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501.
502.
Recently a BPS Alice string has been found in a \(U(1)\times SO(3)\) gauge theory coupled with three charged complex scalar fields in the triplet representation (in JHEP 1709:046 arXiv:1703.08971 [hep-th], 2017). It is a half BPS state preserving a half of the supercharges when embedded into a supersymmetric gauge theory. In this paper, we study zero modes of a BPS Alice string. After presenting U(1) and translational zero modes, we construct the effective action of these modes. In contrast to a previous analysis of the conventional Alice string for which only large distance behaviors are known, we can exactly perform a calculation in the full space thanks to the BPS properties.  相似文献   
503.
Organostannoxane-based multiredox assemblies containing ferrocenyl peripheries have been readily synthesized by a simple one-pot synthesis, either by a solution method or by room-temperature solid-state synthesis, in nearly quantitative yields. The number of ferrocenyl units in the multiredox assembly is readily varied by stoichiometric control as well as by the choice of the organotin precursors. Thus, the reaction of the diorganotin oxides, R2SnO (R = Ph, nBu and tBu) with ferrocene carboxylic acid affords tetra-, di-, and mononuclear derivatives [{Ph2Sn[OC(O)Fc]2}2] (1), [{[nBu2SnOC(O)Fc]2O}2] (2), [nBu2Sn{OC(O)Fc}2] (3), [{tBu2Sn(OH)OC(O)Fc}2] (4), and [tBu2Sn{OC(O)Fc}2] (5) (Fc = eta(5)C5H4-Fe-eta(5)C5H5). The reaction of triorganotin oxides, R3SnOSnR3 (R = nBu and Ph) with ferrocene carboxylic acid leads to the formation of the mono-nuclear derivatives [Ph3SnOC(O)Fc] (6) and [{nBu3SnOC(O)Fc}(n)] (7). Molecular structures of the compounds 1-4 and 6 have been determined by single-crystal X-ray analysis. The molecular structure of compound 1 is new among organotin carboxylates. In this compound, ferrocenyl carboxylates are involved in both chelating and bridging coordination modes to the tin atoms to form an eight-membered cyclic structure. In all of these compounds, the acidic protons of the cyclopentadienyl groups are hydrogen bonded to the carboxylate oxygens (C-HO) to form rich supramolecular assemblies. In addition to this, pi-pi, T-shaped, L-shaped, and side-to-face stacking interactions involving ferrocenyl groups also occur. Compound 6 shows an interesting and novel intermolecular CO2-pi stacking interaction. Electrochemical analysis of the compounds 1-4, 6, and 7 shows a single, quasi-reversible oxidation peak corresponding to the simultaneous oxidation of four, two, and one ferrocenyl substituents, respectively. Compound 5 shows two quasi-reversible oxidation peaks. This is attributed to the positional difference among the ferrocenyl substituents on the tin atom. Additionally, while compounds 2 and 4 are electrochemically quite robust and do not decompose even after ten continuous CV cycles, compounds 1, and 3, 5-7 start to show decomposition after five cycles.  相似文献   
504.
A novel linear trinuclear magnesium complex (P(S)[N(CH3)N=CHC6H4-o-O]3)2Mg3 was prepared by the reaction of P(S)[N(CH3))N=CHC6H4-o-OH]3 with MgCl2 x 6H2O in the presence of triethylamine. The trinuclear magnesium complex is fluorescent in solution as well as in the solid-state.  相似文献   
505.
Apolar, neutral peptides have been shown to ionize extremely well under the conditions used for electrospray ionization mass spectrometry (ESIMS). Peptides for which the conformations have been independently determined in solution and in crystals have been examined by ESIMS. Studies of peptide helices ranging from 7 to 18 residues reveal that shorter helices yield exclusively singly charged ions, while in larger helices multiply charged species are detectable. Multiple sites for protonation/metallation are introduced in the helix by proline insertion or by changing the chirality in the residue. The preferred site of cation binding to helices may be the C-terminus end, where three free CO groups are available for chelation. Ab initio and DFT calculations at several levels have been carried out for the binding of H+, Li+, Na+, and K+ to CHO-(Gly)3)-OMe. The results reveal that metallation in helices is favoured by chelation to carbonyl groups at the C-terminus, while protonation involved two carbonyl groups and thus favour a 10-membered cyclic hydrogen-bonded structure. In -strands, metallation/protonation occurs at isolated carbonyl groups. Collision induced fragmentation of hydrophobic peptides under ESI conditions reveals that helix fragmentation occurs predominantly from the C-terminus, while in -hairpins cleavage occurs simultaneously at multiple sites.  相似文献   
506.
Rotation-free transmission measurements governed by ground-state recovery of coumarin 102, coumarin 138 and coumarin 339 dyes in ethanol solutions were performed for the first time by pump-probe technique using 35 ps pulses of Nd:YAG laser at 355 nm. Recovery of absorption is characterized by simple exponential behaviour with relaxation times of 4.0, 3.7 and 3.0 ns respectively for C 102, C 138 and C 339. These values are comparable to the lifetimes of the first excited singlet states.  相似文献   
507.
508.
The thermal conductivity of thin films of superconducting Pb-3 at. % In alloy is measured in the normal and the superconducting states. The ratio of the electronic thermal conductivity in the superconducting state Kes to that in the normal state Ken is found to be in good agreement with the Bardeen, Rickayzen and Tewordt theory with 2?O = 4.36 kTc.  相似文献   
509.
510.
A new structural form of tin in a double O-capped cluster   总被引:1,自引:0,他引:1  
A novel hexameric organooxotin cage [{(n-BuSn)3(PhO)3O}2{HPO3}4] 1 has been assembled by the reaction of [n-BuSnO(OH)] with (PhO)2P(O)H. The structure of 1 consists of two O-capped Sn3 clusters that are attached to each other by four bridging tripodal [HPO3]2- ligands.  相似文献   
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