Poly(3,4-ethylenedioxythiophene) doped with poly(4-styrenesulfonate) (PEDOT/PSS) was synthesized by oxidative polymerization and pH dependence of structure and electrical conductivity of the cast films were investigated by means of UV-vis-NIR, XRD, AFM analyses, and four-point technique. It was found that the neutralization of PEDOT/PSS with NaOH decreased the absorption of bipolarons representing the PEDOT in the highly doped state and disrupted the π-π stacking of the PEDOT crystalline structure, which lowered the electrical conductivity by six orders of magnitude with increasing the pH from 1.7 to 13.

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The purpose of this report is to inform and warn academics about practices used by cybercriminals who seek to profit from unwary scholars and undermine the industry of science.This report describes the signs, symptoms, characteristics, and consequences of predatory publishing and related forms of consumer fraud. Methods to curb these cybercrimes include educating scholars and students about tactics used by predatory publishers; institutional changes in how faculty are evaluated using publications; soliciting cooperation from the industries that support academic publishing and indexing to curb incorporation of illegitimate journals; and taking an offensive position by reporting these consumer fraud crimes to the authorities. Over and above the problem of publishing good science in fraudulent journals, disseminating and citing poor-quality research threaten the credibility of science and of nursing.

Poly(3,4ethylenedioxythiophene) doped with poly(4styrenesulfonate) (PEDOT/PSS) with various PSS composition ratios (α) was synthesized by oxidative polymerization and particle size distribution and zeta potential of the resulting colloidal gel particles were investigated by means of a dynamic light scattering technique. It was found that mean volume diameter of the PEDOT/PSS colloidal gel particles were 400600 nm at α = 1~6, which drastically decreased to ~10 nm at α = 8~15. On the other hand, zeta potential was about 80 mV regardless of the composition ratio. The electrical conductivity of the PEDOT/PSS cast film measured by a fourpoint method attained as high as 263 S/cm at α = 3.

Atomically thin two-dimensional (2D) mechanical resonators should realize highly sensitive force sensors and high performance nano-electro-mechanical systems due to their excellent electrical and mechanical properties. However, practical applications require stability of the resonance frequencies against temperature. Here, we demonstrate the manipulation of the thermal expansion coefficients (TECs) by creating a van der Waals heterojunction using graphene and MoS2, which have opposite signs of TECs. Our method greatly suppresses the apparent TEC of the 2D heterojunction to 1/3 of the monolayer graphene without the detraction of the tunability of the resonance frequency by electrostatic attraction. 1

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