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111.
At a weight ratio of n‐C5H11OH/H2O=50/50, when the total content of sodium dodecyl sulfate (SDS) was less than 6.0%, the ternary mixture of SDS/n‐C5H11OH/H2O coexisted in two immiscible microemulsions. The distribution and transfer of gatifloxacin (GTFX) between the two phases were studied using UV‐Vis and electrochemistry AC impedance spectra. The results show that GTFX transferred from the upper phase (W/O) to the lower phase (O/W or bicontinuous microemulsion), but a small amount of SDS transferred from the lower phase to the upper phase correspondingly with the increase of the total SDS content at a total GTFX concentration of 1.0×10?5 mol/L. The addition of GTFX did not change the structures of the two different phases fundamentally, but resulted in the transfer and redistribution of GTFX and SDS, so the electric properties of the system were changed correspondingly. 相似文献
112.
113.
Wanjun Gong Xiran Yang Peter Y. Zavalij Prof. Lyle Isaacs Dr. Zhiyong Zhao Prof. Simin Liu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(49):17612-17618
As the host possessing the largest cavity in the cucurbit[n]uril (CB[n]) family, CB[10] has previously displayed unusual recognition and assembly properties with guests but much remains to be explored. Herein, we present the recognition properties of CB[10] toward a series of bipyridinium guests including the tetracationic cyclophane known as blue box along with electron‐rich guests and detail the influence of encapsulation on the charge‐transfer interactions between guests. For the mono‐bipyridinium guest (methylviologen, MV 2+), CB[10] not only forms 1:1 and 1:2 inclusion complexes, but also enhances the charge‐transfer interactions between methylviologen and dihydroxynaphthalene ( HN ) by mainly forming the 1:2:1 packed “sandwich” complex (CB[10] ? 2 MV 2+ ?HN ). For guest 1 with two bipyridinium units, an interesting conformational switching from linear to “U” shape is observed by adding catechol to the solution of CB[10] and the guest. For the tetracationic cyclophane‐blue box, CB[10] forms a stable 1:1 inclusion complex; the two bipyridinium units tilt inside the cavity of CB[10] according to the X‐ray crystal structure. Finally, a supramolecular “Russian doll” was built up by threading a guest through the cavities of both blue box and CB[10]. 相似文献
114.
含Dawson结构杂多钨磷(砷)酸电荷转移配合物的合成、结构与性质 总被引:6,自引:0,他引:6
近年来,有机多金属氧酸盐电荷转移配合物由于有特殊的光、电、磁性质在催化、功能材料及药物化学等领域受到研究者的广泛关注[1]。自从1988年法国的L.Ouahab[2]首次报道(TTF)6PW12O40(Et4N)2的合成以来,已见报道的多金属氧酸盐仅限于AndersonEvanse、lindquist和Keggin结构的多阴离子,对它们功能性质的系统研究也未见文献报道。为了研究阴离子的大小和形状对标题化合物功能性质的影响,作者在以前工作的基础上[3,4],首次以Dawson结构杂多钨磷(砷)… 相似文献
115.
IntroductionReactivityratioscanofferthemessageofrelativereactivityofcomonomers.TWomonomerreactivityratioscanbeacquiredfromtheend-groupmodelproposedbyMayoandLewis,howevef,thereareonlyapparentreactivityratiosavailablefromthiskineticmodelwhencharge-transfercomplex(CTC)participatesinthecopolymerization.Therefore,thecopolymeriZationinwhichCTCexistsisworthyoffurtherresearch.Sofar,therearethreekineticmodelsofcopolymerizationwiththeparticipationofCTCinall,namely,SeinerandLittmodel',Shirotamodel… 相似文献
116.
A method was developed for the synthesis of unsymmetrical strong electron donors. 4,5-Dimethyl-1,3-dithiolylidene(4-dimethylaminophenyl)acetonitrile was obtained, and its properties were investigated by electrochemica, spectroscopic, and quantum-chemical methods.Riga Technical University, Riga, Latvia. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 22–25, January, 2000. 相似文献
117.
M. Levitskii A. Zhdanov O. Tshegolikhina R. Stukan A. Knizhnik A. Kolbanovskii 《Molecular Crystals and Liquid Crystals》2013,570(1):523-526
The idea of designing ferromagnets chemically boils down to uniting paramagnetic atoms by means of a chemical reaction and “turning on” positive exchange interaction between them, which aligns the atoms'electron spins into ferromagnetic order. This general idea can be tested using organometallic polymers with metal paramagnetic atoms in the polymer chain. The metal atoms are isolated by organic fragments and are not bound by exchange interaction. Two ways can be used to turn on the exchange. The first is to remove the isolating fragments between the metal atoms or to replace them by electron-conductive fragments which allow the exchange interaction. The second is to build new molecular bridges able to turn it on. 相似文献
118.
The new compound 1-(2-methoxyphenyl)piperazinium chloranilate (MPP.CA) was synthesized and studied by the single crystal X-ray diffraction method. Its structure was confirmed by infrared spectroscopy. The crystal structure consists of ribbons of chloranilate anions and 1-(2-methoxyphenyl)piperazinium cations linked together by NH…O hydrogen bonds. Two protons are transferred from a chloranilic acid molecule to the nitrogen of the piperazine in this structure. Measurements of AC conductivity as a function of frequency at different temperatures indicated the hopping conduction mechanism; in addition, the variation of dielectric constant as a function of T confirmed the transition phase indicated by the differential scanning calorimetry (DSC). The physico-chemical properties, UV-Vis, DSC and dielectric properties are described. Hirshfeld surface analyzes all the intermolecular interactions involved within the structure, which are important to stabilize the structure. 相似文献
119.
120.
K. Sekimoto M. Takayama 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2008,50(3):297-305
The dependence of negative ion formation on the inhomogeneous electric field
strength in atmospheric pressure negative corona discharge with
point-to-plane electrodes has been described. The distribution of negative
ions HO-, NOx
- and COx
- and their abundances on the
plane electrode was obtained with a mass spectrometer. The ion distribution
on the plane was divided into two regions, the center region on the needle
axis and peripheral region occurring the dominant NOx
- and
COx
- ions and HO- ion, respectively. The calculated electric
field strength in inhomogeneous electric field established on the needle tip
surface suggested that the abundant formation of NOx
- and
COx
- ions and HO- ion is attributed to the high field
strength at the tip apex region over 108 Vm-1 and the low field
strength at the tip peripheral region of the order of 107 Vm-1,
respectively. The formation of HO-, NOx
- and COx
-
has been discussed from the standpoint of negative ion evolution based on
the thermochemical reaction and the kinetic energy of electron emitted from
the needle tip. 相似文献