For centuries, there have been discussions as to whether only experts can judge the quality of cultural output, or whether the taste of the public also has merit. This paper tries to answer that question empirically, using national finals of the Eurovision Song Contest. We show that experts are better judges of quality in the sense that the outcome of finals judged by experts is less sensitive to factors unrelated to quality than the outcome of finals judged by public opinion. Yet, experts are not perfect; their judgment does still depend on such factors. This is also the case in the European finals of the contest.
This article uses factor analysis to identify the underlying dimensions of strategic and structural entry barriers. We find that, in the perception of firms, both types of barriers are important and that the effectiveness of strategic barriers depends on attributes of the market structure. Based on the seven generic factors, a conjoint analysis is carried out to identify the most important factors perceived by firms. The conjoint analysis shows that in particular the barriers rooted in three underlying dimensions require attention of market authorities as they may prevent new entrants from entry: capital, access to distribution channels and strategic action. Remarkably, government rules and regulations, product differentiation, research and development (R&D) and advertising constitute minor entry problems according to firms.
This paper describes the effectiveness of donor− acceptor (D-A) conjugated polymers to disperse and select for semiconducting single-walled carbon nanotubes (s-SWCNTs) when enhanced by the inclusion of polar oligoethylene glycolbased side chains, without altering the D−A backbone. We designed and synthesized two sets of naphthalenediimide(NDI)alt-bithiophene(T2)-based conjugated polymers with one of two alkyl side chains (decyl and dodecyl chains) of different lengths and with or without polar triethylene glycol side chains. The resulting low-band-gap copolymers all effectively disperse and select for s-SWCNT, but the inclusion of polar side chains enhances the interactions between the polymer backbone and the walls of the s-SWCNTs relative to the polymers with only alkyl side chains. As a result, the wrapping and selection efficiency of the polymer-SWCNT systems with polar side chains are both significantly enhanced. We further optimized the binding energy and surface coverage by combining glycol ether and dodecyl side chains to maximize wrapping efficiency, leading to a field-effect mobility of 2.82 cm 2 V −1 s −1 and on/off current ratios of ∼2 × 10 7 in polymer-wrapped SWCNTs. Our results provide insight into the role of the side-chain interactions in the polymer wrapping and dispersion technique, and, because we focus on manipulating side chains, they can be generalized for other conjugated polymer backbones.
The objective of this paper is to analyse the relationship between perceived entry barriers and real entry. Real entry rates are interpreted as an indicator for the dynamics in an industry. The major hypothesis of this paper is that important entry barriers restrict new entry. Real entry rates are provided by a starter ratio for different industrial sectors and provinces in the Netherlands. Firms were interviewed in December 2004 to obtain data about the perceived importance of a large number of entry barriers (structural as well as strategic). The most important barriers, perceived by firms, are related to acquiring sufficient sales volume and capital, financial risks, cost disadvantages, cost of capital, economies of scale and product differentiation. The data on perceived entry barriers and information about the attractiveness of the market, are used to explain real entry in the first six months of 2005. Generally, the results confirm the expected relationship between entry barriers and real entry. However, some barriers seem to influence the starter ratio more strongly. Remarkably, several of the most 'important' perceived barriers do not restrict real entry rates. This result contains an interesting lesson for policy makers. They should not address important barriers per se, but scrutinize the effects of barriers that seem to restrict real entry. For example, government regulations are not perceived as one of the most important entry barriers. Nevertheless, this barrier has a strong impact on starter ratios. This result justifies why the Dutch government scrutinizes the relevance of existing rules and regulations.
Conjugated polymers with narrow band gaps are particularly useful for sorting and discriminating semiconducting single-walled carbon nanotubes (s-SWCNT) due to the low charge carrier injection barrier for transport. In this paper, we report two newly synthesized narrow-band-gap conjugated polymers (PNDITEG-TVT and PNDIC8TEG-TVT) based on naphthalene diimide (NDI) and thienylennevinylene (TVT) building blocks, decorated with different polar side chains that can be used for dispersing and discriminating s-SWCNT. Compared with the mid-band-gap conjugated polymer PNDITEG-AH, which is composed of naphthalene diimide (NDI) and head-to-head bithiophene building blocks, the addition of a vinylene linker eliminates the steric congestion present in head-to-head bithiophene, which promotes backbone planarity, extending the π-conjugation length and narrowing the band gap. Cyclic voltammetry (CV) and density functional theory (DFT) calculations suggest that inserting a vinylene group in a head-to-head bithiophene efficiently lifts the highest occupied molecular orbital (HOMO) level (−5.60 eV for PNDITEG-AH, −5.02 eV for PNDITEG-TVT, and −5.09 eV for PNDIC8TEG-TVT). All three polymers are able to select for s-SWCNT, as evidenced by the sharp transitions in the absorption spectra. Field-effect transistors (FETs) fabricated with the polymer:SWCNT inks display p-dominant properties, with higher hole mobilities when using the NDI-TVT polymers as compared with PNDITEG-AH (0.6 cm2 V–1 s–1 for HiPCO:PNDITEG-AH, 1.5 cm2 V–1 s–1 for HiPCO:PNDITEG-TVT, and 2.3 cm2 V–1 s–1 for HiPCO:PNDIC8TEG-TVT). This improvement is due to the better alignment of the HOMO level of PNDITEG-TVT and PNDIC8TEG-TVT with that of the dominant SWCNT specie.
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