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101.
Dr. Paula Gómez‐Álvarez Prof. Sofia Calero 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(52):18705-18708
The separation of carbon dioxide from flue gas is essential for the reduction of greenhouse gas emissions. In adsorptive methods, the challenge lies in the choice of suitable porous materials. Among all zeolite topologies, a number of adsorbents with pore dimensions in the range of the guest molecules were identified to allow an excellent separation by diffusion, and MRE and AFO zeolite topologies appear to be the best candidates based on equilibrium adsorption. Also, it was found that the behavior of this gas mixture in DFT and APD zeolites differed from the normal behavior. 相似文献
102.
Qing-Long Bai Chun-Hua Zhang Juan-Juan Song Jing-Hai Liu Yan-Chun Feng Li-Mei Duan Chuan-Hui Cheng 《中国化学快报》2016,27(5):764-768
A metal-free purple H2Pc single crystal was synthesized by a facile solvothermal method, and its solubility and near-infrared (NIR) optical properties were also investigated due to its potential applications as a light-emitting layer for OLEDs. The H2Pc single crystal is insoluble in 1-chlorine naphthalene and other organic solvents. It gives a wide absorption in the range from 620 nm to 679 nm and a wide emission in near 922 nm. As an active light-emitting layer, H2Pc was employed to fabricate electroluminescent (EL) devices with a structure of ITO/NPB (30 nm)/Alq3:H2Pc (30 nm)/BCP (20 nm)/Alq3 (20 nm)/Al. The emission center is at 936 nm when the H2Pc doping concentration is 20 wt%. The doping concentration strongly governs the emission intensity. When doping concentration decreases from 10 wt% to 1 wt%, the emission intensity remarkably fades, and simultaneously the emission center undergoes a blue shift. 相似文献
103.
利用Minitab软件设计实验,以超高分子量聚乙烯纤维(UHMWPE)为原料,研究了在不同的超临界CO_2流体状态下,处理压力、温度和时间等因素对三羟甲基丙烷三甲基丙烯酸酯(TMPTMA)渗入率的影响,确定了最佳因素设置范围;通过单因子实验优化了超临界CO_2处理工艺,并对经过电子束辐照的UHMWPE纤维凝胶含量和蠕变率进行了测试。研究结果表明:处理温度对TMPTMA的渗入率影响最大,其次为压力,时间的影响最小,确定了最优工艺条件为处理压力25MPa,温度80℃,时间30min;TMPTMA渗入率越高,电子束辐照后UHMWPE纤维的增感辐照交联效应和抗蠕变效果越好。 相似文献
104.
Intermolecular Stetter reaction of aromatic aldehydes with (E)-(2-nitrovinyl)cyclohexane catalyzed by thiazolium A has been developed. The reaction rate and efficiency are profoundly impacted by the presence of thiourea B. The reaction affords moderate to good yields of the Stetter product. Some factors influencing yield were discussed. 相似文献
105.
Synthesis of 5‐substituted 1H‐tetrazoles using a recyclable heterogeneous nanonickel ferrite catalyst 下载免费PDF全文
An efficient method was developed for the [2 + 3] cycloaddition of sodium azide with nitriles to afford 5‐substituted 1H‐tetrazoles using nanonickel ferrite (NiFe2O4) as an effective heterogeneous catalyst in dimethylformamide. The main advantages of this method are high yields, simple methodology and easy work‐up. The catalyst can be recovered and reused for several cycles with predictable activity. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
106.
Frontispiece: Glycoluril‐Derived Molecular Clips are Potent and Selective Receptors for Cationic Dyes in Water 下载免费PDF全文
107.
From Binuclear Complexes to Molecular Necklaces: Incorporating Flexible Ligands into Rotaxanes 下载免费PDF全文
Dr. Elizabeth Viljoen Dr. Kelong Zhu Prof. Stephen J. Loeb 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(22):7479-7484
The conversion of binuclear complexes into larger molecular necklaces can be achieved through rigidifying flexible ligands by threading them through a crown ether to form either an interpenetrated [2]pseudorotaxane or a permanently interlocked [2]rotaxane. The resulting complexes and assemblies are characterized by 1H and DOSY NMR in solution and single‐crystal X‐ray diffraction in the solid‐state. 相似文献
108.
Highly Phosphorescent Crystals of Square‐Planar Platinum Complexes with Chiral Organometallic Linkers: Homochiral versus Heterochiral Arrangements,Induced Circular Dichroism,and TD‐DFT Calculations 下载免费PDF全文
Dr. Hugo Sesolis Dr. Julien Dubarle‐Offner Dr. Carmen K. M. Chan Emmanuel Puig Geoffrey Gontard Pierre Winter Prof. Andrew L. Cooksy Prof. Vivian W. W. Yam Dr. Hani Amouri 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(24):8032-8037
A novel class of chiral luminescent square‐planar platinum complexes with a π‐bonded chiral thioquinonoid ligand is described. Remarkably the presence of this chiral organometallic ligand controls the aggregation of this square planar luminophor and imposes a homo‐ or hetero‐chiral arrangement at the supramolecular level, displaying non‐covalent Pt–Pt and π–π interactions. Interestingly these complexes are highly luminescent in the crystalline state and their photophysical properties can be traced to their aggregation in the solid state. A TD‐DFT calculation is obtained to rationalize this unique behavior. 相似文献
109.
Lewis Acids as Activators in CBS‐Catalysed Diels–Alder Reactions: Distortion Induced Lewis Acidity Enhancement of SnCl4 下载免费PDF全文
Dr. Alexander R. Nödling Robert Möckel Dr. Ralf Tonner Prof. Dr. Gerhard Hilt 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(37):13171-13180
The effect of several Lewis acids on the CBS catalyst (named after Corey, Bakshi and Shibata) was investigated in this study. While 2H NMR spectroscopic measurements served as gauge for the activation capability of the Lewis acids, in situ FT‐IR spectroscopy was employed to assess the catalytic activity of the Lewis acid oxazaborolidine complexes. A correlation was found between the Δδ(2H) values and rate constants kDA, which indicates a direct translation of Lewis acidity into reactivity of the Lewis acid–CBS complexes. Unexpectedly, a significant deviation was found for SnCl4 as Lewis acid. The SnCl4–CBS adduct was much more reactive than the Δδ(2H) values predicted and gave similar reaction rates to those observed for the prominent AlBr3–CBS adduct. To rationalize these results, quantum mechanical calculations were performed. The frontier molecular orbital approach was applied and a good correlation between the LUMO energies of the Lewis acid–CBS–naphthoquinone adducts and kDA could be found. For the SnCl4–CBS–naphthoquinone adduct an unusual distortion was observed leading to an enhanced Lewis acidity. Energy decomposition analysis with natural orbitals for chemical valence (EDA‐NOCV) calculations revealed the relevant interactions and activation mode of SnCl4 as Lewis acid in Diels–Alder reactions. 相似文献
110.
Specificity of Furanoside–Protein Recognition through Antibody Engineering and Molecular Modeling 下载免费PDF全文
Dr. Parnian Lak Spandana Makeneni Prof. Dr. Robert J. Woods Prof. Dr. Todd L. Lowary 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(3):1138-1148
Recognition of furanosides (five‐membered ring sugars) by proteins plays important roles in host–pathogen interactions. In comparison to their six‐membered ring counterparts (pyranosides), detailed studies of the molecular motifs involved in the recognition of furanosides by proteins are scarce. Here the first in‐depth molecular characterization of a furanoside–protein interaction system, between an antibody (CS‐35) and cell wall polysaccharides of mycobacteria, including the organism responsible for tuberculosis is reported. The approach was centered on the generation of the single chain variable fragment of CS‐35 and a rational library of its mutants. Investigating the interaction from various aspects revealed the structural motifs that govern the interaction, as well as the relative contribution of molecular forces involved in the recognition. The specificity of the recognition was shown to originate mainly from multiple CH–π interactions and, to a lesser degree, hydrogen bonds formed in critical distances and geometries. 相似文献