A new and efficient Pd(II)/AgNO₃-cocatalyzed homocoupling of aromatic terminal alkynes is described. Various symmetrical 1,4-disubstituted-1,3-diynes are obtained in good to excellent yields. This protocol employs a loading with relatively low palladium(II) in aqueous media under aerobic conditions.
Saussurea involucrata Kar. et Kir. tolerates severe abiotic stresses including cold, and the level of membrane fatty acid desaturation is associated with its cold acclimation. We discovered and characterized a full-length cDNA of stearoyl acyl-carrier-protein desaturase (sikSACPD) which encodes a protein consisted of 396 amino acids. A sequence alignment of… (More)
Regularization is a solution for the problem of unstable estimation of covariance matrix with a small sample set in Gaussian classifier. In many applications such as image restoration, sparse representation, we have to deal with multi-regularization parameters problem. In this paper, the case of covariance matrix estimation with multi-regularization… (More)
Regularization is a solution to solve the problem of unstable estimation of covariance matrix with a small sample set in Gaussian classifier. And multi-regularization parameters estimation is more difficult than single parameter estimation. In this paper, KLIM_L covariance matrix estimation is derived theoretically based on MDL (minimum description length)… (More)