evaluated parameters (variation of wavelength (± 5 nm); reagent addition (± 10%)), showing the results of RSD 1.88 and 0.39% respectively. Repeatability precision was RSD = 1.42%, with accurate RSD = 2.15% by adding reference solution. The assay used only water as solvent for sample preparation. In comparison to the pharmacopeial method, the latter is more time-consuming, as it generates a lot of residues, and it could not quantify small CP dosages. Conclusion: Thus, the proposed method was proved to be suitable to determine carbamide peroxide during the development and characterization of nanoparticle formulations in the present study.

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