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81.
We have fabricated organic thin-film transistors (OTFTs) based on di-n-decyldinaphtho[2,3-b:2′,3′-f]thieno[3,2-b]thiophene (C10-DNTT) on a polyimide gate dielectric coated on a polycarbonate substrate with a bottom-gate, top-contact configuration. Mobilities of the C10-DNTT-based TFTs were as high as 2.4 cm2 V?1 s?1, which are much better than those of the parent dinaphtho[2,3-b:2′,3′-f]thieno[3,2-b]thiophene (DNTT)-based TFTs (mobility ~ 0.5 cm2/V) fabricated on the same substrate. Compared to the C10-DNTT-TFTs on the conventional Si/SiO2 substrate, the present mobility of C10-DNTT-TFTs are somewhat reduced, which can be attributed to reduced crystallinity on the polyimide gate dielectric, although the crystalline phase on the polyimide is the same as on the Si/SiO2 substrate.  相似文献   
82.
<正>We propose a multi-symplectic wavelet splitting method to solve the strongly coupled nonlinear Schrodinger equations.Based on its multi-symplectic formulation,the strongly coupled nonlinear Schr(o|¨)dinger equations can be split into one linear multi-symplectic subsystem and one nonlinear infinite-dimensional Hamiltonian subsystem.For the linear subsystem,the multi-symplectic wavelet collocation method and the symplectic Buler method are employed in spatial and temporal discretization,respectively.For the nonlinear subsystem,the mid-point symplectic scheme is used.Numerical simulations show the effectiveness of the proposed method during long-time numerical calculation.  相似文献   
83.
The synthesis and functional analysis of KL001 derivatives, which are modulators of the mammalian circadian clock, are described. By using cutting‐edge C? H activation chemistry, a focused library of KL001 derivatives was rapidly constructed, which enabled the identification of the critical sites on KL001 derivatives that induce a rhythm‐changing activity along with the components that trigger opposite modes of action. The first period‐shortening molecules that target the cryptochrome (CRY) were thus discovered. Detailed studies on the effects of these compounds on CRY stability implicate the existence of an as yet undiscovered regulatory mechanism.  相似文献   
84.
A novel method for performing 2‐D map analysis is here reported, consisting in a modification of the second dimension run, which is performed not in a conventional square‐ or rectangular‐size gel, but in a radial surface. This has the advantage of permitting resolution of closely adjacent bands, representing strings of isoforms of similar or identical mass but of closely spaced isoelectric points. When used in a mono‐dimensional, SDS‐PAGE format, this system allows the simultaneous running of 62 sample tracks. Examples are given of separation of plasma and urinary proteins.  相似文献   
85.
C–S bond formation reactions are widely distributed in the biosynthesis of biologically active molecules, and thus have received much attention over the past decades. Herein, we report intramolecular C–S bond formation by a P450 monooxygenase, TleB, which normally catalyzes a C?N bond formation in teleocidin biosynthesis. Based on the proposed reaction mechanism of TleB, a thiol‐substituted substrate analogue was synthesized and tested in the enzyme reaction, which afforded the unprecedented sulfur‐containing thio‐indolactam V, in addition to an unusual indole‐fused 6/5/8‐tricyclic product whose structure was determined by the crystalline sponge method. Interestingly, conformational analysis revealed that the SOFA conformation is stable in thio‐indolactam V, in sharp contrast to the major TWIST form in indolactam V, resulting in differences in their biological activities.  相似文献   
86.
Fitting of the voltage vs. insertion curves of the LiFePO4 electrode was based on theoretical expressions describing the Li+ diffusive process in a solid medium. The noninteracting gas model for the chemical potential of ions distributed in a solid matrix was taken into account, and the diffusion coefficient and the energy activation for the diffusion process were accordingly calculated. The polarization curves at various discharge stages were theoretically obtained, and a good agreement was found with the experimental data at all discharge rates. A mathematical relation describing the trend of the diffusion resistance vs. insertion degree was also developed.  相似文献   
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Let (S,∪) be a finite join-semilattice and (D, ∨, ∧) be a distributive lattice. Let ?:S→D be a map satisfying ?(x ∪ y) ? ?(x) ∧ ?(y) for each x and y in S. Then for any valuation v on D the following identity holds.
v?xυS f(x)=cυC(?1)l(c)v?xυcf(x)
where C is the set of all chains in S and l(c) denotes the length of a chain c. Also the theorem can be dualized.  相似文献   
90.
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