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101.
Two polymers containing(E)-2,3-bis(thiophen-2-yl)acrylonitrile(CNTVT) as a donor unit, perylene diimide(PDI) or naphthalene diimide(NDI) as an acceptor unit, are synthesized by the Stille coupling copolymerization, and used as the electron acceptors in the solution-processed organic solar cells(OSCs). Both polymers exhibit broad absorption in the region of 300–850 nm. The LUMO energy levels of the resulted polymers are ca. –3.93 eV and the HOMO energy levels are –5.97 and –5.83 eV. In the binary blend OSCs with PTB7-Th as a donor, PDI polymer yields the power conversion efficiency(PCE) of up to 1.74%, while NDI polymer yields PCE of up to 3.80%. 相似文献
102.
Qun Yang Hui Ma Zhengwei Dai Jinfeng Wang Shaowei Dong Jiajia Shen Jun Dong 《Cellulose (London, England)》2017,24(9):3777-3787
Composite films comprised of bacterial cellulose (BC) and collagen (COL) were developed using BC hydrogel membranes as the base material and COL as the reinforcing material. Glutaraldehyde (GT) and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC·HCl) were then used as cross-linking agents to prepare cross-linked BC/COL composite films by a wet chemical method. The effects of chemical cross-linking on the thermal and mechanical properties of composite films were investigated in detail. The COL molecules were adsorbed and deposited inside of 3D nanofiber networks of BC, coated on the surface of BC fibers. Chemical bonds formed between BC molecules, and between BC and COL molecules after cross-linking. Compared with BC, the obtained composite films showed 57.9 and 70.8% improvement in tensile strength after being cross-linked by GT and EDC·HCl, respectively. Cross-linking also enhanced the thermal stability of the specimens. 相似文献
103.
In this paper, let α be any real number between 0 and 2, we study the Dirichlet problem for semi-linear elliptic system involving the fractional Laplacian: We will first establish the equivalence between PDE problem (1) and the corresponding integral equation (IE) system (Lemma 2). Then we use the moving planes method in integral forms to establish our main theorem, a Liouville type theorem for the integral system (Theorem 3). Then we conclude the Liouville type theorem for the above differential system involving the fractional Laplacian (Corollary 4).
相似文献
$$\left \{\begin {array}{l} (-{\Delta })^{\alpha /2}u(x)=v^{q}(x),\ \ \ x\in \mathbb {R}^{n}_{+},\\ (-{\Delta })^{\alpha /2}v(x)=u^{p}(x),\ \ \ x\in \mathbb {R}^{n}_{+},\\ u(x)=v(x)=0,\ \ \ \ \ \ \ \ \ \ x\notin \mathbb {R}^{n}_{+}. \end {array}\right .\label {elliptic} $$
(1)
104.
A novel tandem one-pot method for the synthesis of polysubstituted pyridine derivatives has been developed via Knoevenagel-type reaction and subsequent 6π electrocyclization of the Blaise reaction intermediates and 3-formylchromones. Short reaction time, moderate to good yields and excellent functional group tolerance have been accomplished in this protocol. 相似文献
105.
A ferrocene-derived P,N-heterodonor ligand was effectively used in a Cu(OAc)2·H2O-catalysed asymmetric 1,3-dipolar cycloaddition of azomethine ylides with maleate derivatives, affording cycloadducts with high yields (up to 96%), diastereoselectivities (>99 dr), and enantioselectivities (up to 99% ee). 相似文献
106.
Xuchu Wang Weiwei Liu Binbin Yin Yiwen Sang Zhenping Liu Yu Dai Xiuzhi Duan Gong Zhang Shijia Ding Zhihua Tao 《Mikrochimica acta》2017,184(6):1603-1610
The authors describe a method for DNA target recognition and signal amplification that is based on the target-induced formation of a three way junction. The subsequent assembly of two DNA probes releases the inhibitory strand and triggers a downstream strand displacement amplification. This causes the formation of a G-rich single sequence that binds to a hemin monomer with its peroxidase-mimicking properties. The resulting peroxidase (POx) activity is quantified by using H2O2 and TMB as the substrate. In the presence of an inhibitor, in contrast, the POx-like activity is strongly reduced. This forms the basis for a highly sensitive DNA assay. It has a 0.8 pM detection limit when operated at a wavelength of 450 nm and was applied to the isothermal determination of target DNA with high selectivity. 相似文献
107.
We generalize an important theorem of Fred Galvin from the Stone-Cˇech compactification βT of any discrete semigroup T to any compact Hausdorff right-topological semigroup with a dense topological center;and then apply it to Ellis' semigroups to prove that a point is distal if and only if it is IP*-recurrent, for any semiflow(T, X) with arbitrary compact Hausdorff phase space X not necessarily metrizable and with arbitrary phase semigroup T not necessarily cancelable. 相似文献
108.
A New kHz Velocity Map Ion/Electron Imaging Spectrometer for Femtosecond Time-Resolved Molecular Reaction Dynamics Studies 下载免费PDF全文
Zhi-gang He Zhi-chao Chen Dong-yuan Yang Dong-xu Dai Guo-rong Wu Xue-ming Yang 《化学物理学报(中文版)》2017,30(3):247-252
A new velocity map imaging spectrometer is constructed for molecular reaction dynamics studies using time-resolved photoelectron/ion spectroscopy method.By combining a kHz pulsed valve and an ICCD camera,this velocity map imaging spectrometer can be run at a repetition rate of 1 kHz,totally compatible with the fs Ti:Sapphire laser system,facilitating time-resolved studies in gas phase which are usually time-consuming.Time-resolved velocity map imaging study of NH3 photodissociation at 200 nm was performed and the time-resolved total kinetic energy release spectrum of H+NH2 products provides rich information about the dissociation dynamics of NH3.These results show that this new apparatus is a powerful tool for investigating the molecular reaction dynamics using time-resolved methods. 相似文献
109.
Zhang Ya Zhou Zhifeng Wen Fangfang Yuan Kechun Tan Jin Zhang Zilan Wang Honggui 《Journal of Solid State Electrochemistry》2017,21(12):3649-3657
Journal of Solid State Electrochemistry - Bacterial cellulose (BC) is a polysaccharide with tubular structure and can be produced by various species of bacteria particularly Acetobacter xylinum. It... 相似文献
110.
Using the equivalent block two-by-two real linear systems and relaxing technique, we establish a new block preconditioner for a class of complex symmetric indefinite linear systems. The new preconditioner is much closer to the original block two-by-two coefficient matrix than the Hermitian and skew-Hermitian splitting (HSS) preconditioner. We analyze the spectral properties of the new preconditioned matrix, discuss the eigenvalue distribution and derive an upper bound for the degree of its minimal polynomial. Finally, some numerical examples are provided to show the effectiveness and robustness of our proposed preconditioner. 相似文献