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1.
Guo-Xing Li Xiao-Wei Qu Lu-Wei Hao Qing Li Su Chen 《Journal of polymer science. Part A, Polymer chemistry》2022,60(11):1710-1717
From the implementation point of view, the printable magnetic Janus colloidal photonic crystals (CPCs) microspheres are highly desirable. Herein, we developed a dispensing-printing strategy for magnetic Janus CPCs display via a microfluidics-automatic printing system. Monodisperse core/shell colloidal particles and magnetic Fe3O4 nanoparticles precursor serve as inks. Based on the equilibrium of three-phase interfacial tensions, Janus structure is successfully formed, followed by UV irradiation and self-assembly of colloid particle to generate magnetic Janus CPCs microspheres. Notably, this method shows distinct superiority with highly uniform Janus CPCs structure, where the TMPTA/Fe3O4 hemisphere is in the bottom side while CPCs hemisphere is in the top side. Thus, by using Janus CPCs microspheres with two different structural colors as pixel points, a pattern with red flower and green leaf is achieved. Moreover, 1D linear Janus CPCs pattern encapsulated by hydrogel is also fabricated. Both the color and the shape can be changed under the traction of magnets, showing great potentials in flexible smart displays. We believe this work not only offers a new feasible pathway to construct magnetic Janus CPCs patterns by a dispensing-printable fashion, but also provides new opportunities for flexible and smart displays. 相似文献
2.
Yunjie Xiang Suoping Peng Shaohui Zheng 《International journal of quantum chemistry》2020,120(1):e26047
Organic solar cell of silol dithiophene based D2-A-D1-A-D2/PC71BM (D: donor part; A: acceptor part; 1 and 2 denote different units) possesses promising power conversion efficiency. Researchers have studied D2-A-D1-A-D2 molecules carefully, including the effects of the different number of terminal thiophenes, the different central moiety (D1), and the length of the alkyl chain. However, there are few investigations, especially theoretical studies, on the influences of different A (acceptor) units on the properties of D2-A-D1-A-D2 molecule. In the present work, we have designed and modeled five new D2-A-D1-A-D2 (D2 = bithiophene and D1 = silol dithiophene) donors by changing A units (A = diketopyrrolopyrrole, naphtho[1,2-c:5,6-c′]bis[1,2,5]thiadiazole, 5-fluoro-2,1,3-benzoselenadiazole, benzobisthiadiazole, and thiazolo[5,4-d]thiazole). We have applied density functional theory (DFT) and time-dependent DFT to predict their ground-state electronic structures and the UV–vis spectra, and the open circuit voltages (Vocs) of organic solar cells of D2-A-D1-A-D2/PC71BM. Based on the calculated results, we find that bithiophene thiazolo[5,4-d]thiazole siloldithiophene (BTTS) (D2 = bithiophene, A = thiazolo[5,4-d]thiazole, D1 = silol dithiophene) possesses the highest lowest unoccupied molecular orbital (−2.60 eV) and the lowest highest occupied molecular orbital (−5.33 eV) energies, and the strongest absorption in the visible region. Besides, the solar cell of BTTS/PC71BM has the highest Voc of 1.02 V. These results indicate that it may be a promising donor. In contrast, bithiophene benzobisthiadiazole siloldithiophene (BBBS) (A = benzobisthiadiazole) has low absorption strength in the visible region, which indicates that it may not be a suitable donor material. 相似文献
3.
《中国物理 B》2021,30(5):57303-057303
A novel super-junction LDMOS with low resistance channel(LRC), named LRC-LDMOS based on the silicon-oninsulator(SOI) technology is proposed. The LRC is highly doped on the surface of the drift region, which can significantly reduce the specific on resistance(Ron,sp) in forward conduction. The charge compensation between the LRC, N-pillar,and P-pillar of the super-junction are adjusted to satisfy the charge balance, which can completely deplete the whole drift,thus the breakdown voltage(BV) is enhanced in reverse blocking. The three-dimensional(3 D) simulation results show that the BV and R_(on,sp) of the device can reach 253 V and 15.5 mΩ·cm~2, respectively, and the Baliga's figure of merit(FOM = BV~2/R_(on,sp)) of 4.1 MW/cm~2 is achieved, breaking through the silicon limit. 相似文献
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Markus Jarvid Anette Johansson Jonas M. Bjuggren Harald Wutzel Villgot Englund Stanislaw Gubanski Christian Müller Mats R. Andersson 《Journal of Polymer Science.Polymer Physics》2014,52(16):1047-1054
The synthesis and physico‐chemical properties of seven benzil‐type voltage stabilizers are reported. The benzil core is substituted with alkyl chains of different length that are linked to the benzil core via an ester, ether, or tertiary amine group. All additives can be melt‐processed with low‐density polyethylene (LDPE). Fourier‐transform infrared spectroscopy confirms that benzil compounds are not affected by the LDPE cross‐linking reaction induced by dicumyl peroxide. Moreover, a combination of gel content measurements, thermal analysis, and small‐angle X‐ray scattering indicates that the presence of benzil voltage stabilizers does not significantly alter the microstructure of cross‐linked polyethylene (XLPE). Electrical tree inhibition experiments under high‐voltage alternating current conditions show that all investigated additives substantially enhance the dielectric strength of the insulating material at a concentration of only 10 mmol kg?1. The highest improvement in dielectric strength, of more than 70% with respect to reference XLPE, is obtained with voltage stabilizers, which carry short (methyl) side chains that are linked to the benzil core via an ester or tertiary amine group. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014 , 52, 1047–1054 相似文献
9.
Targeted Delivery of Vaccine to Dendritic Cells by Chitosan Nanoparticles Conjugated with a Targeting Peptide Ligand Selected by Phage Display Technique 下载免费PDF全文
10.
《Angewandte Chemie (International ed. in English)》2017,56(8):2183-2186
We herein describe the engineering of E. coli strains that display orthogonal tags for immobilization on their surface and overexpress a functional heterologous “protein content” in their cytosol at the same time. Using the outer membrane protein Lpp‐ompA, cell‐surface display of the streptavidin‐binding peptide, the SpyTag/SpyCatcher system, or a HaloTag variant allowed us to generate bacterial strains that can selectively bind to solid substrates, as demonstrated with magnetic microbeads. The simultaneous cytosolic expression of functional content was demonstrated for fluorescent proteins or stereoselective ketoreductase enzymes. The latter strains gave high selectivities for specific immobilization onto complementary surfaces and also in the whole‐cell stereospecific transformation of a prochiral CS‐symmetric nitrodiketone. 相似文献