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931.
932.
933.
Background
To better understand the molecular interactions of Bt toxins with non-target insects, we have examined the real-time binding specificity and affinity of Cry1 toxins to native silkworm (Bombyx mori) midgut receptors. Previous studies on B. mori receptors utilized brush border membrane vesicles or purifed receptors in blot-type assays. 相似文献934.
Barbara A. Fir Hlne P. A. Mercier Jeremy C. P. Sanders David A. Dixon Gary J. Schrobilgen 《Journal of fluorine chemistry》2001,110(2):89-107
The XeOSeF5+ cation has been synthesized for the first time and characterized in solution by 19F, 77Se and 129Xe NMR spectroscopy and in the solid state by X-ray crystallography and Raman spectroscopy with AsF6− as its counter anion. The X-ray crystal structures of the tellurium analogue and of the Xe(OChF5)2 derivatives have also been determined: [XeOChF5][AsF6] crystallize in tetragonal systems, P4/n, a=6.1356(1) Å, c=13.8232(2) Å, V=520.383(14) Å3, Z=2 and R1=0.0453 at −60°C (Te) and a=6.1195(7) Å, c=13.0315(2) Å, V=488.01(8) Å3, Z=2 and R1=0.0730 at −113°C (Se); Xe(OTeF5)2 crystallizes in a monoclinic system, P21/c, a=10.289(2) Å, b=9.605(2) Å, c=10.478(2) Å, β=106.599(4)°, V=992.3(3) Å3, Z=4 and R1=0.0680 at −127°C; Xe(OSeF5)2 crystallizes in a triclinic system,
, a=8.3859(6) Å, c=12.0355(13) Å, V=732.98(11) Å3, Z=3 and R1=0.0504 at −45°C. The energy minimized geometries and vibrational frequencies of the XeOChF5+ cations and Xe(OChF5)2 were calculated using density functional theory, allowing for definitive assignments of their experimental vibrational spectra. 相似文献
935.
Dr. Jeremy A. Bau Prof. Magnus Rueping 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(35):8960-8965
Hydrogen storage in the form of intermediate artificial fuels such as methanol is important for future chemical and energy applications, and the electrochemical regeneration of hydrogen from methanol is thermodynamically favorable compared to direct water splitting. However, CO produced from methanol oxidation can adsorb to H2-evolution catalysts and drastically reduce activity. In this study, we explore the origins of CO immunity in Mo-containing H2-evolution catalysts. Unlike conventional catalysts such as Pt or Ni, Mo-based catalysts display remarkable immunity to CO poisoning. The origin of this behavior in NiMo appears to arise from the apparent inability of CO to bind Mo under electrocatalytic conditions, with mechanistic consequences for the H2-evolution reaction (HER) in these systems. This specific property of Mo-based HER catalysts makes them ideal in environments where poisons might be present. 相似文献
936.
937.
We study the combinatorics of two classes of basic hypergeometric series. We first show that these series are the generating functions for certain overpartition pairs defined by frequency conditions on the parts. We then show that when specialized these series are also the generating functions for overpartition pairs with bounded successive ranks, overpartition pairs with conditions on their Durfee dissection, as well as certain lattice paths. When further specialized, the series become infinite products, leading to numerous identities for partitions, overpartitions, and overpartition pairs. 相似文献
938.
939.
Jeremy J. Intemann Jared F. Mike Min Cai Charles A. Barnes Teng Xiao Robert A. Roggers Joseph Shinar Ruth Shinar Malika Jeffries‐EL 《Journal of polymer science. Part A, Polymer chemistry》2013,51(4):916-923
A series of vinylene‐linked copolymers based on electron‐deficient benzobisthiazole and electron‐rich fluorene moieties were synthesized via Horner–Wadsworth–Emmons polymerization. Three different polymers P1 , P2 , and P3 , were prepared bearing octyl, 3,7‐dimethyloctyl, and 2‐(2‐ethoxy)ethoxyethyl side chains, respectively. The polymers all possessed moderate molecular weights, good solubility in aprotic organic solvents, and high fluorescence quantum efficiencies in dilute solutions. P2 , which bore branched 3,7‐dimethyloctyl side chains, exhibited better solubility than the other polymers, but also exhibited the lowest thermal decomposition temperature of all polymers. Overall, the impact of the side chains on the polymers optical properties in solution was negligible as all three polymers gave similar absorption and emission spectra in both solution and film. Guest‐host light‐emitting diodes using dilute blends of the polymers in a poly(N‐vinylcarbazole) host gave blue‐green emission with P2 exhibiting the highest luminous efficiency, 0.61 Cd/A at ~500 nm. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献
940.
Evan M. White Jeremy Yatvin Joe B. Grubbs III Jenna A. Bilbrey Jason Locklin 《Journal of polymer science. Part A, Polymer chemistry》2013,51(14):1084-1099
This review highlights recent developments in the field of stimuli-responsive hydrogels, focusing primarily on thin films, with a thickness range between 100 nm to 10 μm. The theory and dynamics of hydrogel swelling is reviewed, followed by specific applications. Gels are classified based on the active stimulus—mechanical, chemical, pH, heat, and light—and fabrication methods, design constraints, and novel stimuli-responses are discussed. Often, these materials display large physiochemical reactions to a relatively small stimulus. Noteworthy materials larger than 10 μm, but with response times on the order of seconds to minutes are also discussed. Hydrogels have the potential to advance the fields of medicine and polymer science as useful substrates for “smart” devices. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2013, 51, 1084–1099 相似文献