Determination of the yield function and its derivatives of the Barcelona Expansive model

MATEC Web of Conferences ◽

10.1051/matecconf/201814902033 ◽

2018 ◽

Vol 149 ◽

pp. 02033

Author(s):

Jamila El Brahmi ◽

Nouzha Lamdouar ◽

Mimoun Zoukaghe

Keyword(s):

Expansive Soils ◽

Yield Function ◽

Elastoplastic Problem ◽

Stress Vector ◽

Partial Derivatives ◽

Hardening Parameter ◽

Unsaturated Expansive Soils ◽

Derivatives Of

The main purpose of this paper is to determine the yield function F of the Barcelona Expansive Model and its partial derivatives with respect to the stress vector σ, the suction s and the hardening parameter χ. These results are important by the fact that they are used to solve the elastoplastic problem of unsaturated expansive soils.

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Simultaneous determination of eight derivatives of propranolol in cornea perfusate in vitro by high performance liquid chromatography

Chinese Journal of Chromatography ◽

10.3724/sp.j.1123.2012.06039 ◽

2013 ◽

Vol 30 (11) ◽

pp. 1183-1187

Author(s):

Haitao WU ◽

Chuanbing CHEN ◽

Ningsheng WANG ◽

Suiqing MI ◽

Nanying LIAO

Keyword(s):

High Performance Liquid Chromatography ◽

Liquid Chromatography ◽

Simultaneous Determination ◽

High Performance ◽

Derivatives Of

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Spectrophotometric study of the complexation equilibria of cadmium ions with 5-bromo and 5-chloro derivatives of 2-(2-pyridylazo)-5-diethylaminophenol (BrPADAP, ClPADAP)

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19830052 ◽

1983 ◽

Vol 48 (1) ◽

pp. 52-59 ◽

Cited By ~ 4

Author(s):

Vlastimil Kubáň ◽

Miroslav Macka

Keyword(s):

Equilibrium Constants ◽

Spectrophotometric Study ◽

Graphical Analysis ◽

Optimal Conditions ◽

Cadmium Ions ◽

Brij 35 ◽

Ethanol Medium ◽

Triton X ◽

Derivatives Of

The composition, optical characteristics, molar absorption coefficients and equilibrium constants of the reactions of formation of the ML and ML2 complexes of both reagents with cadmium(II) ions were determined by graphical analysis and numerical interpretation of the absorbance-pH curves by the modified SQUAD-G program. Optimal conditions were proposed for the spectrophotometric determination of Cd in 10% v/v ethanol medium in the presence of 0.1% w/v Triton X-100 or 1% w/v Brij 35. BrPADAP and ClPADAP are the most sensitive spectrophotometric reagents for the determination of cadmium(II) ions (ε = 1.28-1.44 . 105 mmol-1 cm2 at 560 nm and pH 8.0-9.5) with a high colour contrast in the reaction (Δλmax ~117 nm) and a selectivity similar to that of other N-heterocyclic azodyes (PAR, PAN, etc.).

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Spectrophotometric study of the acid-base and optical properties of the 5-bromo and 5-chloro derivatives of 2-(2-pyridylazo)-5-(diethylamino)phenol (BrPADAP, ClPADAP) and their complexation equilibria with zinc(II) ions

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19822676 ◽

1982 ◽

Vol 47 (10) ◽

pp. 2676-2691 ◽

Cited By ~ 6

Author(s):

Miroslav Macka ◽

Vlastimil Kubáň

Keyword(s):

Equilibrium Constants ◽

Spectrophotometric Study ◽

Graphical Analysis ◽

Alkaline Media ◽

Acid Base ◽

Ethanol Medium ◽

Triton X ◽

Mixed Water ◽

Derivatives Of

The optical and acid-base characteristics of BrPADAP and ClPADAP were studied in mixed water-ethanol and water-DMF media and in 10% ethanol medium in the presence of cationic, anionic and nonionic tensides. The composition, optical characteristics, molar absorption coefficients and equilibrium constants of the ML and ML2 complexes with zinc(II) ions were found by graphical analysis and numerical interpretation of the absorbance curves by the modified SQUAD-G program. Optimal conditions were found for the spectrophotometric determination of Zn(II) in the presence of 0.1% Triton X-100 or 1% Brij 35 in alkaline media with pH = 6.5-10. BrPADAP and ClPADAP are the most sensitive reagents (ε = 1.3-1.6 . 105 mmol-1 cm2 at 557 and 560 nm, respectively) for the determination of zinc with high colour contrast of the reaction (Δλ = 104 nm) and selectivity similar to that for the other N-heterocyclic azodyes (PAN, PAR, etc.).

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