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131.
We construct two families of distance-regular graphs, namely the subgraph of the dual polar graph of type B 3(q) induced on the vertices far from a fixed point, and the subgraph of the dual polar graph of type D 4(q) induced on the vertices far from a fixed edge. The latter is the extended bipartite double of the former.  相似文献   
132.
Time-resolved vibrational spectroscopy is used to investigate the inter-component motion of an ultraviolet-triggered two-station molecular shuttle. The operation cycle of this molecular shuttle involves several intermediate species, which are observable in the amide I and amide II regions of the mid-IR spectrum. Using ab initio calculations on specific parts of the rotaxane, and by comparing the transient spectra of the normal rotaxane with that of the N-deuterated version, we can assign the observed vibrational modes of each species occurring during the shuttling cycle in an unambiguous way. The complete time- and frequency-dependent data set is analyzed using singular value decomposition (SVD). Using a kinetic model to describe the time-dependent concentrations of the transient species, we derive the absorption spectra associated with each stage in the operation cycle of the molecular shuttle, including the recombination of the charged species.  相似文献   
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134.
The incorporation of a single beta-aminoethane sulfonyl amide moiety in a highly amyloidogenic peptide sequence resulted in a complete loss of amyloid fibril formation. Instead, supramolecular folding morphologies were observed. Subsequent chemoselective N-alkylation of the sulfonamide resulted in amphiphilic peptide-based hydrogelators. It was found that variation of merely the alkyl chain induced a dramatic variation in aggregation motifs such as helical ribbons and tapes, ribbons progressing to closed tubes, twisted lamellar sheets and entangled/branched fibers.  相似文献   
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137.
The search of materials with efficient optically stimulated luminescence (OSL) properties and a high hydrogen content for fast neutron dosimetry has led to the development of Tl+-doped ammonium salts (NH4)2SiF6 and (NH4)2BeF4. Preliminary OSL studies have shown that the OSL in (NH4)2SiF6:Tl+ and (NH4)2BeF4:Tl+is efficient. In order to optimise the OSL emission and its detection, the identification of the luminescent centres in the OSL process is necessary. This study focuses on the identification of the luminescent centres associated with Tl+ based on optical studies in the vacuum UV (VUV) at different temperatures.  相似文献   
138.
We determine the spectra of the finite Coxeter graphs defined by a terminal node of the Coxeter diagram, and the spectra of their thick equivalents.  相似文献   
139.
We conjecturethat all locally Paley graphs are known. For locally Paley(p)with p < 100000 this is true.  相似文献   
140.
The concept of proteasome inhibition ranks among the latest achievements in the treatment of blood cancer and represents a promising strategy for modulating autoimmune diseases. In this study, we describe peptidic sulfonyl fluoride inhibitors that selectively block the catalytic β5 subunit of the immunoproteasome by inducing only marginal cytotoxic effects. Structural and mass spectrometric analyses revealed a novel reaction mechanism involving polarity inversion and irreversible crosslinking of the proteasomal active site. We thus identified the sulfonyl fluoride headgroup for the development and optimization of immunoproteasome selective compounds and their possible application in autoimmune disorders.  相似文献   
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