Treatment of (E)-3-(4-azidophenyl)- and (E)-3-(2-azidophenyl)acrylic acid with N-halosuccinimides in the presence of LiOAc afforded high yields of phenylazides containing (E)-2-halovinyl group. The latter were transformed to different phenyl-1,2,3-triazoles bearing (E)-halovinyl group by the CuI-catalyzed reaction of 1,3-dipolar cycloaddition. 相似文献
A new coordination polymer, [Ca(AIP)(Phen)(H2O)2] · Phen · H2O (H2AIP = 5-aminoisophthalic acid, Phen = 1,10-phenanthroline), was synthesized using the water bath method and characterized by elemental analyses and single crystal X-ray diffraction, which revealed that I has an interesting 1D chain structure. The adjacent chains are further connected together via the π-π packing interactions and hydrogen bonding interactions. 相似文献
Ceria‐zirconia composites at different molar ratios were synthesized. Several methods were used to characterize these composites, including X‐ray photoelectron spectroscopy, surface area and surface acid‐base property detection. A one‐step method for isolation and identification of phosphopeptides from peptide mixture was created using these ceria‐zirconia composites. Using tryptic digest of standard phosphorylated protein, we have shown that these enrichment and dephosphorylation activities are effective. The adsorption capacity and catalytic property of ceria‐zirconia composites at different molar ratios and calcinated temperatures were studied. In combination with MALDI‐TOF‐based peptide mass finger printing technique, we have established a method to utilize the enrichment/dephosphorylation dual properties of these ceria‐zirconia composites for the analysis of phosphoprotein in nonfat milk successfully. 相似文献
We report on a novel luminescent phenomenon in Y2O2S doped with Nd3+. After irradiation by a 261 nm ultraviolet (UV) light into the Y2O2S host lattice, the Nd3+-doped Y2O2S phosphor emits intense blue luminescence in the visible light region. Moreover, this blue luminescence can also be obtained by exciting directly into the Nd3+ energy absorption itself. XRD, photoluminescence, and fluorescence decay curve are used to characterize the synthesized phosphor. The spectroscopic data indicate that all the visible emission peaks are originated from the electrical transitions of Nd3+, and the strong luminescence of the Nd3+ is considered to be due to an efficient energy transfer from the Y2O2S host lattice to the Nd3+ in Y2O2S:Nd3+. The optimum concentration for the luminescence Nd3+ is determined to be 1 mol% of Y3+ in Y2O2S host. The critical energy transfer distance has been calculated by the concentration quenching and the possible luminescent process of this blue luminescence-emitting phosphor is also investigated. 相似文献
Treatment of Pd(PPh3)4 with 2‐bromo‐3‐hydroxypyridine [C5H3N(OH)Br] and 3‐amino‐2‐bromopyridine [C5H3N(NH2)Br] in dichloromethane at ambient temperature cause the oxidative addition reaction to produce the palladium complex [Pd(PPh3)2{η1‐C5H3N(OH)}(Br)], 2 and [Pd(PPh3)2{η1‐C5H3N(NH2)}(Br)], 3 , by substituting two triphenylphosphine ligands, respectively. In dichloromethane solution of complexes 2 and 3 at ambient temperature for 3 days, it undergo displacement of the triphenylphosphine ligand to form the dipalladium complexes [Pd(PPh3)Br]2{μ,η2‐C5H3N(OH)}2, 4 and [Pd(PPh3)Br]2{μ,η2‐C5H3N(NH2)}2, 5 , in which the two 3‐hydroxypyridine and 3‐aminopyridine ligands coordinated through carbon to one metal center and bridging the other metal through nitrogen atom, respectively. Complexes 4 and 5 are characterized by X‐ray diffraction analyses. 相似文献
Four new norditerpenoids, designated as cespihypotins A (1), B (2), C (3) and D (4), were isolated from Cespitularia hypotentaculata Roxas (Xeniidae) that was collected in Taiwan. Compounds 1 and 2 are unprecedented structures having 13- and 14-membered lactone ring, respectively. Their structures were elucidated on the basis of extensive spectroscopic analysis. A plausible biogenetic pathway for compounds 1-4 was also proposed. 相似文献
Modelling the dynamics of evolutionary competing species on a physical grid is a challenging modelling problem. This paper presents a novel modelling approach for synthesizing evolutionary dynamics of competing species using a spatial game perspective. This modelling approach describes the movement of players (‘species’ in our context) across a lattice. The model is based on a payoff function which controls the move likelihood and direction of the players (‘predators’ and ‘preys’). Using simulated results, the paper provides a comparison between the spatial game model and an existing predator-prey dynamic model. Finally, a case study is performed to illustrate the application of this formalism and validate the model. 相似文献
Conjugation of tripeptide derivatives with olsalazine, a clinically used anti-inflammatory prodrug, yields small molecules that self-assemble in water to form supramolecular hydrogels that undergo a gel-to-sol phase transition upon reduction, resulting in the controlled release of 5-aminosalicylic acid as the anti-inflammatory agent. This methodology will ultimately lead to new biomaterials for site-specific drug delivery. 相似文献
A new kind of supercapacitor by using chemical reduced graphene (CRG) as electrode material and ionic liquid with addition of acetonitrile as electrolyte is assembled and investigated. CRG materials with high surface area are prepared by chemical reduction of graphene oxide. The capacitive properties of the supercapacitor composed of the CRG and ionic liquid electrolyte are studied by electrical impedance spectroscopy, cyclic voltammetry and galvanostatic charge–discharge. With the combined advantages of graphene and ionic liquid, the supercapacitor shows perfect performance. The supercapacitor possesses wide cell voltage and good stability. The specific capacitance, energy density, and specific power density of the present supercapacitor are 132 Fg−1, 143.7 Wh kg−1, and 2.8 kW kg−1, respectively. The results demonstrate the potential application of electrical energy storage devices with high performance based on this new kind of supercapacitor.