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991.
Ayako Itaba 《代数通讯》2013,41(1):404-415
We calculate the dimensions of the Hochschild cohomology groups of a self-injective special biserial algebra Λ s obtained by a circular quiver with double arrows. Moreover, we give a presentation of the Hochschild cohomology ring modulo nilpotence of Λ s by generators and relations. This result shows that the Hochschild cohomology ring modulo nilpotence of Λ s is finitely generated as an algebra.  相似文献   
992.
Abstract

Gaseous ethanol, acetaldehyde, 1-propanol, 2-propanol and acetone at pressures of 2 × 10?5 to 5 × 10?4 torr were irradiated with electrons of energies 0-1000 eV. The visible-region fluorescence of the excited fragments was then measured. Studies included pressure dependence, electron energy dependence, threshold energy measurements, and excitation curve measurements. The aim of the research was to ascertain if molecules of similar structure could be differentiated by their spectra.  相似文献   
993.
Abstract

The ternary sulfide Ag7TaS6 displays high Ag-ion conductivity at ambient temperature, and the framework TaS6 and Ag ions can be respectively regarded as the host structure and guest ions. Two low-temperature phases, i.e. Ag7TaS6 II and Ag7TaS6 III, were found. The Rietveld analysis of Ag7TaS6 II has been performed based on the X-ray data measured at 240K using a wave length 0.64997Å by a high-resolution powder diffraction instrument combined with the beam line BMlB at the European Synchrotron Radiation Facilities. Smooth convergence has been obtained (RWP=0.066), and the crystal structure was described based on a space group Pn with monoclinic lattice constants a=7.4462, b=7.4013, c=10.5296Å and β=90.069°. The narrow widths of reflections even at high angle have made possible the analysis of individual thermal parameters for Ag ions. In Ag7TaS6 II, Ag-Ag linkage rather than Ag-S coordination seem to affect the thermal parameters of Ag ions. The guest-guest interaction can be important for mobility of guest ions in the ionic conductor.  相似文献   
994.
Enhancement of sensitivity in solid state (15)N NMR by indirect detection through (1)H NMR signals under high-speed magic angle spinning and high-field conditions is demonstrated experimentally on two (15)N-labeled peptides, polycrystalline AlaGlyGly and the helix-forming, 17-residue peptide MB(i + 4)EK in lyophilized form. Sensitivity enhancement factors ranging from 2.0 to 3.2 are observed experimentally, depending on the (15)N and (1)H linewidths and polarization transfer efficiencies. The (1)H-detected two-dimensional (1)H/(15)N correlation spectrum of AlaGlyGly illustrates the possibility of increased spectral resolution and resonance assignments in indirectly detected experiments, in addition to the sensitivity enhancement.  相似文献   
995.
A macroporous silica-based supramolecular recognition absorbent (Calix[4]?+?Dodecanol)/SiO2?CP, was prepared by successive impregnation and fixing the 1,3-[(2,4-diethylheptylethoxy)oxy]-2,4-crown-6-Calix[4]arene (Calix[4]arene-R14) and its molecule modifier 1-Dodecanol onto SiO2 silica-based polymer support. The characterization of (Calix[4]?+?Dodecanol)/SiO2?CP was examined by thermal gravimetry and differential thermal analysis and electron probe microanalysis. Relatively large separation factors of Cs and other metal ions (?? Cs/M n+ ) above 60 were obtained in the presence of 3?M HNO3. The adsorption data of Cs(I) fitted well with Langmuir isotherm and the maximum adsorption capacity was estimated to be 0.19?mmol?g?1. The Cs(I) in 3?M HNO3 were also effectively adsorption on (Calix[4]?+?Dodecanol)/SiO2?CP in the column operation, and the loaded Cs(I) was successfully eluted with an eluent of H2O. The column packed with (Calix[4]?+?Dodecanol)/SiO2?CP had excellent reusability after three cycles.  相似文献   
996.
Solid-phase peptide synthesis (SPPS) is a widely used technique in biology and chemistry. However, the synthesis yield in SPPS often drops drastically for longer amino acid sequences, presumably because of the occurrence of incomplete coupling reactions. The underlying cause for this problem is hypothesized to be a sequence-dependent propensity to form secondary structures through protein aggregation. However, few methods are available to study the site-specific structure of proteins or long peptides that are anchored to the solid support used in SPPS. This study presents a novel solid-state NMR (SSNMR) approach to examine protein structure in the course of SPPS. As a useful benchmark, we describe the site-specific SSNMR structural characterization of the 40-residue Alzheimer's β-amyloid (Aβ) peptide during SPPS. Our 2D (13)C/(13)C correlation SSNMR data on Aβ(1-40) bound to a resin support demonstrated that Aβ underwent excessive misfolding into a highly ordered β-strand structure across the entire amino acid sequence during SPPS. This approach is likely to be applicable to a wide range of peptides/proteins bound to the solid support that are synthesized through SPPS.  相似文献   
997.
W Hu  KS Ishii  Q Fan  AT Ohta 《Lab on a chip》2012,12(19):3821-3826
A novel hydrogel microrobot made of poly(ethylene glycol) diacrylate (PEGDA) is reported. This disk-shaped microrobot is optothermally actuated by laser-induced bubbles. A pulsed laser is used to smoothly actuate an 80-μm-diameter bubble microrobot at up to 320 μm s(-1). A single microrobot or a pair of microrobots working in cooperation were used to assemble 20-μm-diameter polystyrene beads into different patterns. The microrobots were also used to assemble patterns made of single yeast cells and cell-laden agarose microgels. The patterned yeast cells and cell-laden microgels were cultured, and the cells successfully multiplied.  相似文献   
998.
A chemical model of deterioration of a bulk heterojunction organic solar cell containing a photooxidized product of 1,4-bis(dimethylphenylsilylmethyl)[60]fullerene suggests that molecular oxygen degrades device performance by two mechanisms.  相似文献   
999.
Seven phenolic compounds, including a new phenylethanoid glycoside, were isolated from the ethyl acetate fraction of an aqueous ethanol extract of Plantago Herb (whole part of Plantago asiatica L.), which showed significant antioxidative activity. The new compound was characterized as 2-(3,4-dihydroxyphenyl)ethyl 3-O-β-D-allopyranosyl-6-O-caffeoyl-β-D-glucopyranoside on the basis of spectral and chemical evidence, and its antioxidant activity was comparable to that of tea catechins.  相似文献   
1000.
This paper considers several probability maximization models for multi-scenario portfolio selection problems in the case that future returns in possible scenarios are multi-dimensional random variables. In order to consider occurrence probabilities and decision makers’ predictions with respect to all scenarios, a portfolio selection problem setting a weight with flexibility to each scenario is proposed. Furthermore, by introducing aspiration levels to occurrence probabilities or future target profit and maximizing the minimum aspiration level, a robust portfolio selection problem is considered. Since these problems are formulated as stochastic programming problems due to the inclusion of random variables, they are transformed into deterministic equivalent problems introducing chance constraints based on the stochastic programming approach. Then, using a relation between the variance and absolute deviation of random variables, our proposed models are transformed into linear programming problems and efficient solution methods are developed to obtain the global optimal solution. Furthermore, a numerical example of a portfolio selection problem is provided to compare our proposed models with the basic model.  相似文献   
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