We report the structural characterization and proposed formation mechanism of honeycomb-like ZnO conglomerations fabricated by direct precipitation method. X-ray diffraction （XRD）, energy-disperse X-ray spectrometry...We report the structural characterization and proposed formation mechanism of honeycomb-like ZnO conglomerations fabricated by direct precipitation method. X-ray diffraction （XRD）, energy-disperse X-ray spectrometry （EDS）, scanning electron microscopy （SEM） showed that the as-prepared ZnO calcined at 700 ℃ were micron sphere particles with honeycomb-like structure. In the UV-vis absorbing spectrum, it was observed that there is a new additional absorption band at 260 nm, and it was speculated that the absorption may be caused by defects on the surface and interface of honeycomb-like ZnO. The as-products showed high sensitivity and short response time to sulfured hydrogen gas. These results demonstrate that honeycomb-like ZnO conglomerations are very promising materials for fabricating H2S gas sensors.展开更多
A series of novel N-[α-(isoflavone-7-O-)acetyl] amino acid methyl esters were prepared from the efficient and regioselective alkylation of isoflavones with chloroacetyl amino acid derivatives under mild condition.
The present paper reports the synthesis of two analogs of Schzandrin C (-DDB, (-DDB with the gallic acid as the starting material. The key step is the synthesis of monomer of (-DDB and (-DDB for coupling. (-DDB, (-DD...The present paper reports the synthesis of two analogs of Schzandrin C (-DDB, (-DDB with the gallic acid as the starting material. The key step is the synthesis of monomer of (-DDB and (-DDB for coupling. (-DDB, (-DDB have different yields in Ullmann coupling reaction under the same condition. The yield of (-DDB is little lower than that of (-DDB. The AM1 calculation demonstrates that ΔH of the Ullmann coupling reaction of (-DDB and (-DDB are different. The former is -175.76966KJ/mol and the later is -203.21246KJ/mol. This is in agreement with the fact that (-DDB has higher yield than (-DDB.展开更多
In present paper, the 2,3-diaryl-butadiene analogues were synthesized as anti-cancer agents. The structures were confirmed by (HNMR)-H-1 and elemental analysis.
Hepatitis B Virus (HBV) belongs to the family of hepadnaviridac which comprisesseveral animal viruses, including human HBV. woodchuck hepatitis (WHV). ground squirrelhepatitis virus (GSHV) and duck hepatitis B virus (...Hepatitis B Virus (HBV) belongs to the family of hepadnaviridac which comprisesseveral animal viruses, including human HBV. woodchuck hepatitis (WHV). ground squirrelhepatitis virus (GSHV) and duck hepatitis B virus (DHBV), These viruses share commonfeatures such as the genome organization, mode of replication and similar tropism tar hepatocytes'.2'-deoxyuridine-substituted biphenyl carboxylate was synthesized as anti-hepatitis B agents. Thestructure was confirmed by UV. IHNMR spectrum and elementary analysis.展开更多
基金the National Natural Science Foundation of China(No.20771095)He'nan Outstanding Youth Science Fund(No.0612002700)is gratefully acknowledged.
文摘We report the structural characterization and proposed formation mechanism of honeycomb-like ZnO conglomerations fabricated by direct precipitation method. X-ray diffraction （XRD）, energy-disperse X-ray spectrometry （EDS）, scanning electron microscopy （SEM） showed that the as-prepared ZnO calcined at 700 ℃ were micron sphere particles with honeycomb-like structure. In the UV-vis absorbing spectrum, it was observed that there is a new additional absorption band at 260 nm, and it was speculated that the absorption may be caused by defects on the surface and interface of honeycomb-like ZnO. The as-products showed high sensitivity and short response time to sulfured hydrogen gas. These results demonstrate that honeycomb-like ZnO conglomerations are very promising materials for fabricating H2S gas sensors.
文摘A series of novel N-[α-(isoflavone-7-O-)acetyl] amino acid methyl esters were prepared from the efficient and regioselective alkylation of isoflavones with chloroacetyl amino acid derivatives under mild condition.
基金the Henan Outstanding Younth and Natural Science Foundation of China
文摘The present paper reports the synthesis of two analogs of Schzandrin C (-DDB, (-DDB with the gallic acid as the starting material. The key step is the synthesis of monomer of (-DDB and (-DDB for coupling. (-DDB, (-DDB have different yields in Ullmann coupling reaction under the same condition. The yield of (-DDB is little lower than that of (-DDB. The AM1 calculation demonstrates that ΔH of the Ullmann coupling reaction of (-DDB and (-DDB are different. The former is -175.76966KJ/mol and the later is -203.21246KJ/mol. This is in agreement with the fact that (-DDB has higher yield than (-DDB.
文摘In present paper, the 2,3-diaryl-butadiene analogues were synthesized as anti-cancer agents. The structures were confirmed by (HNMR)-H-1 and elemental analysis.
文摘Hepatitis B Virus (HBV) belongs to the family of hepadnaviridac which comprisesseveral animal viruses, including human HBV. woodchuck hepatitis (WHV). ground squirrelhepatitis virus (GSHV) and duck hepatitis B virus (DHBV), These viruses share commonfeatures such as the genome organization, mode of replication and similar tropism tar hepatocytes'.2'-deoxyuridine-substituted biphenyl carboxylate was synthesized as anti-hepatitis B agents. Thestructure was confirmed by UV. IHNMR spectrum and elementary analysis.
