Wholly Aromatic Ether-Imides as n-Type Semiconductors

Some wholly aromatic ether-imides consisting of rod-shaped, relatively-low-mass molecules that can form liquid crystals have been investigated for potential utility as electron-donor-type (ntype) organic semiconductors. It is envisioned that after further research to improve understanding of their physical and chemical properties, compounds of this type would be used to make thin film semiconductor devices (e.g., photovoltaic cells and field-effect transistors) on flexible electronic-circuit substrates. This investigation was inspired by several prior developments: Poly(ether-imides) [PEIs] are a class of engineering plastics that have been used extensively in the form of films in a variety of electronic applications, including insulating layers, circuit boards, and low-permittivity coatings. Wholly aromatic PEIs containing naphthalene and perylene moieties have been shown to be useful as electrochromic polymers. More recently, low-molecular-weight imides comprising naphthalene-based molecules with terminal fluorinated tails were shown to be useful as n-type organic semiconductors in such devices as field-effect transistors and Schottky diodes. Poly(etherimide)s as structural resins have been extensively investigated at NASA Langley Research Center for over 30 years. More recently, the need for multi-functional materials has become increasingly important. This n-type semiconductor illustrates the scope of current work towards new families of PEIs that not only can be used as structural resins for carbon-fiber reinforced composites, but also can function as sensors. Such a multi-functional material would permit so-called in-situ health monitoring of composite structures during service. The work presented here demonstrates that parts of the PEI backbone can be used as an n-type semiconductor with such materials being sensitive to damage, temperature, stress, and pressure. In the near future, multi-functional or "smart" composite structures are envisioned to be able to communicate such important parameters to the flight crew and provide vital information with respect to the operational status of their aircraft

Randomised phase 3 study of adjuvant chemotherapy with or without nadroparin in patients with completely resected non-small-cell lung cancer: the NVALT-8 study

Contains fulltext : 207334.pdf (publisher's version ) (Open Access

New generation hole transporting materials for perovskite solar cells: amide-based small-molecules with nonconjugated backbones

State‐of‐the‐art perovskite‐based solar cells employ expensive, organic hole transporting materials (HTMs) such as Spiro‐OMeTAD that, in turn, limits the commercialization of this promising technology. Herein an HTM (EDOT‐Amide‐TPA) is reported in which a functional amide‐based backbone is introduced, which allows this material to be synthesized in a simple condensation reaction with an estimated cost of <$5 g−1. When employed in perovskite solar cells, EDOT‐Amide‐TPA demonstrates stabilized power conversion efficiencies up to 20.0% and reproducibly outperforms Spiro‐OMeTAD in direct comparisons. Time resolved microwave conductivity measurements indicate that the observed improvement originates from a faster hole injection rate from the perovskite to EDOT‐Amide‐TPA. Additionally, the devices exhibit an improved lifetime, which is assigned to the coordination of the amide bond to the Li‐additive, offering a novel strategy to hamper the migration of additives. It is shown that, despite the lack of a conjugated backbone, the amide‐based HTM can outperform state‐of‐the‐art HTMs at a fraction of the cost, thereby providing a novel set of design strategies to develop new, low‐cost HTMs

New generation hole transporting materials for perovskite solar cells: amide-based small-molecules with nonconjugated backbones

State‐of‐the‐art perovskite‐based solar cells employ expensive, organic hole transporting materials (HTMs) such as Spiro‐OMeTAD that, in turn, limits the commercialization of this promising technology. Herein an HTM (EDOT‐Amide‐TPA) is reported in which a functional amide‐based backbone is introduced, which allows this material to be synthesized in a simple condensation reaction with an estimated cost of <$5 g−1. When employed in perovskite solar cells, EDOT‐Amide‐TPA demonstrates stabilized power conversion efficiencies up to 20.0% and reproducibly outperforms Spiro‐OMeTAD in direct comparisons. Time resolved microwave conductivity measurements indicate that the observed improvement originates from a faster hole injection rate from the perovskite to EDOT‐Amide‐TPA. Additionally, the devices exhibit an improved lifetime, which is assigned to the coordination of the amide bond to the Li‐additive, offering a novel strategy to hamper the migration of additives. It is shown that, despite the lack of a conjugated backbone, the amide‐based HTM can outperform state‐of‐the‐art HTMs at a fraction of the cost, thereby providing a novel set of design strategies to develop new, low‐cost HTMs

Schizophrenia in Thailand: prevalence and burden of disease

Background: A previous estimate of the burden of schizophrenia in Thailand relied on epidemiological estimates from elsewhere. The aim of this study is to estimate the prevalence and disease burden of schizophrenia in Thailand using local data sources that recently have become available

Randomised phase 3 study of adjuvant chemotherapy with or without nadroparin in patients with completely resected non-small-cell lung cancer:the NVALT-8 study

Background: Retrospective studies suggest that low molecular weight heparin may delay the development of metastasis in patients with resected NSCLC. Methods: Multicentre phase 3 study with patients with completely resected NSCLC who were randomised after surgery to receive chemotherapy with or without nadroparin. The main exclusion criteria were R1/2 and wedge/segmental resection. FDG-PET was required. The primary endpoint was recurrence-free survival (RFS). Results: Among 235 registered patients, 202 were randomised (nadroparin: n = 100; control n = 102). Slow accrual enabled a decrease in the number of patients needed from 600 to 202, providing 80% power to compare RFS with 94 events (α = 0.05; 2-sided). There were no differences in bleeding events between the two groups. The median RFS was 65.2 months (95% CI, 36—NA) in the nadroparin arm and 37.7 months (95% CI, 22.7—NA) in the control arm (HR 0.77 (95% CI, 0.53–1.13, P = 0.19). FDG-PET SUVmax ≥10 predicted a greater likelihood of recurrence in the first year (HR 0.48, 95% CI 0.22–0.9, P = 0.05). Conclusions: Adjuvant nadroparin did not improve RFS in patients with resected NSCLC. In this study, a high SUVmax predicted a greater likelihood of recurrence in the first year. Clinical trial registration: Netherlands Trial registry: NTR1250/1217

The role of ortho-, meta- and para-substitutions in the main-chain structure of poly(etherimide)s and the effects on CO2/CH4 gas separation performance

A homologous series of 12 all-aromatic PEI membranes was investigated with the aim to understand how subtle changes in the PEI main-chain affect the carbon dioxide/methane (CO2/CH4) gas separation performance. The 3-ring diamines selected for this study are either para-, meta- or ortho-aryloxy substituted with respect to the central benzene ring, i.e. 1,4-bis(4-aminophenoxy)benzene (P1), 1,3-bis(4-aminophenoxy)benzene (M1) and 1,2-bis(4-aminophenoxy)benzene (O1). Doing so changes the backbone geometry from a more linear to a more kinked conformation. In addition, four dianhydrides were selected with the aim to tailor the segmental mobility and hence the free volume of the PEIs, i.e. pyromellitic dianhydride (PMDA), 3,3′,4,4′-biphenyltetracarboxylic dianhydride (BPDA), 3,3′,4,4′-benzophenonetetracarboxylic dianhydride (BTDA) and 3,3′,4,4′-oxydiphthalic dianhydride (ODPA). We have investigated how subtle changes in these prototypical PEIs affect membrane critical performance criteria such as CO2 permeability, CO2/CH4 selectivity and ability to withstand high operating pressures. In ODPA-based membranes the CO2 permeability decreases in the order P1 > O1 > M1 and remains steady throughout measurements with mixed feed pressures up to 40 bar, however, the selectivity decreases for ODPA-O1 and ODPA-M1. For high-pressure applications, the OPDA-P1 membrane is a good candidate with a selectivity of 48, permeability of CO2 of 0.74 Barrer and ability to resist plasticization up to 40 bar of total pressure (16 bar of CO2 partial pressure). Alternatively, for applications up to 10 bar of total mixed feed (5 bar of CO2 partial pressure), BPDA-O1 is a promising candidate because this membrane displays a high selectivity of 70 and permeability of 1.3 Barrer