Results 241 to 250 of about 1,790,903 (284)

Upper and lower critical solution temperatures in poly (ethylene glycol) solutions

Polymer, 1976
Upper and lower critical solution temperatures have been determined for solutions of poly(ethylene glycol) in t-butyl acetate and water over the molecular weight range of Mη = 2.18 × 103 to ∼1020 × 103. The phase diagram for solutions of poly(ethylene glycol) (Mη = 719 × 103) in t-butyl acetate was expressed as the ‘hour glass’ type, while the phase ...
Susumu Saeki, Nobuhiro Kuwahara, Mitsuo Nakata, Motozo Kaneko   +3 more
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Foliations, associated reductions and lower and upper solutions

2002
In this interesting paper, the authors answer \textit{J. Mawhin}'s question [Boll. Unione Mat. Ital., VI. Ser., A 3, 229-238 (1984; Zbl 0547.34032)] in establishing the existence of a solution to the periodic boundary value problem \[ u''(t) + g(t,u(t)) = 0, \quad u(0)=u(T), \quad u'(0)=u'(T), \] for \(g\) asymptotically linear and satisfying a ...
C. De Coster, M.E. Tarallo
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Lower and Upper Solutions of Boundary Value Problems

2003
The method of lower and upper solutions, coupled with the monotone iterative technique provides an effective and flexible mechanism that offers theoretical as well as constructive existence results for nonlinear problems in a closed set which is generated by the lower and upper solutions.
Elvan Akin-Bohner, Ferhan Merdivenci Atici, Billûr Kaymakçalan   +2 more
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Invariance, Comparison, and Upper and Lower Solutions

1996
This chapter establishes invariance and various inequalities for solutions of abstract integral equations with delay.
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Singular problems motivated from classical upper and lower solutions

Acta Mathematica Hungarica, 2003
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Agarwal, R. P., O'Regan, D.
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Upper and lower solution estimates in unilateral viscoelastodynamics

Acta Mechanica, 1987
The variational and bounding method of hypercircle for linear, elliptic, boundary-value problems of mathematical physics [e.g. \textit{W. Velte}, Direkte Methoden der Variationsrechnung (1976; Zbl 0333.49035)], is extended in this paper to inequality, evolution problems of time- dependent structural mechanics.
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An upper and lower solution theory for singular Emden–Fowler equations

Nonlinear Analysis: Real World Applications, 2002
Results guaranteeing the existence of positive solutions to the Dirichlet boundary value problem \[ y''+ q(t) f(t,q)= 0,\quad 0< t< 1,\quad y(0)= 0= y(1),\tag{\(*\)} \] are obtained. Here, \(f: [0,1]\times (0,\infty)\to \mathbb{R}\) is continuous and may be singular at \(y= 0\), \(q\in C(0,1)\), \(q> 0\) on \((0,1)\) and \(\int^1_0 x(1- x)q(x) dx ...
Agarwal, R.P., O'Regan, D., Lakshmikantham, V., Leela, S.   +3 more
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Upper and Lower Solutions Method and a Singular Boundary Value Problem

ZAMM, 2002
The article is devoted to the boundary value problem \[ u''+ g(t,u,u')= 0,\quad t\in (0,1),\quad u(0)= u(1)= 0. \] It is assumed that the problem may be singular at \(t= 0\), \(t=1\), and \(u= 0\). The technique of upper and lower solutions is used to obtain sufficient conditions for the solvability.
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Upper and lower critical solution temperatures in 1‐octanol solutions of polyethylene

British Polymer Journal, 1983
AbstractCloud points of 1‐octanol solutions of four linear polyethylene samples having different molecular weights were measured visually in both regions of the upper and lower critical solution temperatures (UCST and LCST). From the (temperature, polymer weight fraction) phase diagrams drawn, the UCST and LCST were determined.
Yoichiro Muraoka, Hiroshi Inagaki, Hidematsu Suzuki   +2 more
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Designing modern aqueous batteries

Nature Reviews Materials, 2022
Yanliang Liang, Yan Yao
exaly