• The Plant Pathology Journal
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• v.19 no.3
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• pp.129-132
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• 2003

Fusarium wilt of cucumber caused by Fusarium oxy-sporum f. sp. cucumerinum is a serious vascular disease worldwide. Biological control of Fusarium wilt in several crops has been accomplished by introducing non-pathogenic Fusarium sup. and other biocontrol agents in soil or in infection courts. In this study, quantitative models were used to determine the biocontrol efficacy of inundatively applied antagonist formulations and the length of their effectiveness in controlling Fusarium wilt of cucumber. Quantitative model of the form [Y=L (1${-exp}^{-kx}$)] best described the relationship between disease incidence (Y, %) and inoculum density (X) of isolates F51 and F55. Isolate F51 was selected as a more virulent isolate based on the extent of its effectiveness in causing the wilt disease. The degree of disease control (Xi/X) obtained with the density of the biocontrol agent (Z), was described by the model [Xi/X=A (1${-exp}^{-cz}$)]. The zeolite-based antagonist formulation amended with chitosan (ZAC) was better at lower rates of application and peaked at around 5 g/ kg of the potting medium, whereas the peat-based antagonist formulation (PA) peaked at around 10 g/kg of the potting medium. ZAC formulation provided significantly better suppression of Fusarium wilt as described by the curvilinear relationship of the type Y= a+bX+c$X^2$, where Y represents percent disease incidence and X represents sustaining effect of the biocontrol agent.

• International Journal of Concrete Structures and Materials
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• v.3 no.1
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• pp.3-9
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• 2009

This paper examines the incorporation of the crushed sand (CS) and desert sand (DS) in the formation of self compacting concrete (SCC). These sands have been substituted for the rolled sand (RS), which is currently the only sand used in concretes and which is likely to run out in our country. DS, which comes from the Tunisian Sahara in the south, is characterized by a tight distribution of grains size. CS, a by-product of careers containing a significant amount of fines up to 15%, is characterized by a spread out granulometry having a maximum diameter of around 5mm. These two sands are considered as aggregates for the SCC. This first part of the study consists in analyzing the influence of the type of sand on the parameters of composition of the SCC. These sands consist of several combinations of 3 sands (DS, CS and RS). The method of formulation of the adopted SCC is based on the filling of the granular void by the paste. The CS substitution to the RS made it possible, for all the proportions, to decrease the granular voids, to increase the compactness of the mixture and to decrease the water and adding fillers proportioning. These results were also obtained for a moderate substitution of DS/CS (< 40%) and a weak ratio of DS/RS (20%). For higher proportions, the addition of DS to CS or RS did not improve the physical characteristics of the SCC granular mixture.

• Structural Engineering and Mechanics
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• v.24 no.6
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• pp.709-725
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• 2006

In this paper the buckling and post-buckling behavior of slender bars under self-weight are studied. In order to study the post-buckling behavior of the bar, a geometrically exact formulation for the non-linear analysis of uni-directional structural elements is presented, considering arbitrary load distribution and boundary conditions. From this formulation one obtains a set of first-order coupled nonlinear equations which, together with the boundary conditions at the bar ends, form a two-point boundary value problem. This problem is solved by the simultaneous use of the Runge-Kutta integration scheme and the Newton-Raphson method. By virtue of a continuation algorithm, accurate solutions can be obtained for a variety of stability problems exhibiting either limit point or bifurcational-type buckling. Using this formulation, a detailed parametric analysis is conducted in order to study the buckling and post-buckling behavior of slender bars under self-weight, including the influence of boundary conditions on the stability and large deflection behavior of the bar. In order to evaluate the quality and accuracy of the results, an experimental analysis was conducted considering a clamped-free thin-walled metal bar. As this kind of structure presents a high index of slenderness, its answers could be affected by the introduction of conventional sensors. In this paper, an experimental methodology was developed, allowing the measurement of static or dynamic displacements without making contact with the structure, using digital image processing techniques. The proposed experimental procedure can be used to a wide class of problems involving large deflections and deformations. The experimental buckling and post-buckling behavior compared favorably with the theoretical and numerical results.

• Computational Structural Engineering
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• v.7 no.4
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• pp.103-111
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• 1994

Based on a variational principle of the consistent shear deformable discrete laminate theory derived in the companion paper Part I, a finite element procedure for the vibration analysis of laminated composite plates is presented. The present formulation takes the in-plane displacements of an arbitrary layer, the rotations of the cross section of each layer and transverse displacement of the plate as the state variables at a nodal point of finite element, resulting in total nodal degree of freedom of 2(n+l) +1 for the n-layered laminate. Thus, it allows to specify displacement boundary conditions of layer stretching and/or rotation of layer cross sections around the plate edge and/or lateral displacement. The developed procedure is applied to the free vibration problem for sandwich-type hybrid laminates composed of layers with drastically different material properties whose elasticity solutions are known. Comparison of analysis results with other FEM solutions showed that the present formulation yields better accuracy.

• Journal of Pharmaceutical Investigation
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• v.34 no.2
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• pp.131-138
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• 2004

This study was aimed to investigate the feasibility of nasal delivery of caffeine for the elimination of sleepiness. The effects of various vehicles, solubilizers, and enhancers on the permeation of caffeine through rabbit nasal mucosa was observed. The permeation study was carried out using a Franz-type permeation system at $37^{\circ}C$, and the amount of caffeine permeated though the rabbit nasal mucosa was determined by a validated HPLC. The apparent solubility and phys iochemical stability of caffeine in various nasal formulations were was determined. The effect of hydrotropes and modified cyclodextrins on the solubility of caffeine in water was determined by equilibrium solubility method. The solubility of caffeine in water was 29 mg/mL at $30^{\circ}C$. The addition of sodium benzoate and nicotinamide at 10% improved the solubility of caffeine (115 and 132 mg/mL, respectively) in aqueous solution. The flux of caffeine though the nasal mucosa from aqueous solution was $2.1{\pm}0.26\;mg/cm^2/hr$. The addition of sodium benzoate reduced its permeation $(1.4{\pm}0.01\;mg/cm^2/hr)$, but sodium benzoate with 5% $2HP{\beta}CD$ and 0.03% monoterpenes increased its permeation $(2.4{\pm}0.04\;mg/cm^2/hr)$ markedly. The addition of nicotinamide also increased also increased its permeation $(2.5{\pm}0.36\;mg/cm^2/hr)$. markedly. As the concentration of caffeine in nasal formulation increased, the permeation flux increased linearly. Caffeine was stable physicochemically and enzymatically in the nasal mucosa extract at $37^{\circ}C$. These results suggest that caffeine can be efficiently delivered nasally and the development of nasal formulation will be feasible.

• Applied Chemistry for Engineering
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• v.16 no.6
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• pp.827-833
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• 2005

This study focused on the establishment of optimum formulation of polyamide based hot melt adhesive through adhesive synthesis, study of physical property, and adhesion study. In the previous study, the optimum formulation of base resins (CM831, 843P) and tackifying resin (terpene resin) was determined. The weight ratio of CM831, 843P, and terpene resin was 75, 25, and 10, respectively. Based on the optimum formulation, the effect of wax and filler addition was examined in this study. According to the results, the maximum adhesion strength with the steel could be obtained by the addition of 5 wt% of polyethylene wax although the melt viscosity of adhesive decreased continuously with the addition of wax. In the case of filler, the optimum adhesion property could be achieved by the addition of 10 wt% of talc. However, the addition of filler caused little increase of melt viscosity of adhesive.

• Journal of the Korean Applied Science and Technology
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• v.38 no.4
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• pp.1176-1182
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• 2021

In this study, the emulsion stability of henna, a natural hair dye, according to the content of cetyl alcohol, one of the emulsification stabilizers, was analyzed, and the content of cetyl alcohol showing the most stable emulsification was confirmed. To analyze the emulsion stability, differences in particle size, particle shape, viscosity, and color after dyeing were compared according to the content of cetyl alcohol. As a result of dynamic light scattering (DLS) zeta analysis, cetyl alcohol 3% showed the highest zeta potential value of 115.9 mV, and the particle size distribution was henna in which a cream-type hair dye containing 3% cetyl alcohol was dispersed in distilled water. The width of the particle size distribution was narrow compared to. As a result of viscometer analysis, the viscosity increased as the content of cetyl alcohol increased. As a result of measuring the henna pH of the cream formulation, it was measured in a pH range suitable for the scalp. As a result, emulsion stability increases as the content of cetyl alcohol increases in henna cream formulations for hair dye.

• Applied Chemistry for Engineering
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• v.30 no.4
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• pp.415-420
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• 2019

To investigate the effect of nonionic surfactant and emulsion stabilizer on O/W emulsions, various emulsion formulations with different types of nonionic surfactants and emulsion stabilizers were prepared and their rheological properties were compared. In this study, polysorbate 60 (Tween 60), PEG-60 hydrogenated castor oil (HCO 60), octyldodeceth-16 (OD 16), and ceteareth-6 olivate (Olivem 800) were used as hydrophilic nonionic surfactants, whereas cetyl alcohol, glyceryl monostearate, and stearic acid as emulsion stabilizers. Phase separation occurred only in the emulsion formulation with octyldodeceth-16 and all other emulsion formulations maintained a stable phase. The viscosity, hardness, and creaminess of emulsion formulation using a mixture of ceteareth-6 olivate and cetyl alcohol were the highest, and the emulsified droplet size was also the largest. These results are due to the formation of a network structure texture with the development of a large amount of liquid crystal in the O/W emulsion. In this formulation, the value of elastic modulus was large and the thixotropic behavior, in which the viscosity varies with the history of external force, was observed.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.46 no.4
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• pp.383-390
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• 2020

Blue light is a blue-based light existing at a wavelength between 380 and 450 nm, and it has been reported that it induces active oxygen and causes aging, and accordingly, interest in the blue light blocking effect is increasing. In this study, the effects of the polarity of oil, viscosity of the formulation, type of emulsifier, emulsified particles, and inorganic UV blocking agents on the blue light blocking effect in UV blocking products were investigated. As a result, it was confirmed that the blue light blocking rate increased as the polarity of the oil became similar to that of the organic UV blocker, and the higher the viscosity of the formulation, the higher the blue light blocking rate. The types of emulsifiers and emulsified particles had little effect on the blue light blocking effect, and the presence of inorganic UV blocking agents was found to be one of the factors that greatly influenced the blue light blocking rate. These results can effectively increase the efficiency of blocking blue light, and may be used in the development of blue light blocking products and formulation research in the future.

• Smart Structures and Systems
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• v.30 no.3
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• pp.221-237
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• 2022

This paper is concerned with nonlinear modeling and efficient numerical simulation of electrostrictive materials and structures. Two types of such materials are considered: relaxor ferroelectric ceramics and electrostrictive polymers. For ceramics, a geometrically linear formulation is developed, whereas polymers are studied in a geometrically nonlinear regime. In the paper, we focus on constitutive modeling first. For the reversible constitutive response under consideration, we introduce the augmented Helmholtz free energy, which is composed of a purely elastic part, a dielectric part and an augmentation term. For the elastic part, we involve an additive decomposition of the strain tensor into an elastic strain and an electrostrictive eigenstrain, which depends on the polarization of the material. In the geometrically nonlinear case, a corresponding multiplicative decomposition of the deformation gradient tensor replaces the additive strain decomposition used in the geometrically linear formulation. For the dielectric part, we first introduce the internal energy, to which a Legendre transformation is applied to compute the free energy. The augmentation term accounts for the contribution from vacuum to the energy. In our formulation, the augmented free energy depends not only on the strain and the electric field, but also on the polarization and an internal polarization; the latter two are internal variables. With the constitutive framework established, a Finite Element implementation is briefly discussed. We use high-order elements for the discretization of the independent variables, which include also the internal variables and, in case the material is assumed incompressible, the hydrostatic pressure, which is introduced as a Lagrange multiplier. The elements are implemented in the open source code Netgen/NGSolve. Finally, example problems are solved for both, relaxor ferroelectric ceramics and electrostrictive polymers. We focus on thin plate-type structures to show the efficiency of the numerical scheme and its applicability to thin electrostrictive structures.