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121.
Dr. Pavel A. Petrov Evgeny M. Kadilenko Dr. Taisiya S. Sukhikh Dr. Ilia V. Eltsov Prof. Artem L. Gushchin Prof. Vladimir A. Nadolinny Prof. Maxim N. Sokolov Prof. Nina P. Gritsan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(64):14688-14699
Interaction of the tetradentate redox-active 6,6′-[1,2-phenylenebis(azanediyl)]bis(2,4-di-tert-butylphenol) (H4L) with TeCl4 leads to neutral diamagnetic compound TeL ( 1 ) in high yield. The molecule of 1 has a nearly planar TeN2O2 fragment, which suggests the formulation of 1 as TeIIL2−, in agreement with the results of DFT calculations and QTAIM and NBO analyses. Reduction of 1 with one equivalent of [CoCp2] leads to quantitative formation of the paramagnetic salt [CoCp2]+[ 1 ].−, which was characterised by single-crystal XRD. The solution EPR spectrum of [CoCp2]+[ 1 ].− at room temperature features a quintet due to splitting on two equivalent 14N nuclei. Below 150 K it turns into a broad singlet line with two weak satellites due to the splitting on the 125Te nucleus. Two-component relativistic DFT calculations perfectly reproduce the a(14N) HFI constants and A∥(125Te) value responsible for the low-temperature satellite splitting. Calculations predict that the additional electron in 1 .− is localised mainly on L, while the spin density is delocalised over the whole molecule with significant localisation on the Te atom (≥30 %). All these data suggest that 1 .− can be regarded as the first example of a structurally characterised monomeric tellurium–nitrogen radical anion. 相似文献
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123.
Dr. Ilia Kochetygov Jocelyn Roth Dr. Jordi Espín Sophia Pache Dr. Anita Justin Till Schertenleib Dr. Nazanin Taheri Dr. Dmitry Chernyshov Prof. Wendy L. Queen 《Angewandte Chemie (International ed. in English)》2023,62(16):e202215595
The design of metal–organic frameworks (MOFs) having large pore sizes and volumes often requires the use of complex organic ligands, currently synthesized using costly and time-consuming palladium-catalyzed coupling chemistry. Thus, in the present work, a new strategy for ligand design is reported, where piperazine and dihydrophenazine units are used as substitutes for benzene rings, which are the basic building block of most MOF ligands. This chemistry, which is based on simple, nucleophilic aromatic substitution (SNAr) reactions, is used for the transition metal catalyst-free construction of 21 new, carboxylate-based ligands with varying sizes, shapes, and denticity and 15 linear di- and tetra-nitriles. Moreover, to demonstrate the utility of the ligands as building blocks, 16 new structurally diverse MOFs having surface areas up to 3100 m2 g−1 were also synthesized. 相似文献
124.
Désirée Sauter Martin Schröter Christoph Frey Cornelia Weber Ulrike Mersdorf Jan-Willi Janiesch Ilia Platzman Joachim P. Spatz 《Macromolecular bioscience》2023,23(8):2200437
Imitation of cellular processes in cell-like compartments is a current research focus in synthetic biology. Here, a method is introduced for assembling an artificial cytoskeleton in a synthetic cell model system based on a poly(N-isopropyl acrylamide) (PNIPAM) composite material. Toward this end, a PNIPAM-based composite material inside water-in-oil droplets that are stabilized with PNIPAM-functionalized and commercial fluorosurfactants is introduced. The temperature-mediated contraction/release behavior of the PNIPAM-based cytoskeleton is investigated. The reversibility of the PNIPAM transition is further examined in bulk and in droplets and it could be shown that hydrogel induced deformation could be used to controllably manipulate droplet-based synthetic cell motility upon temperature changes. It is envisioned that a combination of the presented artificial cytoskeleton with naturally occurring components might expand the bandwidth of the bottom-up synthetic biology. 相似文献
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We discuss how the cosmic ray signals reported by the PAMELA and ATIC/PPB-BETS experiments may be understood in a Standard Model (SM) framework supplemented by type II seesaw and a stable SM singlet scalar boson as dark matter. A particle physics explanation of the ‘boost’ factor can be provided by including an additional SM singlet scalar field. 相似文献
127.
Stephen O. Ojwach Ilia A. Guzei J. Darkwa 《Journal of organometallic chemistry》2009,694(9-10):1393-1399
Reactions of 2-(3,5-dimethylpyrazol-1-ylmethyl)pyridine (L1) and 2-(3,5-di-tert-butylpyrazol-1-ylmethyl)pyridine (L2) with either [PdClMe(COD)] or [PdCl2(COD)] gave the mononuclear palladium complexes [PdCl2(L1)] (1), [PdClMe(L1)] (2) [PdCl2(L2)] (3) and [PdClMe(L2)] (4) in good yields. All compounds were characterized by NMR spectrometry, mass spectrometry, elemental analyses and also by single crystal X-ray crystallography for complexes 1, 3, and 4. The reaction of 2 with NaBAr4 in NCMe gave the salt, [[PdMeNCMe(L3)]BAr4 (5), in good yield. This salt was used as a catalyst to oligomerize ethylene at high pressures to branched polyethylene, but catalytic activity was low. The reaction of 2 with SO2 and CO formed the respective insertion products [PdClS(O)2Me(L1)] (6) and [PdClC(O)Me(L1)] (7). 相似文献
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129.
One-shot pseudo-timestepping [1, 2] has proven to be a powerful approach for the solution of optimal design problems in engineering applications. It blends well in within pre-existing pseudo-timestepping simulation solvers. The goal of this approach is to transform the equations for the necessary optimality conditions of the optimal design problem into an ordinary differential equation (ODE) and then solve the pseudo-time embedded state, co-state and design equations all at once. Similar approaches have been considered in [4, 5]. An application of this method to a real-world example within the MEGADESIGN-Project has been presented in [3]. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
130.
A coating system based on different combinations of natural magnetite and carbon black filled epoxy resin has been developed. The influence of filler concentration and the ordering of the layers in the absorbing structure on the coefficients of attenuation and reflection of the electromagnetic waves in the frequency range 6.5‐12.0 GHz have been investigated. The results show that the coating system (total thickness of about 2.5‐3.0 mm) developed can be successfully used to reduce the overall signature and to prevent scattering from the sharp edges of complex shaped objects by attenuating surface currents. 相似文献