R-Curve Determination Using a Crack-Line-Wedge-Loaded (CLWL) Specimen

2009 ◽  
pp. 17-17-19 ◽  
Author(s):  
DE McCabe ◽  
RH Heyer
Keyword(s):  
Crack Line ◽  
Curve Determination

pH Dependent Release Potential of Natural Polymers in Sustained Release of Ornidazole From Colon Targeted Delivery System)

2019 ◽  
Vol 9 (02) ◽  
Author(s):  
Sharma Pankaj ◽  
Tailang Mukul
Keyword(s):  
Drug Release ◽  
Delivery System ◽  
Targeted Delivery ◽  
Guar Gum ◽  
Acidic Environment ◽  
Natural Polymers ◽  
Weight Variation ◽  
Curve Determination ◽  
Preformulation Studies

The aim of present work was to prepare colon specific delivery system of Ornidazole using different ratio of shellac, zein and guar gum. From study of various literature it revealed that shellac, zein and guar gum released drug from dosage form at the pH of 6.9, 11.5, 7-9 respectively. The main problem associated with colon targeted drug delivery system is degradation of drug in the acidic environment of stomach to circumvent the present problem different combinations of shellac, zein and guar gum were employed in the formulation of colon targeted tablet. Several preformulation parameters were determined such as melting point, FTIR spectroscopy, preparation of calibration curve, determination of λmax and partition coefficient. After the preformulation studies, next steps were preparation of core tablets, evaluation of core of tablets and coating of tablets. The data obtained from preformulation study seven formulations were developed and evaluated for various parameters. Based on evaluated parameter such as weight variation, friability, dissolution study, invitro drug release etc. the F7 formulation show better results colon targeted tablets. Drug content in F7 formulation was 95% and drug release after 6 hrs was 96%. Formulation containing combination of shellac, zein and guar gum released least amount of drug in the acidic environment of stomach and released most of the drug in colon. It is evide

Thermodynamic and Kinetic Calculation of Non-Equilibrium Microstructure Design of TRIP Steel

2014 ◽  
Vol 783-786 ◽  
pp. 766-770
Author(s):  
Yan Lin He ◽  
Na Qiong Zhu ◽  
Wei Sen Zheng ◽  
Xiao Gang Lu ◽  
Lin Li
Keyword(s):  
Trip Steel ◽  
Equilibrium Phase ◽  
Microstructure Design ◽  
Kinetic Calculation ◽  
Software Comparison ◽  
Thermo Calc Software ◽  
Curve Determination ◽  
Equilibrium Microstructure ◽  
The Relationship ◽  
Non Equilibrium

The non-equilibrium microstructure of Fe-C-Mn-Si TRIP steel is designed bythermodynamic and kinetic calculation. The upper limit of bainitic transformation temperature iscalculated and compared to that characterized by CCT curve determination. s M temperature isdetermined based on thermodynamics of martensitic transformation and sublattice model. Thecalculation is conducted via TQ6-patch in Thermo-Calc software. Comparison between thecalculations and experiments reveals the relationship between non-equilibrium phase compositionand heat treatment parameters which can be utilized to achieve the elaborate design of alloy and heattreatment for super TRIP steel.

Elasto-Plastic Fracture Analysis of Finite-Width Cracked Stiffened Plate

2014 ◽  
Vol 496-500 ◽  
pp. 1052-1057 ◽  
Author(s):  
Jun Lin Deng ◽  
Ping Yang ◽  
Qin Dong ◽  
Xiang Yan
Keyword(s):  
Field Method ◽  
Uniaxial Tensile ◽  
Small Scale ◽  
Finite Width ◽  
Stiffened Plate ◽  
Line Field ◽  
Strain Fields ◽  
Zone Length ◽  
Crack Line ◽  
Crack Tips

Thispaper adopts the crack line-field method to analyze finite-width stiffenedplates with central through I-type crack under uniaxial tensile loading. Themethod completely abandons the small scale yield hypothesis. The plastic stressand strain fields at crack tips and the plastic-zone length can be accurately determinedby combining with equivalent shear stress of Westergaard stress function in theposition of stiffener. It can be seen from the illustrative example that theresults of the paper agree well with those by finite element method.

Fiber Debonding Along a Crack Front in Paper

1998 ◽  
Vol 539 ◽  
Author(s):  
H. Kettunen ◽  
K. J. Niskanen
Keyword(s):  
Fracture Energy ◽  
Crack Front ◽  
Fracture Process ◽  
Fracture Process Zone ◽  
Process Zone ◽  
Bond Properties ◽  
Crack Line ◽  
Pull Out ◽  
Microscopic Damage ◽  
Debonding Process

AbstractWe follow the accumulation of microscopic damage ahead the crack tip in paper. The fiber debonding process varies even within each specimen because of large variation in fiber and bond properties. In general, stiff and weakly bonded fibers tend to debond as a rigid body while ductile or well bonded fibers pull out gradually in a process that propagates from the crack line to the fiber ends. Particularly in the latter case the network ruptures coherently rather than through debonding of single fibers. Experimental analysis and simulations show that fracture energy correlates closely with the size of the fracture process zone (FPZ) irrespective the nature of the debonding process. Only the cases of low bonding and stiff fibers seem to make an exception in that FPZ can grow in size without a corresponding increase in fracture energy.

Vapor pressure curve determination of α-lipoic acid raw material and capsules by dynamic thermogravimetric method

2012 ◽  
Vol 544 ◽  
pp. 95-98 ◽  
Author(s):  
Alyne da Silva Portela ◽  
Maria das Graças Almeida ◽  
Ana Paula Barreto Gomes ◽  
Lidiane Pinto Correia ◽  
Paulo Cesar Dantas da Silva ◽  
...  
Keyword(s):  
Vapor Pressure ◽  
Lipoic Acid ◽  
Raw Material ◽  
Pressure Curve ◽  
Thermogravimetric Method ◽  
Vapor Pressure Curve ◽  
Curve Determination

Melting curve determination for cerium up to 30 GPa

1994 ◽  
Author(s):  
B. Sitaud ◽  
J. Péré ◽  
Th. Thévenin
Keyword(s):  
Melting Curve ◽  
Curve Determination

scholarly journals Evolution Model for Epidemic Diseases Based on the Kaplan-Meier Curve Determination

Mathematics ◽  
2020 ◽  
Vol 8 (8) ◽  
pp. 1260
Author(s):  
Jose M. Calabuig ◽  
Luis M. García-Raffi ◽  
Albert García-Valiente ◽  
Enrique A. Sánchez-Pérez
Keyword(s):  
Real Data ◽  
Local Minima ◽  
Global Minima ◽  
Huge Number ◽  
Quadratic Error ◽  
Kaplan Meier ◽  
Starting Point ◽  
Curve Determination ◽  
Epidemic Diseases

We show a simple model of the dynamics of a viral process based, on the determination of the Kaplan-Meier curve P of the virus. Together with the function of the newly infected individuals I, this model allows us to predict the evolution of the resulting epidemic process in terms of the number E of the death patients plus individuals who have overcome the disease. Our model has as a starting point the representation of E as the convolution of I and P. It allows introducing information about latent patients—patients who have already been cured but are still potentially infectious, and re-infected individuals. We also provide three methods for the estimation of P using real data, all of them based on the minimization of the quadratic error: the exact solution using the associated Lagrangian function and Karush-Kuhn-Tucker conditions, a Monte Carlo computational scheme acting on the total set of local minima, and a genetic algorithm for the approximation of the global minima. Although the calculation of the exact solutions of all the linear systems provided by the use of the Lagrangian naturally gives the best optimization result, the huge number of such systems that appear when the time variable increases makes it necessary to use numerical methods. We have chosen the genetic algorithms. Indeed, we show that the results obtained in this way provide good solutions for the model.

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