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61.
We report that specific anions (of sodium salts) added to aqueous phases at molar concentrations can trigger rapid, orientational ordering transitions in water-immiscible, thermotropic liquid crystals (LCs; e.g., nematic phase of 4'-pentyl-4-cyanobiphenyl, 5CB) contacting the aqueous phases. Anions classified as chaotropic, specifically iodide, perchlorate, and thiocyanate, cause 5CB to undergo continuous, concentration-dependent transitions from planar to homeotropic (perpendicular) orientations at LC-aqueous interfaces within 20 s of addition of the anions. In contrast, anions classified as relatively more kosmotropic in nature (fluoride, sulfate, phosphate, acetate, chloride, nitrate, bromide, and chlorate) do not perturb the LC orientation from that observed without added salts (i.e., planar orientation). Surface pressure-area isotherms of Langmuir films of 5CB supported on aqueous salt solutions reveal ion-specific effects ranking in a manner similar to the LC ordering transitions. Specifically, chaotropic salts stabilized monolayers of 5CB to higher surface pressures and areal densities (12.6 mN/m at 27 ?(2)/molecule for NaClO(4)) and thus smaller molecular tilt angles (30° from the surface normal for NaClO(4)) than kosmotropic salts (5.0 mN/m at 38 ?(2)/molecule with a corresponding tilt angle of 53° for NaCl). These results and others reported herein suggest that anion-specific interactions with 5CB monolayers lead to bulk LC ordering transitions. Support for the proposition that these ion-specific interactions involve the nitrile group was obtained by using a second LC with nitrile groups (E7; ion-specific effects similar to 5CB were observed) and a third LC with fluorine-substituted aromatic groups (TL205; weak dipole and no ion-specific effects were measured). Finally, we also establish that anion-induced orientational transitions in micrometer-thick LC films involve a change in the easy axis of the LC. Overall, these results provide new insights into ionic phenomena occurring at LC-aqueous interfaces, and reveal that the long-range ordering of LC oils can amplify ion-specific interactions at these interfaces into macroscopic ordering transitions.  相似文献   
62.
Enveloped viruses fuse with cells to transfer their genetic materials and infect the host cell. Fusion requires deformation of both viral and cellular membranes. Since the rigidity of viral membrane is a key factor in their infectivity, studying the rigidity of viral particles is of great significance in understating viral infection. In this paper, a nanopore is used as a single molecule sensor to characterize the deformation of pseudo‐type human immunodeficiency virus type 1 at sub‐micron scale. Non‐infective immature viruses were found to be more rigid than infective mature viruses. In addition, the effects of cholesterol and membrane proteins on the mechanical properties of mature viruses were investigated by chemically modifying the membranes. Furthermore, the deformability of single virus particles was analyzed through a recapturing technique, where the same virus was analyzed twice. The findings demonstrate the ability of nanopore resistive pulse sensing to characterize the deformation of a single virus as opposed to average ensemble measurements.  相似文献   
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In this paper, we analytically investigate the noncommutative effects of a charged black hole on holographic superconductors in the probe limit. The effects of charge of the black hole is investigated in our study. Employing the Sturm–Liouville eigenvalue method, the relation between the critical temperature and charge density is analytically investigated. The condensation operator is then computed. It is observed that condensate gets harder to form for large values of charge of the black hole.  相似文献   
65.
As an extension of intuitionistic fuzzy sets, the theory of picture fuzzy sets not only deals with the degrees of rejection and acceptance but also considers the degree of refusal during a decision-making process; therefore, by incorporating this competency of picture fuzzy sets, the goal of this study is to propose a novel hybrid model called picture fuzzy soft expert sets by combining picture fuzzy sets with soft expert sets for dealing with uncertainties in different real-world group decision-making problems. The proposed hybrid model is a more generalized form of intuitionistic fuzzy soft expert sets. Some novel desirable properties of the proposed model, namely, subset, equality, complement, union and intersection, are investigated together with their corresponding examples. Two well-known operations AND and OR are also studied for the developed model. Further, a decision-making method supporting by an algorithmic format under the proposed approach is presented. Moreover, an illustrative application is provided for its better demonstration, which is subjected to the selection of a suitable company of virtual reality devices. Finally, a comparison of the initiated method is explored with some existing models, including intuitionistic fuzzy soft expert sets.  相似文献   
66.
Two new conjugated dendrimers bearing a tetraphenylethylene moiety as dendrons and triphenylamine as a core have been synthesized through a convergent synthetic strategy using threefold Heck/threefold Sonogashira coupling reaction. These dendrimers showed excellent solubility in common organic solvents and emit light in the blue and violet regions.  相似文献   
67.
Azobenzene dendrimer 2 was synthesized from a known dendritic azo-tetracarboxylic acid and a dendritic amine incorporating 1,2-isopropylidenefuranose rings, and its trans-cis isomerization was studied by UV-vis absorption spectroscopy.  相似文献   
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The (n, 2n) cross sections at neutron energies between 14.9 and 17.0 MeV have been measured for 85Rb, 87Rb and 144Sm by the mixed-powder method and γ-ray detection by a Ge(Li) spectrometer. Using the 27Al(n, α)24Na reaction for monitoring, the measured cross sections were (in mb): 85Rb(n, 2n)84(m+g)Rb, 1125±141, 1177±148 and 1235±162 at 15.0±0.4 MeV, 16.2±0.7 MeV and 17.0±0.9 MeV, respectively; 85Rb(n, 2n)84mRb, 662±83, 688±87 and 765±99 at 15.0±0.4 MeV, 16.2±0.7 MeV and 17.0±0.9 MeV, respectively; 87Rb(n, 2n)86(m+g)Rb, 1336±168 and 1301±162 at 15.0±0.4 MeV and 16.2±0.7 MeV respectively; 144Sm(n, 2n)143(m+g)Sm, 1202±130, 1300±141, 1516±179 and 1514±179 at 14.9±0.3 MeV, 15.5±0.3 MeV, 16.4±0.5 MeV and 16.7±0.2 MeV, respectively. The measured values are compared with the statistical model calculations of Pearlstein.  相似文献   
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