Formation of hydrophilic starch coatings on polyethylene films

Thin starch coatings were deposited onto polyethylene (PE) film surfaces when PE films were immersed in 1% jet cooked starch solutions and the hot solutions were allowed to cool. Normal cornstarch, waxy cornstarch, high amylose cornstarch, and solvent‐extracted normal cornstarch (to remove native lipid) were used in these experiments. Amounts of adsorbed starch varied from about 0.03–0.05 mg per cm² of PE, and these starch coatings imparted hydrophilic properties to film surfaces, as evidenced by contact angle measurements. Although starch could be removed by gently rubbing water‐wet PE surfaces, air‐dried coatings were more firmly attached, and did not separate from the PE surface when films were bent or flexed. SEM images of starch‐coated film surfaces showed that starch was deposited as particles less than 1 μm in diameter, and also as aggregates of these submicron particles. Despite the fact that some starch samples contained only very small amounts of amylose and native lipid, surface‐deposited starch in all experiments contained 90–100% amylose; and exhibited the same V_h X‐ray diffraction pattern, indicative of helical inclusion complex formation. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1781–1788, 2002; DOI 10.1002/app.10589     

Dissolution and Separation of Aluminum and Aluminosilicates

Selection of an aluminum alloy for target cladding affects post-irradiation target dissolution and separations. Recent tests with aluminum alloy 6061 yielded greater than expected precipitation in the dissolver, forming up to 10 wt.% solids of aluminum hydroxides and aluminosilicates. Aluminosilicate dissolution presents challenges in a number of different areas, including metals extraction from minerals, flyash treatment, and separations from aluminum alloys. We present experimental work that attempts to maximize dissolution of aluminum metal in caustic, along with silicon, magnesium, and copper impurities, through control of temperature, the rate of reagent addition, and incubation time. Aluminum phase transformations have been identified as a function of time and temperature, using X-ray diffraction. Solutions have been analyzed using wet chemical methods and X-ray fluorescence. These data have been compared with published calculations of aluminum phase diagrams. Approaches are given to enhance the dissolution of aluminum and aluminosilicate phases in caustic solution.     

Baseball implant. A method of secondary insertion of an intraorbital implant

A surgical technique for secondary emplacement of an orbital implant is described in which a spherical implant encased in a scleral homograft is placed in the orbit through a transconjuctival incision and sutured to the superior part of the periosteum.     

Graft polymerization of acrylonitrile onto starch‐coated polyethylene film surfaces

Starch‐coated polyethylene (PE) films were prepared by immersing PE in a hot, jet cooked solution of starch. They were allowed to react with acrylonitrile (AN) in the presence of ceric ammonium nitrate initiator, and the graft polymerization that occurred produced starch‐g‐polyacrylonitrile (PAN) coatings that contained about 25 wt % grafted PAN. The starch‐g‐PAN coatings tightly adhered to the PE film surfaces. When grafted starch coatings were wetted with water and the surfaces vigorously rubbed, less than 20% of the coating was removed. The fact that PAN‐grafted coatings were not removed with boiling water provided further evidence for their strong adherence. When starch was removed from the coating by acid hydrolysis, the residual grafted PAN still remained adsorbed on the PE surface. Because the grafted coating was completely removed by treatment with refluxing 0.7N sodium hydroxide, there is apparently no chemical bonding between starch‐g‐PAN and PE. The dimensional changes associated with the evaporation of water from these PAN‐grafted coatings caused the films to curl during drying. Because the final shape of these coated films depends upon the presence or absence of water in the surrounding environment, these films may be considered to be a type of stimulus‐responsive polymer. Attempts to graft polymerize methyl methacrylate and methyl acrylate onto starch‐coated PE surfaces, under conditions similar to those used with AN, were unsuccessful. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3323–3328, 2003     

Characteristics of Low-fat Beef Patties Formulated with Carbohydrate-Lipid Composites

ABSTRACT: Chemical, physical, and sensory characteristics of low-fat beef patties containing carbohydrate-lipid composites (CLCs) were compared with those of all-beef patties. The CLC gels contained high-amylose cornstarch, maltodextrins, and canola oil. CLC patties had higher moisture, cooking yield, and fat retention than 20%-fat control patties. CLCs improved tenderness and juiciness and decreased cohesiveness of low-fat beef patties compared with 10%-fat control patties. Despite differences in CLC gel firmness, patties made with CLC gels containing corn, potato, and tapioca maltodextrins had similar physical and sensory properties. These results suggest that CLC gels perform well as a partial fat replacer in beef patties while providing flexibility in gel firmness selection.     

Investigation of the mechanism of lubrication in starch–oil composite dry film lubricants

The boundary coefficient of friction (COF) of starch–oil composite dry film lubricants was investigated as a function of starch type (waxy vs. normal purified food grade corn starch), oil chemistry (hexadecane vs. oleic acid and various vegetable oils), and starch‐to‐oil ratio. Based on the results, a mechanism of starch–oil interaction in these composites was proposed. According to the proposed mechanism: (a) the oil in the composite is distributed between the bulk and the surface of the starch; and (b) the fraction of the oil trapped in the bulk and that adsorbed on the surface are related to each other by an equilibrium constant, and are functions of the total oil concentration in the composite. In line with the proposed mechanism, an adsorption model was used to quantify the free energy of adsorption (ΔG_ads) of the polar oils onto the starch surface. The analysis gave ΔG_ads values that were higher than those reported for the adsorption of the same polar oils onto steel surfaces. This result is consistent with the effect of the relative surface energies of steel and starch on the adsorption of polar oils. The adsorption property of the non‐polar hexadecane relative to the polar oils was estimated by comparing their interfacial tensions with starch. The result showed a higher interfacial tension for hexadecane–starch than that for the polar oil–starch composites. This result predicts a relatively poorer compatibility with, and, hence, poorer adsorption of hexadecane onto starch leading to higher COF, as was observed in the friction measurements. Published in 2006 by John Wiley & Sons, Ltd.     

Starch‐filled ternary polymer composites. II: Room temperature tensile properties

The room temperature tensile properties of granular starch‐filled low‐density polyethylene (PE) and starch‐filled blends of PE and poly(hydroxy ester ether) (PHEE) are presented. At low filler contents (?_f), the filled PE:PHEE blend has a higher yield stress and tensile strength than either the starch/PE composites or the unfilled matrix. The increase in the yield stress indicates that matrix yielding occurs before debonding. At high filler contents, the tensile strength of the filled blend is again greater than the strength of the starch/PE composites. This increase in strength is the result of higher debonding stresses in the ternary composite. In both materials there is a change in the deformation process at a critical filler content, ?_cr. Below ?_cr, deformation involves the growth of debonded regions; above ?_cr, deformation is confined to narrow damaged zones. There is a reduction in the strain at failure when this change in the deformation process occurs. Although the PHEE surface coating affects the debonding stress and the tensile strength, it does not affect the strain at failure or the tensile modulus. For both composite materials, the increase in modulus with ?_f can be adequately described using a simplified form of the Kerner equation. Polym. Eng. Sci. 44:1839–1847, 2004. © 2004 Society of Plastics Engineers.     

Role of affective meaningfulness and self-concept in the verbal learning styles of White and Black children.

White and Black 5th graders, representing 2 social class and 2 self-concept (Piers-Harris Self-Concept Scale) levels, recalled nouns which they had prerated for likability in a multitrial free recall format. While self-concept failed to have any noticeable influence on the total sample, it interacted significantly with race. As predicted, the high self-concept White Ss recalled positively rated words more readily than negatively rated words, while their low self-concept peers showed no memory predilection. Although the low self-concept Black Ss also reflected no preference for their affective evaluations, the high self-concept Black Ss showed a greater propensity to recall their negatively rated words. Social class had a negligible effect on affective learning styles. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An examination of children's attributions and achievement-related evaluations in competitive, cooperative, and individualistic reward structures.

Studied how the reward structure of an achievement setting would affect children's attributions and evaluations of achievement outcomes. An achievement situation describing 2 children successfully and unsuccessfully performing a task in competitive, cooperative, and individualistic reward structures was presented to 400 children across 5 grade levels (1–5). Results show that different evaluative beliefs about the concepts of ability and reward allocation were associated with each reward contingency. Competitive and individualistic structures accentuated perceptions of individual differences and the value placed on achievement outcomes. Evaluations of cooperative vs competitive outcomes were dependent on the level of individual performance within the groups and the success of the cooperative group. (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Deposition,annealing and characterisation of high-dielectric-constant metal oxide films

Flims of metal oxides, such as Ta₂O₅, Nb₂O₅, Al₂O₃, HfO₂, ZrO₂ and TiO₂ have been fabricated by use of different precursor materials, deposition techniques and annealing techniques. Several analytical methods were applied to study the layers. New data of fundamental properties of these metal oxides are reported and related to practical features that are of importance in device design and manufacturing of advanced, highly integrated devices. This overview may facilitate the choice of an optimal combination of precursor material, deposition technique and corresponding annealing procedure for a specific application of these metal oxide films in microelectronics.