We investigate synchronization in an array network of nearest-neighbor coupled chaotic oscillators. By using of the Lyapunov stability theory and matrix theory, a criterion for stability of complete synchronization is...We investigate synchronization in an array network of nearest-neighbor coupled chaotic oscillators. By using of the Lyapunov stability theory and matrix theory, a criterion for stability of complete synchronization is deduced. Meanwhile, an estimate of the critical coupling strength is obtained to ensure achieving chaos synchronization. As an example application, a model of coupled Chua's circuits with linearly bidirectional coupling is studied to verify the validity of the criterion.展开更多
The article analysis the external market environment and the situation of requirement and the competitor in market of office building with the same rank and the same type according to market research, the aim is to re...The article analysis the external market environment and the situation of requirement and the competitor in market of office building with the same rank and the same type according to market research, the aim is to research the whole processing operation and management, including making the marker orientation, confirming and finding the potential lesse making the rent plan, negotiating and signing the contract.展开更多
The isotopomers of halogenated amino acids (2'-F-L-phenylalanine, 3'-F- and 3'-Cl-L-tyrosine, as well as 5'-F-, 5'-Br-and 6'-F-L-tryptophan) specifically labeled with deuterium at α- and 13-carbon atom of the...The isotopomers of halogenated amino acids (2'-F-L-phenylalanine, 3'-F- and 3'-Cl-L-tyrosine, as well as 5'-F-, 5'-Br-and 6'-F-L-tryptophan) specifically labeled with deuterium at α- and 13-carbon atom of the side chain were synthesized by enzymatic catalyzed H/D exchange in fully deuteriated incubation medium. The extent and site of deuterium incorporation were confirmed by ^1H NMR (proton nuclear magnetic resonance) spectra.展开更多
Let An(R) be the set of symmetric matrices over Z/p^kZ with order n, where n 〉 2, p is a prime, p 〉 2 and p≡1(mod4), k 〉 1. By determining the normal form of n by n symmetric matrices over Z/p^kZ, we compute t...Let An(R) be the set of symmetric matrices over Z/p^kZ with order n, where n 〉 2, p is a prime, p 〉 2 and p≡1(mod4), k 〉 1. By determining the normal form of n by n symmetric matrices over Z/p^kZ, we compute the number of the orbits of An(R) and then compute the order of the orthogonal group determined by the special symmetric matrix. Finally we get the number of the symmetric matrices which are in the same orbit with the special symmetric matrix.展开更多
p-Quinols are ubiquitous structural motifs of various natural products and pharmaceutical compounds,and versatile building blocks in synthetic chemistry.The reported methods for the synthesis of p-quinol require stoic...p-Quinols are ubiquitous structural motifs of various natural products and pharmaceutical compounds,and versatile building blocks in synthetic chemistry.The reported methods for the synthesis of p-quinol require stoichiometric amounts of oxidants.Molecular oxygen is considered as an ideal oxidant due to its natural,inexpensive,and environmentally friendly characteristics.During the ongoing research of C–H bond hydroxylation,we found that multi-alkyl phenols could react with molecular oxygen under mild conditions.Herein,we describe an efficient oxidative de-aromatization of multi-alkyl phenols to p-quinols.1 atm of molecular oxygen was used as the oxidant.Many multi-alkyl phenols could react smoothly at room temperature.Isotopic labeling experiment was also performed,and the result proved that the oxygen atom in the produced hydroxyl group is from molecular oxygen.展开更多
基金supported by National Natural Science Foundation under Grant Nos.10872014 and 10702023
文摘We investigate synchronization in an array network of nearest-neighbor coupled chaotic oscillators. By using of the Lyapunov stability theory and matrix theory, a criterion for stability of complete synchronization is deduced. Meanwhile, an estimate of the critical coupling strength is obtained to ensure achieving chaos synchronization. As an example application, a model of coupled Chua's circuits with linearly bidirectional coupling is studied to verify the validity of the criterion.
文摘The article analysis the external market environment and the situation of requirement and the competitor in market of office building with the same rank and the same type according to market research, the aim is to research the whole processing operation and management, including making the marker orientation, confirming and finding the potential lesse making the rent plan, negotiating and signing the contract.
文摘The isotopomers of halogenated amino acids (2'-F-L-phenylalanine, 3'-F- and 3'-Cl-L-tyrosine, as well as 5'-F-, 5'-Br-and 6'-F-L-tryptophan) specifically labeled with deuterium at α- and 13-carbon atom of the side chain were synthesized by enzymatic catalyzed H/D exchange in fully deuteriated incubation medium. The extent and site of deuterium incorporation were confirmed by ^1H NMR (proton nuclear magnetic resonance) spectra.
基金the Key Project of Chinese Ministry of Education (03060)
文摘Let An(R) be the set of symmetric matrices over Z/p^kZ with order n, where n 〉 2, p is a prime, p 〉 2 and p≡1(mod4), k 〉 1. By determining the normal form of n by n symmetric matrices over Z/p^kZ, we compute the number of the orbits of An(R) and then compute the order of the orthogonal group determined by the special symmetric matrix. Finally we get the number of the symmetric matrices which are in the same orbit with the special symmetric matrix.
基金supported by the National Natural Science Foundation of China(21325206,21172006)the Key Laboratory of Oil and Gas Fine Chemicals(XJDX0908-2013-2)
文摘p-Quinols are ubiquitous structural motifs of various natural products and pharmaceutical compounds,and versatile building blocks in synthetic chemistry.The reported methods for the synthesis of p-quinol require stoichiometric amounts of oxidants.Molecular oxygen is considered as an ideal oxidant due to its natural,inexpensive,and environmentally friendly characteristics.During the ongoing research of C–H bond hydroxylation,we found that multi-alkyl phenols could react with molecular oxygen under mild conditions.Herein,we describe an efficient oxidative de-aromatization of multi-alkyl phenols to p-quinols.1 atm of molecular oxygen was used as the oxidant.Many multi-alkyl phenols could react smoothly at room temperature.Isotopic labeling experiment was also performed,and the result proved that the oxygen atom in the produced hydroxyl group is from molecular oxygen.