Intervention and revision: Expertise and interaction in text mediation

Many EAL (English as an Additional Language) scholars enlist text mediators’ support when faced with the challenges of writing for international publication. However, the contributions these individuals are able to make in improving scientific manuscripts remains unclear, especially when language professionals such as English teachers do this work. In this article, we explore this topic by examining how three mediators employed their very different expertise and brought different processes to bear on the same discussion section of a medical manuscript written by a novice scholar in China. We find that successfully mediated texts are often the result of an interplay between the mediator’s expertise and the relationship between the participants. Our findings contradict those of previous studies that question the role of English teachers in this process and have the potential to inform both text mediation practices and revision studies

Kompozycja elastomerowa z dodatkami wysoko zdyspergowanego węgla

The influence of a carbon nanomaterials (CNM) obtained in a high-voltage discharge plasma on the endurance of elastomer compositions has been investigated. Complex tests of elastomeric compositions with highly dispersed carbon additives allowed us to confirm the model of nonlinear elastic deformation of macromolecules and adhesion between the elastomer and the nanoparticles. The results of these investigations agree with those obtained in determining the Mooney viscosity and relaxation, the parameters of the vulcanization kinetics of rubber mix, conventional tensile strength, relative breaking elongation of highly filled rubbers based on nitrile rubbers. To verify the assumed mechanism underlying the action of a carbon nanomaterial on elastomer compositions, the parameters of their vulcanizing network have been determined using the method of equilibrium swelling.Badano wpływ nanomateriału węglowego uzyskanego w plazmie z wyładowań wysokiego napięcia na trwałość kompozycji elastomerowych. Kompleksowe testy kompozytów elastomerowych zawierających dodatki węgla o dużym stopniu zdyspergowania pozwoliły na potwierdzenie modelu nieliniowego odkształcenia sprężystego makrocząsteczek oraz adhezji między między elastomerem i nanocząstkami. Wyniki tych badań zgadzają się z uzyskanymi wynikami badania lepkości Mooneya oraz relaksacji, parametrami kinetyki wulkanizacji mieszanki kauczukowej, konwencjonalnej, wytrzymałości na rozciąganie, wydłużenia przy zerwaniu wysoko napełnionych wulkanizatów opartych na kauczukach butadienowo-nitrylowych. W celu sprawdzenia założonego mechanizmu leżącego u podstaw działania nanomateriału węglowego w kompozycjach elastomerowych, parametry ich sieci wulkanizacyjnych zostały określone metodą spęcznienia równowagowego

Characteristic properties of spinning solution and nanofibres from chitosan biopolymer

Electrospinning from solutions of polymers which is a promising way of nanofibres manufacture in the field of nanotechnologies is reviewed in the paper. Chitosan which possesses wound-healing action was used as polymer, it is also non-toxic, biocompatible and biodegradable. Nanofibres on its basis manifest the superdeveloped surface and voids rating. Taking into account wound he aling prope rties, chitosan is very effective at producing wound textile for burns, long nonhealing wounds, and trophic ulcers. Nanofibres from chitosan were produced according to the Nanospider technology on the NS LAB 500 S (ELMARCO, Czech Republic). During process of nanofibres electrospinning potential difference between electrodes up to 60 kV was created. Positively charged sprays push each other, move and vibrate during electrospinning. Diameter of a spray decreases towards nanosizes because their movement accelerates. The chemical composition, viscosity, and rheological parameters of the solution are developed. The electrospinning technology is optimized; the structure of a nanofiber layer is analyzed by method of scanning microscopy on JSM-5610 LV JEOL. Thus, the prospects of use of Nanospider technology are defined for production of nanofibres based on polymer solutions

Properties of model rubber compounds with different vulcanization activators

Influence of various vulcanization activators on properties of unfilled elastomeric compositions based on synthetic polyisoprene and oil-extended butadiene-styrene rubbers is investigated. Plastoelastic and relaxation properties, and also scorching resistance and kinetics of curing of rubber mixes with traditional and composite vulcanization activators are defined. As the composite vulcanization activator “Vulkativ-FC” was used. Its feature is the lowered content of zinc oxide and presence in the composition saturated fatty acids. The correlation of elastic and strength properties of vulcanizates with type and containing of the applied activator is established

Właściwości kompozycji elastomerowych z drobnymi dodatkami węglowymi poddanymi sonikacji

The influence of superfine carbon additives and their pretreatment by ultrasonication on the properties of elastomer compositions has been investigated. Superfine carbon additives come in two different types: fullerene-containing additives and ultra fine carbon additives (a complex mixture of nanofibers and nanotubes, graphite and amorphous carbon particles). Mooney viscosity, parameters of relaxation and vulcanization kinetics of rubber mixtures, tensile strength, elongation at break and resistance to thermal aging, abrasion resistance and compression of filled rubbers based on butadiene-acrylonitrile were carried out. Except for the identified characteristics, crosslink parameters by the method of equilibrium swelling were determined. It was found that the introduction of the ultrasonically pretreated, superfine carbon additives to elastomeric compositions based on butadiene-acrylonitrile rubber led to rubber with improved thermo-oxidative and wear resistance in comparison to rubbers containing untreated additives.Wykonano badania wpływu drobnych dodatków węglowych i ich wstępnej obróbki ultradźwiękami na właściwości kompozycji elastomerowych na bazie kauczuku butadienowo-akrylonitrylowego. Zastosowano dwa rodzaje drobnych dodatków węglowych: dodatek zawierający fulereny oraz wysoko zdyspergowany dodatek stanowiący mieszaninę złożoną z nanowłókien, nanorurek, grafitu oraz amorficznych cząstek węgla. Wyznaczono lepkość Mooney'a, parametry relaksacji i kinetykę wulkanizacji mieszanek gumowych, a metodą pęcznienia równowagowego określono gęstość usieciowania wulkanizatów. Zbadano także wytrzymałość na rozciąganie, odkształcenie przy zerwaniu, odporność na starzenie cieplne oraz odporność na ścieranie i ściskanie napełnionych gum