14 research outputs found
Europe’s perennial "outsiders": a processual approach to Roma stigmatization and ghettoization
This paper draws on the theoretical work of Norbert Elias and Loïc Wacquant in seeking to understand the stigmatized and marginalized position of the Roma population within Europe. The paper argues that the persistent persecution of Roma, reflected in social policy, cannot be understood without reference to long-term social processes, which shape the nature of the asymmetric power relations between Roma and non-Roma. Elias's theory of established-outsider relations is applied at the intra-state European level in arguing that Roma constitute a cross-border "outsider" group; with their intense stigmatization explained and perpetuated by a common set of collective fantasies which are maintained through complex group processes of disidentification, and which result in Roma being seen as of lesser human worth. Wacquant's theoretical concept of the "ghetto" is then drawn upon to show how the manifestations of stigmatization for the stigmatized are at once psychological, social and spatial. The paper suggests that the synthesis of the two theorists' relational, theoretical concepts allows for an approach that can expose the way in which power is exercised within and through group relations. Such an approach emphasizes the centrality of the interdependence between Roma and non-Roma, and the fluctuating power balance that characterises that relationship across time and space. The paper concludes that, while existing research focused on policy and outcomes is useful in understanding the negative contemporary experiences of Roma populations, they need to be understood in the context of wider social processes and historical continuities in seeking to elucidate how these processes shape policies and contribute to social and spatial marginalization
Top-gate hybrid complementary inverters using pentacene and amorphous InGaZnO thin-film transistors with high operational stability
© 2012 American Institute of Physics. The electronic version of this article is the complete one and can be found at: http://dx.doi.org/10.1063/1.3684635DOI: 10.1063/1.3684635We report on the operational stability of low-voltage hybrid organic-inorganic complementary
inverters with a top-gate bottom source-drain geometry. The inverters
are comprised of p-channel pentacene and n-channel amorphous InGaZnO thin-film
transistors (TFTs) with bi-layer gate dielectrics formed from an amorphous layer of
a fluoropolymer (CYTOP) and a high-k layer of Al₂O₃. The p- and n- channel TFTs
show saturationmobility values of 0.1±0.01 and 5.0±0.5 cm²/Vs, respectively. The
individual transistors show high electrical stability with less than 6% drain-to-source
current variations after 1 h direct current (DC) bias stress. Complementary inverters
yield hysteresis-free voltage transfer characteristics for forward and reverse input
biases with static DC gain values larger than 45 V/V at 8 V before and after being
subjected to different conditions of electrical stress. Small and reversible variations of
the switching threshold voltage of the inverters during these stress tests are compatible
with the observed stability of the individual TFTs
Molecular Engineering of Nonhalogenated Solution-Processable Bithiazole-Based Electron-Transport Polymeric Semiconductors
The electron deficiency and trans-planar
conformation of bithiazole
is potentially beneficial for the electron-transport performance of
organic semiconductors. However, the incorporation of bithiazole into
polymers through a facile synthetic strategy remains a challenge.
Herein, 2,2′-bithiazole was synthesized in one step and copolymerized
with dithienyldiketopyrrolopyrrole to afford poly(dithienyldiketopyrrolopyrrole-bithiazole), <b>PDBTz</b>. <b>PDBTz</b> exhibited electron mobility reaching
0.3 cm<sup>2</sup> V<sup>–1</sup> s<sup>–1</sup> in
organic field-effect transistor (OFET) configuration; this contrasts
with a recently discussed isoelectronic conjugated polymer comprising
an electron-rich bithiophene and dithienyldiketopyrrolopyrrole, which
displays merely hole-transport characteristics. This inversion of
charge-carrier transport characteristics confirms the significant
potential for bithiazole in the development of electron-transport
semiconducting materials. Branched 5-decylheptacyl side chains were
incorporated into <b>PDBTz</b> to enhance polymer solubility,
particularly in nonhalogenated, more environmentally compatible solvents. <b>PDBTz</b> cast from a range of nonhalogenated solvents exhibited
film morphologies and field-effect electron mobility similar to those
cast from halogenated solvents
Langmuir–Blodgett Thin Films of Diketopyrrolopyrrole-Based Amphiphiles
We
report on two π-conjugated donor–acceptor–donor
(D–A–D) molecules of amphiphilic nature, aiming to promote
intermolecular ordering and carrier mobility in organic electronic
devices. Diketopyrrolopyrrole was selected as the acceptor moiety
that was disubstituted with nonpolar and polar functional groups,
thereby providing the amphiphilic structures. This structural design
resulted in materials with a strong intermolecular order in the solid
state, which was confirmed by differential scanning calorimetry and
polarized optical microscopy. Langmuir–Blodgett (LB) films
of ordered mono- and multilayers were transferred onto glass and silicon
substrates, with layer quality, coverage, and intermolecular order
controlled by layer compression pressure on the LB trough. Organic
field-effect transistors and organic photovoltaics devices with active
layers consisting of the amphiphilic conjugated D–A–D-type
molecules were constructed to demonstrate that the LB technique is
an effective layer-by-layer deposition approach to fabricate self-assembled,
ordered thin films