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141.
Hisaaki Tanaka Shinya Kawamura Prashant Sonar Yukihiro Shimoi Thu Trang Do Taishi Takenobu 《Advanced functional materials》2020,30(25)
Elucidating the interrelation between the molecular structure and charge transport properties in conjugated polymer thin films is an essential issue in developing the design principle of high‐performance polymer materials for application in organic electronics. In particular, the backbone planarity is suggested to be a key element that governs the transport performance, especially in recently developed donor–acceptor (D–A)‐type copolymers exhibiting high mobility, whereas the direct evaluation of the intrinsic transport performance, usually realized only within the small crystalline domains, is difficult by using conventional macroscopic measurements. Here, it is demonstrated that a D–A type copolymer, PDPPF‐DTT, which consists of furan‐flanked diketopyrrolopyrrole (DPP) and dithienothiophene (DTT) units in the conjugated backbone, exhibits a highly efficient charge transport performance within the crystalline domains with a remarkably low activation energy of less than 8 meV, based on microscopic measurements using field‐induced electron spin resonance spectroscopy. This high transport performance is primarily caused by the high backbone planarity realized by introducing furan‐flanked DPP and fused dithienothiophene units, which is demonstrated from the density functional theory calculations. This result provides a microscopic indication of the effectiveness of the present molecular design to produce a planar backbone and realize highly efficient charge transport performance. 相似文献
142.
[reaction: see text] If employed in THF at 0 degrees C, LTMP metalates meta-anisic acid at the doubly activated position. In contrast, n-BuLi/t-BuOK deprotonates position C-4 preferentially at low temperature. Functionalization at C-6 requires protection of the C-2 site beforehand. As a result of these findings, a new mechanism is proposed for the heteroatom-directed ortholithiation of aromatic compounds. 相似文献
143.
Hung Huynh Aldo Prawira Thi Bich Uyen Le Thanh Chung Vu Huai-Xiang Hao Alan Huang Youzhen Wang Diana Graus Porta 《Experimental & molecular medicine》2020,52(11):1857
Hepatocellular carcinoma (HCC) is a lethal cancer with limited therapeutic options, and standard therapy with sorafenib provides only modest survival benefits. Fibroblast growth factor 19 (FGF19) has been proposed as a driver oncogene, and targeting its receptor, FGFR-4, may provide a better alternative to standard therapy for patients with FGF19-driven tumors. Sixty-three HCC patient-derived xenograft (PDX) models were screened for FGF19 expression. Mice bearing high and low FGF19-expressing tumors were treated with FGF401 and/or vinorelbine, and the antitumor activity of both agents was assessed individually and in combination. Tumor vasculature and intratumoral hypoxia were also examined. High FGF19 expression was detected in 14.3% (9 of 63) of the HCC models tested and may represent a good target for HCC treatment. FGF401 potently inhibited the growth of high FGF19-expressing HCC models regardless of FGF19 gene amplification. Furthermore, FGF401 inhibited the FGF19/FGFR-4 signaling pathway, cell proliferation, and hypoxia, induced apoptosis and blood vessel normalization and prolonged the overall survival (OS) of mice bearing high FGF19 tumors. FGF401 synergistically acted with the microtubule-depolymerizing drug vinorelbine to further suppress tumor growth, promote apoptosis, and prolong the OS of mice bearing high FGF19 tumors, with no evidence of increased toxicity. Our study suggests that a subset of patients with high FGF19-expressing HCC tumors could benefit from FGF401 or FGF401/vinorelbine treatment. A high level of FGF19 in a tumor may serve as a potential biomarker for patient selection.Subject terms: Cancer models, Targeted therapies 相似文献
144.
Solar Cells: Rationally Designed Donor–Acceptor Random Copolymers with Optimized Complementary Light Absorption for Highly Efficient All‐Polymer Solar Cells (Adv. Funct. Mater. 38/2017) 下载免费PDF全文
145.
The emission spectra of thermally stimulated surface plasmon polaritons (thermally stimulated surface plasmon polaritons) and a blackbody have been analyzed and compared, and the temperature dependence of these spectra has been studied. It has been found that the total energy of the entire ensemble of surface plasmons is proportional to the cube of temperature and their spectrum is red-shifted from the blackbody spectrum. It has been shown that the spectrum of thermally stimulated surface plasmon polaritons obeys the Wien’s displacement law, yet with another constant. The fraction of the photon energy of the conducting layer transferred to the surface plasmons has been estimated. It has been demonstrated numerically by the example of a gold layer that this fraction can exceed 10% for a layer thickness of less than 1 mm. 相似文献
146.
Nam Trang 《Israel Journal of Mathematics》2016,215(2):607-667
This paper explores the consistency strength of The Proper Forcing Axiom (PFA) and the theory (T) which involves a variation of the Viale–Weiβ guessing hull principle. We show that (T) is consistent relative to a supercompact cardinal. The main result of the paper is Theorem 0.2, which implies that the theory “ADR + ? is regular” is consistent relative to (T) and to PFA. This improves significantly the previous known best lower-bound for consistency strength for (T) and PFA, which is roughly “ADR + DC”. 相似文献
147.
Structural Chemistry - The antioxidative activity of natural product compound amurensin H (1) and its three synthetic compounds 5-(6-hydroxy-2-(4-hydroxyphenyl)benzofuran-3-yl)benzene-1,3-diol (2),... 相似文献
148.
V. V. Gerasimov A. K. Nikitin I. Sh. Khasanov Ta Thu Trang 《Optics and Spectroscopy》2017,123(6):893-902
An analytical model of the spectrum of thermally stimulated surface plasmon polaritons (TSSPPs) coming to the edge of a linear conducting sample has been developed. It has been found that the spectrum of such TSSPPs obeys neither the Wien law nor the Stefan–Boltzmann law for thermal radiation. The maximum of this spectrum is shifted to the low-frequency region with respect to the spectrum of the absolutely black body, and the magnitude of the shift is proportional to the sample length. The plasmon nature of the intensity increment of thermal radiation from the edge of a plane face of a duralumin sample has been verified experimentally. It has been shown that the intensity and spectrum of this increment can be controlled both by the sample temperature and by the extension of the face. 相似文献
149.
Regioselective deuteration of 1-X-C2B10H12 (X = 2, 7) cage systems with C6D6/AlCl3 is correlated to ab initio calculational results on a [C2B10H13]+ intermediate. Full geometry optimizations of pertinent [C2B10H13]+ isomers, derived from each of the two 1-X-C2B10H12 carborane isomers, result in cage geometries not unlike the (nearly) icosahedral starting carborane. Each isomer contains a BH2 group having an acute H-B-H angle, long B–H bonds, and a very short H · · · H distance, hinting that the pertinent boron shares the electrons of a hydrogen molecule σ pair. It is suggested that the structural differences between the BH2 group of [C2B10H13]+ and the CH2 group of the benzenium ion, [C6H7]+ (the intermediate strongly intimated upon protonation of benzene), can be explained, in part, by (a) the availability of the π-ring electrons for bonding to the (extra) proton in the latter and (b) the unavailability of π electrons from the carborane. Thus, the C2B10H12 cage is most probably very reluctant to give up a cage electron pair in order to assist in bonding to an (externally bound) proton. Instead, it is more probable that “hydridic” B–H sigma electrons could very well play the important role in providing bonding to the attacking proton. © 1998 John Wiley & Sons, Inc. Heteroatom Chem 9:95–102, 1998 相似文献
150.
Thanh N. Truong Uyen N. Nguyen Eugene V. Stefanovich 《International journal of quantum chemistry》1996,60(7):1615-1622
We present an assessment on the accuracy of a dielectric continuum solvation model, the generalized conductor-like screening model (GCOSMO), for predicting hydration free energies, tautomeric equilibria, and reaction profiles in solution. © 1996 John Wiley & Sons, Inc. 相似文献