A new protoilludane sesquiterpenoid aromatic ester,named armillarizin (1)has been isolated from the artificially cultured mycelium of Armillaria me- llea(Vahl.ex Fr)Quel.(Tricholomataceae).Its structure was deduced on...A new protoilludane sesquiterpenoid aromatic ester,named armillarizin (1)has been isolated from the artificially cultured mycelium of Armillaria me- llea(Vahl.ex Fr)Quel.(Tricholomataceae).Its structure was deduced on the ba- sis of spectral analyses.The relative configuration was established from the nuclear Overhauser effects and from the values of ~1H-~1H coupling constants.展开更多
The localized molecular orbitals for typical bowl-shaped circulenes are obtained by the use of INDO-LMO method. It is found that these bowl-shaped circulenes with strained π-electron systems are still aromatic and th...The localized molecular orbitals for typical bowl-shaped circulenes are obtained by the use of INDO-LMO method. It is found that these bowl-shaped circulenes with strained π-electron systems are still aromatic and the rim π-bonds with larger localization form reactive regions for formation of buckminsterfullerene.展开更多
Silica has three major varieties of crystalline. Quartz is the main andabundant ingredient in the crust of our earth. While other varieties are formedby the heating of quartz. Silica quartz is a rich chemical structur...Silica has three major varieties of crystalline. Quartz is the main andabundant ingredient in the crust of our earth. While other varieties are formedby the heating of quartz. Silica quartz is a rich chemical structure containingenormous properties. Any chemical network or structure can be transformedinto a graph, where atoms become vertices and the bonds are converted toedges, between vertices. This makes a complex network easy to visualize towork on it. There are many concepts to work on chemical structures in termsof graph theory but the resolvability parameters of a graph are quite advanceand applicable topic. Resolvability parameters of a graph is a way to getting agraph into unique form, like each vertex or edge has a unique identification bymeans of some selected vertices, which depends on the distance of vertices andits pattern in a particular graph. We have dealt some resolvability parametersof SiO2 quartz. We computed the resolving set for quartz structure and itsvariants, wherein we proved that all the variants of resolvability parameters ofquartz structures are constant and do not depend on the order of the graph.展开更多
4-（4,6-Dimethoxyl-pyrimidin-2-yl）-3-thiourea carboxylic acid ethyl ester was synthesized by the reaction of 2-amino-4,6-dimethoxyl pyrimidine, potassium thiocyanate and methyl chloroformate in ethyl acetate. Single ...4-（4,6-Dimethoxyl-pyrimidin-2-yl）-3-thiourea carboxylic acid ethyl ester was synthesized by the reaction of 2-amino-4,6-dimethoxyl pyrimidine, potassium thiocyanate and methyl chloroformate in ethyl acetate. Single crystals suitable for X-ray measurement were obtained by recrystallization with the solvent of dimethyl formamide at room temperature. The crystal structure was determined by X-ray diffraction analysis. Crystallographic data： C10H14N4O4S, M, = 286.31, monoclinic, space group C2/c with a = 2.5309（3）, b = 0.67682（6）, c = 1.74237（19） nm, β = 114.744（3）°, V= 2.7106（5） nm3, Dc = 1.403 g/cm3, p = 0.225 mm-1, F（000） = 1200, Z= 8, R= 0.0514 and wR= 0.1529.展开更多
The development of ultra-high definition organic lightemitting diode (UHD-OLED) display technology has become a central research focus in both academic and industrial circles [1].To achieve this ambitious goal,signifi...The development of ultra-high definition organic lightemitting diode (UHD-OLED) display technology has become a central research focus in both academic and industrial circles [1].To achieve this ambitious goal,significant efforts have been made to develop narrowband organic emitters that meet rigorous spectral color purity standards.A major breakthrough occurred in 2016 when Hatakeyama’s team developed a novel class of organic emitters based on rigidπ-conjugated polycyclic aromatic hydrocarbon (PAH) structures,which integrate electron-rich nitrogen and electrondeficient boron centers [2].展开更多
文摘A new protoilludane sesquiterpenoid aromatic ester,named armillarizin (1)has been isolated from the artificially cultured mycelium of Armillaria me- llea(Vahl.ex Fr)Quel.(Tricholomataceae).Its structure was deduced on the ba- sis of spectral analyses.The relative configuration was established from the nuclear Overhauser effects and from the values of ~1H-~1H coupling constants.
文摘The localized molecular orbitals for typical bowl-shaped circulenes are obtained by the use of INDO-LMO method. It is found that these bowl-shaped circulenes with strained π-electron systems are still aromatic and the rim π-bonds with larger localization form reactive regions for formation of buckminsterfullerene.
基金This research is supported by the University program of Advanced Research(UPAR)and UAEU-AUA grants of United Arab Emirates University(UAEU)via Grant No.G00003271 and Grant No.G00003461.
文摘Silica has three major varieties of crystalline. Quartz is the main andabundant ingredient in the crust of our earth. While other varieties are formedby the heating of quartz. Silica quartz is a rich chemical structure containingenormous properties. Any chemical network or structure can be transformedinto a graph, where atoms become vertices and the bonds are converted toedges, between vertices. This makes a complex network easy to visualize towork on it. There are many concepts to work on chemical structures in termsof graph theory but the resolvability parameters of a graph are quite advanceand applicable topic. Resolvability parameters of a graph is a way to getting agraph into unique form, like each vertex or edge has a unique identification bymeans of some selected vertices, which depends on the distance of vertices andits pattern in a particular graph. We have dealt some resolvability parametersof SiO2 quartz. We computed the resolving set for quartz structure and itsvariants, wherein we proved that all the variants of resolvability parameters ofquartz structures are constant and do not depend on the order of the graph.
基金supported by the National Natural Science Foundation of China (20571060)Natural Science Foundation of Shaanxi Province (2007B08)Education Committee of Shaanxi Province (05JK294)
文摘4-（4,6-Dimethoxyl-pyrimidin-2-yl）-3-thiourea carboxylic acid ethyl ester was synthesized by the reaction of 2-amino-4,6-dimethoxyl pyrimidine, potassium thiocyanate and methyl chloroformate in ethyl acetate. Single crystals suitable for X-ray measurement were obtained by recrystallization with the solvent of dimethyl formamide at room temperature. The crystal structure was determined by X-ray diffraction analysis. Crystallographic data： C10H14N4O4S, M, = 286.31, monoclinic, space group C2/c with a = 2.5309（3）, b = 0.67682（6）, c = 1.74237（19） nm, β = 114.744（3）°, V= 2.7106（5） nm3, Dc = 1.403 g/cm3, p = 0.225 mm-1, F（000） = 1200, Z= 8, R= 0.0514 and wR= 0.1529.
基金supported by the National Natural Science Foundation of China (22275127,22471183)the Sichuan Science and Technology Program (2025ZNSFSC0116)+3 种基金the Natural Science Foundation of Sichuan,China (2024NSFSC0223)the Fundamental Research Funds for the Central Universitiesthe projects supported by the TCL Science and Technology Innovation Fundthe support of Testing Center of Sichuan University。
文摘The development of ultra-high definition organic lightemitting diode (UHD-OLED) display technology has become a central research focus in both academic and industrial circles [1].To achieve this ambitious goal,significant efforts have been made to develop narrowband organic emitters that meet rigorous spectral color purity standards.A major breakthrough occurred in 2016 when Hatakeyama’s team developed a novel class of organic emitters based on rigidπ-conjugated polycyclic aromatic hydrocarbon (PAH) structures,which integrate electron-rich nitrogen and electrondeficient boron centers [2].
