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151.
Caterpillar Track Complexes in Template‐Directed Synthesis and Correlated Molecular Motion 下载免费PDF全文
Shiqi Liu Dr. Dmitry V. Kondratuk Dr. Sophie A. L. Rousseaux Dr. Guzmán Gil‐Ramírez Dr. Melanie C. O'Sullivan Jonathan Cremers Prof. Tim D. W. Claridge Prof. Harry L. Anderson 《Angewandte Chemie (International ed. in English)》2015,54(18):5355-5359
Small alterations to the structure of a star‐shaped template totally change its mode of operation. The hexapyridyl template directs the conversion of a porphyrin dimer to the cyclic hexamer, but deleting one pyridine site changes the product to the cyclic decamer, while deleting two binding sites changes the product to the cyclic octamer. This surprising switch in selectivity is explained by the formation of 2:1 caterpillar track complexes, in which two template wheels bind inside the nanoring. Caterpillar track complexes can also be prepared by binding the hexapyridyl template inside the 8‐ and 10‐porphyrin nanorings. NMR exchange spectroscopy (EXSY) experiments show that these complexes exhibit correlated motion, in which the conrotatory rotation of the two template wheels is coupled to rotation of the nanoring track. In the case of the 10‐porphyrin system, the correlated motion can be locked by binding palladium(II) dichloride between the two templates. 相似文献
152.
m‐Xylylene bismaleimide, Compimide ? ? Compimide® is a registered trademark.
MXBI (hereafter MXBI), was developed as a building block for formulating bismaleimide resins with improved processability. MXBI on its own, or in combination with 4,4′‐bismaleimidodiphenylmethane (Compimide MDAB, hereafter MDAB) and with 2,2′‐diallylbisphenol‐A as a co‐monomer, provides very low‐melting resin blends, which can be processed at temperatures around 60–80°C via RTM (Resin Transfer Moulding), VARIM (Vacuum Assisted Resin Infusion Moulding), prepregging, and wet filament winding (FW). Uncured and cured resin properties were evaluated. The mechanical property spectrum of the MXBI/MDAB/diallylbisphenol‐A system with varying MXBI/MDAB ratio shows almost equivalent contributions of MXBI and MDAB to the mechanical properties of a system. Higher MXBI proportions are responsible for lower resin viscosities and hence superior processability. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
MXBI (hereafter MXBI), was developed as a building block for formulating bismaleimide resins with improved processability. MXBI on its own, or in combination with 4,4′‐bismaleimidodiphenylmethane (Compimide MDAB, hereafter MDAB) and with 2,2′‐diallylbisphenol‐A as a co‐monomer, provides very low‐melting resin blends, which can be processed at temperatures around 60–80°C via RTM (Resin Transfer Moulding), VARIM (Vacuum Assisted Resin Infusion Moulding), prepregging, and wet filament winding (FW). Uncured and cured resin properties were evaluated. The mechanical property spectrum of the MXBI/MDAB/diallylbisphenol‐A system with varying MXBI/MDAB ratio shows almost equivalent contributions of MXBI and MDAB to the mechanical properties of a system. Higher MXBI proportions are responsible for lower resin viscosities and hence superior processability. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
153.
Dr. Guang‐Ping Hao Giovanni Mondin Dr. Zhikun Zheng Tim Biemelt Stefan Klosz René Schubel Prof. Alexander Eychmüller Prof. Stefan Kaskel 《Angewandte Chemie (International ed. in English)》2015,54(6):1941-1945
There is significant interest in high‐performance materials that can directly and efficiently capture water vapor, particularly from air. Herein, we report a class of novel porous carbon cuboids with unusual ultra‐hydrophilic properties, over which the synergistic effects between surface heterogeneity and micropore architecture is maximized, leading to the best atmospheric water‐capture performance among porous carbons to date, with a water capacity of up to 9.82 mmol g?1 at P/P0=0.2 and 25 °C (20 % relative humidity or 6000 ppm). Benefiting from properties, such as defined morphology, narrow pore size distribution, and high heterogeneity, this series of functional carbons may serve as model materials for fundamental research on carbon chemistry and the advance of new types of materials for water‐vapor capture as well as other applications requiring combined highly hydrophilic surface chemistry, developed hierarchical porosity, and excellent stability. 相似文献
154.
Christian Wenz Coral Barbas Ángeles López‐Gonzálvez Antonia Garcia Fernando Benavente Victoria Sanz‐Nebot Tim Blanc Gordon Freckleton Philip Britz‐McKibbin Meera Shanmuganathan Francois de l′Escaille Johann Far Rob Haselberg Sean Huang Carolin Huhn Martin Pattky David Michels Si Mou Feng Yang Christian Neusuess Nora Tromsdorf Edward E.K. Baidoo Jay D. Keasling SungAe Suhr Park 《Journal of separation science》2015,38(18):NA-NA
A collaborative study on the robustness and portability of a capillary electrophoresis‐mass spectrometry method for peptide mapping was performed by an international team, consisting of 13 independent laboratories from academia and industry. All participants used the same batch of samples, reagents and coated capillaries to run their assays, whereas they utilized the capillary electrophoresis‐mass spectrometry equipment available in their laboratories. The equipment used varied in model, type and instrument manufacturer. Furthermore, different types of sheath‐flow capillary electrophoresis–mass spectrometry interfaces were used. Migration time, peak height and peak area of ten representative target peptides of trypsin‐digested bovine serum albumin were determined by every laboratory on two consecutive days. The data were critically evaluated to identify outliers and final values for means, repeatability (precision within a laboratory) and reproducibility (precision between laboratories) were established. For relative migration time the repeatability was between 0.05 and 0.18% RSD and the reproducibility between 0.14 and 1.3% RSD. For relative peak area repeatability and reproducibility values obtained were 3–12 and 9–29% RSD, respectively. These results demonstrate that capillary electrophoresis‐mass spectrometry is robust enough to allow a method transfer across multiple laboratories and should promote a more widespread use of peptide mapping and other capillary electrophoresis‐mass spectrometry applications in biopharmaceutical analysis and related fields. 相似文献
155.
Thorsten vomStein Tim denHartog Julien Buendia Spas Stoychev Jakob Mottweiler Carsten Bolm Jürgen Klankermayer Walter Leitner 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(20):5957-5961
Ruthenium–triphos complexes exhibited unprecedented catalytic activity and selectivity in the redox‐neutral C C bond cleavage of the β‐O‐4 lignin linkage of 1,3‐dilignol model compounds. A mechanistic pathway involving a dehydrogenation‐initiated retro‐aldol reaction for the C C bond cleavage was proposed in line with experimental data and DFT calculations. 相似文献
156.
Frontispiece: Gd‐DTPA‐Dopamine‐Bisphytanyl Amphiphile: Synthesis,Characterisation and Relaxation Parameters of the Nanoassemblies and Their Potential as MRI Contrast Agents 下载免费PDF全文
157.
Jodie N. Haigh Ya‐mi Chuang Brooke Farrugia Richard Hoogenboom Paul D. Dalton Tim R. Dargaville 《Macromolecular rapid communications》2016,37(1):93-99
A new method for fabricating hydrogels with intricate control over hierarchical 3D porosity using microfiber porogens is presented. Melt electrospinning writing of poly(ε‐caprolactone) is used to create the sacrificial template leading to hierarchical structuring consisting of pores inside the denser poly(2‐oxazoline) hydrogel mesh. This versatile approach provides new opportunities to create well‐defined multilevel control over interconnected pores with diameters in the lower micrometer range inside hydrogels with potential applications as cell scaffolds with tunable diffusion and transport of, e.g., nutrients, growth factors or therapeutics.
158.
This paper concerns smoothing by infimal convolution for two large classes of functions: convex, proper and lower semicontinous as well as for (the nonconvex class of) convex-composite functions. The smooth approximations are constructed so that they epi-converge (to the underlying nonsmooth function) and fulfill a desirable property with respect to graph convergence of the gradient mappings to the subdifferential of the original function under reasonable assumptions. The close connection between epi-convergence of the smoothing functions and coercivity properties of the smoothing kernel is established. 相似文献
159.
This paper proposes that the theory of local rules provides a model for explaining organizational behavior as an emergent property of a fitness landscape. While local rule theory has its genesis in evolutionary biology, this paper links it to work in computational mathematical organizational theory. It further proposes that there are conditions, characterized by coadaptation, under which rules will survive in relatively stable forms, and other conditions, characterized by competition, under which local rules will change. The paper then discusses how catastrophe analysis can provide insights into changing patterns of organizational interactions. A discussion of methodology outline shows developments in agent-based simulation modeling can contribute to the development of local rule theory. 相似文献
160.
The transition from simulation software to optimization software is often quite cumbersome and error prone. With Algorithmic Differentiation(AD) a semi automatic transition can be achieved, but most of the times the performance characteristics of the modified software are not clear in advance. Therefore the performance model from Griewank is tested against real world examples and an automated measurement for the performance characteristics of the hardware is proposed. This enables a more accurate calculation of the performance characteristics of the modified software. (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献