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981.
Julie P. Vanegas Amanda Reusch Mark J. Fink Brian S. Mitchell 《Particle & Particle Systems Characterization》2023,40(11):2300052
Alkanes such as n-hexane have been used as co-solvents in the production of functionalized semiconductor nanoparticles from alkenes and alkynes using Reactive High Energy Ball Milling (RHEBM) under the assumption that they are non-reactive under typical milling conditions. In this paper, a comparative study with two hydrocarbon solvents of comparable chain length, 1-hexyne, and n-hexane, and their milling products using three different commercially available silicon precursors, namely single crystal silicon wafers and polycrystalline particles having a nominal size of 4 µm and 1 mm, is reported. It is found that nanoparticle formation and surface functionalization in all the three silicon systems occurs only with 1-hexyne; n-hexane is non-reactive and does not lead to appreciable functionalized nanoparticle formation under the conditions studied. Nanoparticles (where formed) and microparticle byproducts of appropriate samples are characterized by Transmission electronic microscope (TEM), Fourier transform infrared (FTIR), Photoluminiscence spectroscopy (PL), Nuclear magnetic resonance 1H/13C NMR, and thermogravimetry TGA to separately confirm nanoparticle formation and surface functionalization. 相似文献
982.
Vamshikrishna Reddy Sammeta Brian M. Anderson John D. Norris Chad D. Torrice Carstyn Joiner Shubin Liu Haoxi Li Konstantin I. Popov Sean W. Fanning Donald P. McDonnell Timothy M. Willson 《Helvetica chimica acta》2023,106(9):e202300097
Synthetic, structural, and computational approaches were used to solve the puzzle as to how a phenolic nonsteroidal estrogen 1 with only a single H-bond to its receptor was more potent than an isomer 2 which formed an intricate network of H-bonds. Synthesis of a series of substituted phenols revealed that pKa was not a determinant of estrogenic activity. First-principles calculation also failed to explain the difference in activity of 1 and 2 . Molecular dynamics revealed that 1 formed a more stable receptor complex compared to 2 , which may explain its increased activity despite forming fewer apparent H-bonds with the protein. 相似文献
983.
We characterize the endomorphisms of the semigroup of all order-preserving mappings on a finite chain. We show that there are three types of endomorphism: automorphisms, constants, and a certain type of endomorphism with two idempotents in the image. 相似文献
984.
Hong-Lei Xu Chad Studvick Dr. Chao Liu Dr. Yuan Xue Prof. Dr. Ivan A. Popov Prof. Dr. Zhong-Ming Sun 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(64):e202202651
Group 14 endohedral clusters containing a metal center inside usually possess a single cage topological structure, but here an unexpected single-metal-filled double-cage cluster, [Pt@Sn17]4− ( 1 a ) is reported. It can be seen as a combination of the more extended Pt-filled [Pt@Sn9] cage and hollow [Sn9] cage sharing a central Sn atom, which is offset from the central position. This double-cage species represents the largest group 14 intermetalloid cluster encapsulating a single transition metal atom. DFT calculations show that the capsule-like architecture of [Sn17]4−, similar to that found in [Pt2@Sn17]4−, is unstable if filled with a single Pt atom and collapses to the title cluster 1 a upon geometry optimization. Deviation of the central Sn atom occurs due to the vibronic coupling as a consequence of pseudo-Jahn-Teller distortion leading to the bent Cs-symmetrical structure, in contrast to the more symmetrical D2d cage previously reported in [Ni2@Sn17]4−. 相似文献
985.
Rico Mia I. Lebedenko Charlotta G. Mitchell Saige M. Banerjee Ipsita A. 《Molecular diversity》2022,26(5):2717-2743
Molecular Diversity - In this work, for the first time, we designed derivatives of beta-D-glucosyloxy-3-hydroxy-trans-stiblene-2-carboxylic acid (GHS), by conjugating GHS with tumor targeting... 相似文献
986.
987.
Aurélien R. Willauer Dr. Chad T. Palumbo Dr. Rosario Scopelliti Dr. Ivica Zivkovic Iskander Douair Prof. Laurent Maron Prof. Marinella Mazzanti 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(9):3577-3581
The synthesis of lanthanides other than cerium in the oxidation state +IV has remained a desirable but unmet target until recently, when two examples of TbIV with saturated coordination spheres were isolated. Here we report the third example of an isolated molecular complex of terbium(IV), where the supporting siloxide ligands do not saturate the coordination sphere. The fully characterized six-coordinate complex [TbIV(OSiPh3)4(MeCN)2], 2 -TbPh, shows high stability and the labile MeCN ligands can be replaced by phosphinoxide ligands. Computational studies suggest that the stability is due to a strong π(O−Tb) interaction which is stronger than in the previously reported TbIV complexes. Cyclic-voltammetry experiments demonstrate that non-binding counterions contribute to the stability of TbIV in solution by destabilizing the +III oxidation state, while alkali ions promote TbIV/TbIII electron transfer. 相似文献
988.
989.
Coro Echeverria Miguel Rubio Geoffrey R. Mitchell Anna Roig Daniel López 《Journal of Polymer Science.Polymer Physics》2015,53(11):814-821
We have succeeded in the preparation of electrospun fibers of polystyrene incorporating a metallo‐organic polymer of [Fe (II) (4‐octadecyl‐1,2,4‐triazole)3(ClO4)2]n. The obtained fibers have diameters in the range 2–4 µm and show the characteristic spin‐crossover transition associated with the metallo‐organic polymer. The structure of both, polystyrene and the metallo‐organic polymer, in the fibers was also studied. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 814–821 相似文献
990.
Jingshan S. Du Peng-Cheng Chen Dr. Brian Meckes Dr. Zhuang Xie Jinghan Zhu Yuan Liu Prof. Vinayak P. Dravid Prof. Chad A. Mirkin 《Angewandte Chemie (International ed. in English)》2017,56(26):7625-7629
Multicomponent nanoparticles can be synthesized with either homogeneous or phase-segregated architectures depending on the synthesis conditions and elements incorporated. To understand the parameters that determine their structural fate, multicomponent metal-oxide nanoparticles consisting of combinations of Co, Ni, and Cu were synthesized by using scanning probe block copolymer lithography and characterized using correlated electron microscopy. These studies revealed that the miscibility, ratio of the metallic components, and the synthesis temperature determine the crystal structure and architecture of the nanoparticles. A Co-Ni-O system forms a rock salt structure largely owing to the miscibility of CoO and NiO, while Cu-Ni-O, which has large miscibility gaps, forms either homogeneous oxides, heterojunctions, or alloys depending on the annealing temperature and composition. Moreover, a higher-ordered structure, Co-Ni-Cu-O, was found to follow the behavior of lower ordered systems. 相似文献