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排序方式: 共有123条查询结果,搜索用时 31 毫秒
31.
Clarke ML Ellis D Mason KL Orpen AG Pringle PG Wingad RL Zaher DA Baker RT 《Dalton transactions (Cambridge, England : 2003)》2005,(7):1294-1300
The fluoroaryl phosphines P{C6H3(CF3)2-3,5}3 (La) and P(C6F5)3 (Lb) form the complexes trans-[MCl2(La)2] and trans-[MCl2(Lb)2](M = Pd or Pt) which have been isolated and fully characterised. 31P NMR studies of competition experiments show that the stability of trans-[PdCl2L2] is in the order L = Lb< La 相似文献
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Dr. Colin S. M. Kang Dr. Oliver E. Hutt Prof. Jennifer M. Pringle 《Chemphyschem》2022,23(13):e202200115
The implementation of next-generation batteries requires the development of safe, compatible electrolytes that are stable and do not cause safety problems. The difluoro(oxalato)borate ([DFOB]−) anion has been used as an electrolyte additive to aid with stability, but such an approach has most commonly been carried out using flammable solvent electrolytes. As an alternative approach, utilisation of the [DFOB]− anion to make ionic liquids (ILs) or Organic Ionic Plastic Crystals (OIPCs) allows the advantageous properties of ILs or OIPCs, such as higher thermal stability and non-volatility, combined with the benefits of the [DFOB]− anion. Here, we report the synthesis of new [DFOB]−-based ILs paired with triethylmethylphosphonium [P1222]+, and diethylisobutylmethylphosphonium [P122i4]+. We also report the first OIPCs containing the [DFOB]− anion, formed by combination with the 1-ethyl-1-methylpyrrolidinium [C2mpyr]+ cation, and the triethylmethylammonium [N1222]+ cation. The traditional synthetic route using halide starting materials has been successfully replaced by a halide-free tosylate-based synthetic route that is advantageous for a purer, halide free product. The synthesised [DFOB]−-based salts exhibit good thermal stability, while the ILs display relatively high ionic conductivity. Thus, the new [DFOB]−-based electrolytes show promise for further investigation as battery electrolytes both in liquid and solid-state form. 相似文献
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Baber A de Vries JG Orpen AG Pringle PG von der Luehe K 《Dalton transactions (Cambridge, England : 2003)》2006,(40):4821-4828
The new unsymmetrical, optically active ligands 1,2-C(2)H(4)(PPh(2))(2'R,5'R-2',5'-dimethylphospholanyl) (L(a)) and 1,3-C(3)H(6)(PPh(2))(2'R,5'R-2',5'-dimethylphospholanyl) (L(b)) form complexes of the type [Rh(L)(cyclooctadiene)][BF(4)] where L = L(a) (1a) or L(b) (1b), [PtCl(2)(L)] where L = L(a) (2a) or L(b) (2b) and [PdCl(2)(L)] where L = L(a) (3a) or Lb (3b). The crystal structures of 2a and 2b show the chelate ligand backbones adopt delta-twist and flattened chair conformations respectively. Asymmetric hydrogenation of enamides and dehydroaminoesters using 1a and 1b as catalysts show that the ethylene-backboned diphosphine L(a) gives a more efficient catalyst in terms of asymmetric induction than the propylene-backboned analogue L(b). The greatest enantioselectivities were obtained with 1a and enamide substrates with ees up to 91%. Substrate-induced conformational changes in the Rh-diphosphine chelates are proposed to explain some of the ees observed in the hydrogenation of enamides. 相似文献
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ER Badman GE Patterson JM Wells RE Santini RG Cooks 《Journal of mass spectrometry : JMS》1999,34(8):889-894
Dual-detector differential non-destructive Fourier transform detection in a quadrupole ion trap is shown to improve signal intensity and reduce noise compared with spectra recorded using a single detector. A larger area detector in each end-cap electrode is machined to fit its hyperbolic shape and so minimize field imperfections on the z-axis. Argon, acetophenone and bromobenzene spectra were recorded to allow a comparison between single- and dual-detector (differential) modes of detection and to demonstrate the improvement achieved with differential detection. Copyright 1999 John Wiley & Sons, Ltd. 相似文献
36.
Polubarinova-Kochina's analytical differential equation methodis used to determine the pseudo-steady-state solution to problemsinvolving the freezing (solidification) of wedges of liquidwhich are initially at their fusion temperature. In particular,we consider four distinct problems for wedges which are: freezingwith the same constant boundary temperature, freezing with thesame constant boundary heat fluxes, freezing with distinct constantboundary temperatures and freezing with distinct constant fluxesat the boundaries. For the last two problems, a Heun's differentialequation with an unknown singularity is derived, which in bothcases admits a particularly elegant simple solution for thespecial case when the wedge angle is . The moving boundariesobtained are shown pictorially. 相似文献
37.
Alves GA Amato S Anjos JC Appel JA Astorga J Bernard T Bracker SB Cremaldi LM Darling CL Dixon RL Errede D Gay C Green DR Jedicke R Karchin PE Kwan S Lueking LJ de Mello Neto JR Metheny J Milburn RH de Miranda JM da Motta Filho H Napier A Passmore D Rafatian A dos Reis AC Ross WR Santoro AF Sheaff M Souza MH Spalding WJ Stoughton C Streetman ME Summers DJ Takach SF Wallace A Wu Z 《Physical review letters》1994,72(6):812-815
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