Retention of Text Material under Cued and Uncued Recall and Open and Closed Book Conditions

Evidence supports the benefits of effortful processing in strengthening retention of newly learned material. The present study compared two forms of effortful processing, uncued (free) recall and cued recall, under both open and closed book conditions, on both immediate and delayed (one-week) test performance. Participants read a section of a child psychology text and then completed either an uncued recall task in which they typed as much information as they could recall, or a cued recall task, in which they typed answers to study questions. Recall was conducted under open versus closed book conditions. No differences between cued and uncued conditions were obtained, but participants performed better on immediate test performance in the open book condition. No significant effects were found at delayed assessment. The results point to a short-term advantage of effortful review of text materials performed with access to study materials

Retention of Text Material under Cued and Uncued Recall and Open and Closed Book Conditions

Evidence supports the benefits of effortful processing in strengthening retention of newly learned material. The present study compared two forms of effortful processing, uncued (free) recall and cued recall, under both open and closed book conditions, on both immediate and delayed (one-week) test performance. Participants read a section of a child psychology text and then completed either an uncued recall task in which they typed as much information as they could recall, or a cued recall task, in which they typed answers to study questions. Recall was conducted under open versus closed book conditions. No differences between cued and uncued conditions were obtained, but participants performed better on immediate test performance in the open book condition. No significant effects were found at delayed assessment. The results point to a short-term advantage of effortful review of text materials performed with access to study materials

Modular synthesis of functional polymer nanoparticles from a versatile platform based on poly(pentafluorophenylmethacrylate)

Control of functionalities in polymer nanoparticles (PNPs) is important for their application. Thus, there is an interest for well-defined nanoparticle platforms to which desired functions could readily, and in modular fashion, be imparted. Herein, we report an amine-reactive PNP platform for the modular synthesis of functional PNPs from poly(pentafluorophenylmethacrylate) (poly(PFPMA)) through a simple substitution/nanoprecipitation/photo-crosslinking strategy. Substitution of amine containing coumarin into poly(PFPMA) allows for the achievement of structural stability of nanoprecipitated particles through photo-crosslinking after nanoprecipitation, making it possible to carry out subsequent chemical transformations in organic solvents if needed. We demonstrate that various small molecules and an amine-terminated polymer could be used to modify the crosslinked PNPs to endow them with various functions including fluorescence and responsiveness to temperature changes. The functional PNPs were characterized with variable temperature dynamic light scattering (DLS), UV-vis, and photoluminescence (PL) spectroscopy, and transmission electron microscopy (TEM). (C) 2016 Wiley Periodicals, Inc.N

Recent advances in the polymerization of elemental sulphur, inverse vulcanization and methods to obtain functional Chalcogenide Hybrid Inorganic/Organic Polymers (CHIPs)

Recent developments in the polymerization of elemental sulfur and the preparation of functional Chalcogenide Hybrid Inorganic/Organic Polymers (CHIPs) are reviewed. CHIPs represent a class of polymers synthesized from elemental sulfur with the incorporation of inorganic chalcogenide components (S, Se, Te) into the organic polymeric backbones. Novel CHIP materials exhibit interesting optical, electrochemical and mechanical properties that lead to applications in thermal imaging, energy storage, self-healable materials and separation science. The emphasis of this review is on the key advances in the synthetic approaches to prepare functional polymeric sulfur-rich materials, with recent developments in synthesis, characterization, and application milestones being highlighted.N

Rational design of sulfur-containing composites for high-performance lithium-sulfur batteries

Sulfur has received considerable attention as a cathode material for lithium-sulfur (Li-S) batteries due to its high theoretical energy density (2567 W h kg(-1)), high earth abundance, and environmental benignity. However, the insulating nature of sulfur and the shuttle effect of soluble lithium polysulfides result in serious technical issues, such as low utilization rate of sulfur, reduced columbic efficiency, and poor cycling stability, which compromise the high theoretical performance of Li-S batteries. In the past years, various attempts have been made to achieve high specific capacity and reliable cycling stability of Li-S batteries. Incorporation of sulfur into functional host materials has been demonstrated to be effective to improve the electrochemical performance of sulfur-based cathodes via enhancing the electron and Li ion conductivities, immobilizing sulfur/lithium polysulfides in cathodes, and accommodating the volume changes in sulfur-based cathodes. Therefore, the rational design of sulfur-containing composites needs to be emphasized as key strategies to develop high-performance cathodes for Li-S batteries. In this perspective, after reviewing the achievements obtained in the design of sulfur-containing composites as cathodes for Li-S batteries, we propose the new issues that should be overcome to facilitate the practical application of Li-S batteries.

Polymerizations with elemental sulfur: A novel route to high sulfur content polymers for sustainability, energy and defense

Recent developments in the polymerizations of elemental sulfur (S-8) to prepare high sulfur content polymers are reviewed. While the homopolymerization of S-8 via ring-opening processes to prepare high molar mass polymeric sulfur has long been known, this form of polymeric sulfur is chemically unstable and depolymerizes back to S-8. In the current report, we discuss the background into the production of sulfur via petroleum refining and the challenges associated with utilizing S-8 as a chemical reagent for materials synthesis. To circumvent these long standing challenges in working with sulfur, the use of S-8 as a reaction medium and comonomer in a process termed, inverse vulcanization, was developed to prepare chemically stable and processable sulfur copolymers. Furthermore, access to polymeric materials with a very high content of sulfur-sulfur (S-S) bonds enabled for the first time the creation of materials with useful (electro)chemical and optical properties which are reviewed for use in Li-S batteries, IR imaging technology and self-healing materials. (C) 2016 Published by Elsevier Ltd.N