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Hongjuan Chen Peng Fan Xingxin Tu Hui Min Xianyong Yu Xiaofang Li Ju‐Lan Zeng Shaowei Zhang Peng Cheng 《化学:亚洲杂志》2019,14(20):3611-3619
The hydrothermal reaction of Zn2+ ions with a mixture of two ligands, Hcptpy and H3btc (Hcptpy=4‐(4‐carboxyphenyl)‐2,2′:4′,4′′‐terpyridine; H3btc=1,3,5‐benzenetricarboxylic acid), led to the formation of a 3D metal–organic framework (MOF) with 1D channels, [Zn2(cptpy)(btc)(H2O)]n ( 1 ), which was structurally characterized by using single‐crystal X‐ray diffraction (SXRD). In MOF 1 , two independent Zn2+ ions were interconnected by btc3? ligands to form a 1D chain, whilst adjacent Zn2+ ions were alternately bridged by cptpy? ligands to generate a 2D sheet, which was further linked by 1D chains to form a 3D framework with a new (3,3,4,4)‐connected topology. Furthermore, compound 1 also exhibited excellent stability towards air and water and, more importantly, luminescence experiments indicated that it could serve as a probe for the sensitive detection of paraquat (PAQ) and Fe3+ ions in aqueous solution. 相似文献
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Tao Wenyan Tu Xinman Chen Jian Zhu Qian Zhu Yongqian 《Journal of Solid State Electrochemistry》2019,23(5):1613-1619
Journal of Solid State Electrochemistry - Here, a nanoporous gold electrode (NAu) was reported with a unique cone-shape nanohole structure for electrochemical sensing of nitric oxide (NO), which... 相似文献
4.
Lingyan Gao Mingjun Li Svenja Ehrmann Zhaoxu Tu Rainer Haag 《Angewandte Chemie (International ed. in English)》2019,58(11):3645-3649
Bacterial biofilms are difficult to eradicate because they are less susceptible to antibiotics and more easily develop resistance. Therefore, there is an urgent need for new materials that can combat planktonic bacteria and disrupt established biofilms. To tackle this challenge, we design a multifunctional zwitterionic pillar[5]arene, which can self‐assemble into weakly positively charged nanoaggregates that exhibit antibacterial activity against Gram‐negative Escherichia coli (DH5α) and Gram‐positive Staphylococcus aureus (SH1000) bacterial strains in solution. In addition, the zwitterionic pillar[5]arene can efficiently disrupt pre‐existing Escherichia coli (DH5α) biofilms and kill the biofilm‐enclosed bacteria without rapid generation of resistance. 相似文献
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Structural Chemistry - Alternariol and alternariol monomethyl ether are mycotoxins occasionally found in food and beverages that have been contaminated by certain fungi of the Alternaria genus.... 相似文献
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A design of ultrathin crystalline silicon solar cell with Si3 N4 circular truncated cone holes(CTCs) arrays on the top is proposed. In this article, we perform an optical simulation of the structure. The finite-difference time-domain method is used to calculate the optical absorption of different periods, radius of top and bottom circles and depth of Si3 N4 CTCs. The short-circuit current density generated by the optimized cells(30.17 mA/cm~2) is 32.44% more than the value gained by control group(with flat Si3 N4). Then adding a layer of back silver to allow us to better analyze optical absorption. Later, we simulate the optimization of the same configuration of different silicon thicknesses andfind that our structure does enhance the light absorption. This work uses a combined path towards achieving higher photocurrent ultrathin crystalline silicon solar cells by constructing the texture of anti-reflection coating. 相似文献
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In this paper, we study the Heinz type inequalities for mappings satisfying Poisson’s equation. Some results generalize the ones obtained by Partyka and Sakan. 相似文献
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Micro and nanomotors (MNMs) are micro/nanoscale devices that are able to convert chemical or external energy into mechanical motion. Based on a multitude of propulsion mechanisms, synthetic MNMs have been developed over the past decades for diverse biomedical applications, particularly drug delivery. Herein, we set out the classification of drugs delivered by MNMs, such as small molecules, nucleic acid, peptides, antibodies, and other proteins, and discuss their current limitations and possibilities in in vivo applications. Challenges and future perspectives are also discussed. With the increasing research enthusiasm in this field and the strengthening of multidisciplinary cooperation, intelligent MNMs will appear in the near future, which will have a profound impact on all related fields. 相似文献
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A new star-shaped molecule StOF-Br_3 containing oligofluorenes and halogen atoms(Bromine) has been synthesized and studied by Scanning Tunneling Microscopy(STM) at the highly oriented pyrolytic graphite(HOPG) surface.We have obtained the high-resolution self-assembled STM images,from which the highly ordered and closely packed non-porous arrangements of the StOF-Br_3 molecular selfassemblies at the heptanoic acid/HOPG surface could be observed.The molecular models and selfassembled StOF-Br_3 architectures have been given in the following text.Besides,we have also figured out the surface free energy by the density functional theory(DFT) calculation,which proved that the halogen...halogen interaction was strong enough to stabilize the ordered molecular self-assemblies.This work verifies the existence of bromine...bromine interactions,and meanwhile provides a kind of effective approach for quickly building ordered molecular nanoarchitectures with large areas and different geometries. 相似文献
10.
窄禁带直接带隙半导体材料碲镉汞(Hg1–xCdxTe)是一种在红外探测与自旋轨道耦合效应基础研究方面都具有重要应用意义的材料.本文对单晶生长的体材料Hg0.851Cd0.149Te进行阳极氧化以形成表面反型层,将样品粘贴在压电陶瓷上减薄后进行磁输运测试,在压电陶瓷未加电压时观察到了明显的SdH振荡效应.对填充因子与磁场倒数进行线性拟合,获得样品反型层二维电子气的载流子浓度为ns=1.25×10^16m^-2.在不同磁场下,利用压电陶瓷对样品进行应力调控,观测到具有不同特征的现象,分析应是样品中存在二维电子气与体材料两个导电通道.零磁场下体材料主导的电阻的变化应来源于应力导致的带隙的改变;而高场下产生类振荡现象的原因应为应力导致的二维电子气能级的分裂. 相似文献