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991.
Transfer of Two‐Dimensional Oligonucleotide Patterns onto Stereocontrolled Plasmonic Nanostructures through DNA‐Origami‐Based Nanoimprinting Lithography 下载免费PDF全文
Yinan Zhang Prof. Jie Chao Prof. Huajie Liu Fei Wang Prof. Shao Su Bing Liu Prof. Lan Zhang Dr. Jiye Shi Prof. Lihua Wang Prof. Wei Huang Prof. Lianhui Wang Prof. Chunhai Fan 《Angewandte Chemie (International ed. in English)》2016,55(28):8036-8040
The precise functionalization of self‐assembled nanostructures with spatial and stereocontrol is a major objective of nanotechnology and holds great promise for many applications. Herein, the nanoscale addressability of DNA origami was exploited to develop a precise copy‐machine‐like platform that can transfer two‐dimensional oligonucleotide patterns onto the surface of gold nanoparticles (AuNPs) through a deliberately designed toehold‐initiated DNA displacement reaction. This strategy of DNA‐origami‐based nanoimprinting lithography (DONIL) demonstrates high precision in controlling the valence and valence angles of AuNPs. These DNA‐decorated AuNPs act as precursors in the construction of discrete AuNP clusters with desired chirality. 相似文献
992.
Ze‐Fan Yao Zi‐Yuan Wang Hao‐Tian Wu Yang Lu Qi‐Yi Li Lin Zou Jie‐Yu Wang Jian Pei 《Angewandte Chemie (International ed. in English)》2020,59(40):17467-17471
Controlling the solution‐state aggregation of conjugated polymers for producing specific microstructures remains challenging. Herein, a practical approach is developed to finely tune the solid‐state microstructures through temperature‐controlled solution‐state aggregation and polymer crystallization. High temperature generates significant conformation fluctuation of conjugated backbones in solution, which facilitates the polymer crystallization from solvated aggregates to orderly packed structures. The polymer films deposited at high temperatures exhibit less structural disorders and higher electron mobilities (up to two orders of magnitude) in field‐effect transistors, compared to those deposited at low temperatures. This work provides an effective strategy to tune the solution‐state aggregation to reveal the relationship between solution‐state aggregation and solid‐state microstructures of conjugated polymers. 相似文献
993.
LU Shi-xiang JIN Guo-xin ** HU Ning-hai JIA Heng-qing . Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun P. R. China . College of Chemistry Jinlin University Changchun P. R. China 《高等学校化学研究》2002,18(4)
IntroductionThe chemistry of chalcogen organometalliccomplexs has become one of the most activebranches in modern chemistry[1] .Itnot only showsthe coordinate variability of organometalliccomplexes but also is applied to studying thereaction mechanism of biologic enzyme[2 ] and thecatalysis of dehydrogenation or hydrogenation inindustry[3] .It is known that transition metalcomplexes react with cyclopentadienyl orsubstituted cyclopentadienyl to form halfsandwichcomplexes with different structur… 相似文献
994.
995.
Terminal phosphino groups of [Re2(CO)9(η1-P-P)] (P-P = diphosphines) are activated towards oxidation by Me3NO. The respective reactions of Me3NO with [Re2(CO)9{η1-P(o-anisyl)2(CH2)3PPh2}], [Re2(CO)9{η1-PPh2(CH2)3P(o-anisyl)2}] and [Re2(CO)9(η1-trans-PPh2CHCHPPh2)] were studied to investigate the mechanism of this oxidation. The results are consistent with an intramolecular pathway involving a cyclic intermediate, without exchange of the coordinated and terminal phosphino groups. A mechanism which involves an interaction of the terminal phosphino group with a carbonyl ligand is proposed. In sharp contrast to eq-[Re2(CO)9(η1-P-P)] (P-P = Ph2P(CH2)nPPh2, n = 1-6), eq-[Re2(CO)9(η1-trans-PPh2CHCHPPh2)] appears to be indefinitely stable towards equatorial → axial isomerization at room temperature, thus, allowing its crystal structure to be determined. 相似文献
996.
A new complex of copper(II) picrate (pic) with 1, 3‐bis(1‐allaylbenzimidazol‐2‐yl)‐2‐oxopropane (aobb), with the composition [Cu(aobb)2](pic)2, was synthesized and characterized. The crystal structure of the copper(II) complex revealed that the coordination environment around the central copper(II) atom is a distorted octahedral arrangement. Electronic absorption spectroscopy, ethidium bromide displacement experiments and viscosity measurements indicate that the ligand and the CuII complex can strongly bind to calf thymus DNA, presumably by an intercalation mechanism. Furthermore, the antioxidant activity of the CuII complex was determined by superoxide and hydroxyl radical scavenging method in vitro, which indicate that the CuII complex has the activity to suppress OH · and O2 · –. 相似文献
997.
LIU Langa JI Ya-Lia JIA Dian-Zenga② YU Kai-Beib a 《结构化学》2003,22(5):568-572
1 INTRODUCTION In recent years, investigations on the com- pounds containing hydrazide or hydrazone moieties have been increased considerably because of their potentially biological activities, especially as poten- tial inhibitors for many enzymes[1~5]. The presence of weak molecular interactions such as hydrogen- bonding controls the conformational and structural features which are important to the drug action[6, 7]. We have synthesized the photochromic compounds of pyrazolone thiosemi… 相似文献
998.
Two aggregation-induced emission (AIE) macrocycles (DMP[5]-TPE and PCP[5]-TPE) were prepared by embedding Tetraphenylethene (TPE) unit into the skeletons of Dimethoxypillar[5]arene (DMP[5]) and [15]Paracyclophane ([15]PCP) at meso position, respectively. In crystal, the PCP[5]-TPE showed a distorted cavity, and the incubation of hexane inside the DMP[5]-TPE cavity caused a distinct change in the molecular conformation compared to PCP[5]-TPE. There was no complexation between PCP[5]-TPE and 1,4-dicyanobutane (DCB). UV absorption experiments showed the distorted cavity of DMP[5]-TPE hindered association with DCB. 相似文献
999.
In this paper, we propose a globally hyperbolic regularization to the general Grad's moment system in multidimensional spaces. Systems with moments up to an arbitrary order are studied. The characteristic speeds of the regularized moment system can be analytically given and depend only on the macroscopic velocity and the temperature. The structure of the eigenvalues and eigenvectors of the coefficient matrix is fully clarified. The regularization together with the properties of the resulting moment systems is consistent with the simple one‐dimensional case discussed in 1. In addition, all characteristic waves are proven to be genuinely nonlinear or linearly degenerate, and the studies on the properties of rarefaction waves, contact discontinuities, and shock waves are included. © 2014 Wiley Periodicals, Inc. 相似文献
1000.