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131.
In the presence of N, N′‐dicyclohexylcarbodiimide (DCC), (Bu4N)2[Mo6O18(NAr)] ( 1 ) and (Bu4N)2[Mo6O17(NAr)2] ( 2 ), Ar = o‐CH3C6H4, have been synthesized via the reaction of [α‐Mo8O26]4— with o‐toluidine. If the hydrochloride salt of o‐toluidine was added into the reactive mixture, only the monofunctionalized imido derivative of [Mo6O19]2— was obtained; the bifunctionalized derivative of [Mo6O19]2— was exclusively synthesized in the presence of non‐protonated o‐toluidine. The molecular and crystal structures of the hybrid compounds 1 and 2 were determined by X‐ray single crystal diffraction, and their UV, IR and NMR spectra were compared. Additionally, a possible reaction mechanism was proposed. 相似文献
132.
The chemistry of organoimido derivatives of polyoxometalates (POMs) has received increasing interest. In recent decades, a great development of the synthetic chemistry of organoimido derivatives of POMs using different imido-releasing reagents has taken place, particularly the novel DCC-dehydrating protocol to prepare organoimido derivatives of POMs was developed recently by us and co-workers. Organoimido substituted POMs as valuable building blocks can construct novel nanostructured organic-inorganic hybrid molecular materials in well-developed common organic synthesis methods, such as Pd-catalyzed carbon-carbon coupling and esterification. Therefore, the reactive chemistry of organoimido derivatives of POMs stands for the fascinating future of the chemistry of organoimido derivatives of POMs. 相似文献
133.
Liu B Dong Q Wang M Shi L Wu Y Yu X Shi Y Shan Y Jiang C Zhang X Gu T Chen Y Kong W 《Chemical & pharmaceutical bulletin》2010,58(11):1474-1479
Exenatide (synthetic exendin-4), a 39-amino acid peptide, was encapsulated in poly(DL-lactic-co-glycolic acid) (PLGA) microspheres as a sustained release delivery system for the therapy of type 2 diabetes mellitus. The microspheres were prepared by a double-emulsion solvent evaporation method and the particle size, surface morphology, drug encapsulation efficiency, in vitro release profiles and in vivo hypoglycemic activity were evaluated. The results indicated that the morphology of the exenatide PLGA microspheres presented as a spherical shape with smooth surface, and the particle sizes distributed from 5.8 to 13.6 μm. The drug encapsulation efficiency tested by micro-bicinchoninic acid (BCA) assay was influenced by certain parameters such as inner and outer aqueous phase volume, PLGA concentration in oil phase, polyvinyl alcohol (PVA) concentrations in outer aqueous phase. Moreover, in vitro release behaviors were also affected by some parameters such as polymer type, PLGA molecular, internal aqueous phase volume, PLGA concentration. The pharmacodynamics in streptozotocin (STZ)-induced diabetic mice suggested that, exenatide microspheres have a significant hypoglycemic activity within one month, and its controlling of plasma glucose was similar to that of exenatide solution injected twice daily with identical exenatide amount. In conclusion, this microsphere could be a well sustained delivery system for exenatide to treat type 2 diabetes mellitus. 相似文献
134.
Yongge Tian 《Linear and Multilinear Algebra》2013,61(6):445-454
A set of rank equalities and inequalities are established for block matrices consisting of Kronecker products. Various consequences are also given. 相似文献
135.
Yongge Tian 《Linear and Multilinear Algebra》2013,61(2):111-125
The purpose of this article is to solve two problems related to solutions of a consistent complex matrix equation AXB = C : (I) the maximal and minimal ranks of solution to AXB = C , and (II) the maximal and minimal ranks of two real matrices X 0 and X 1 in solution X = X 0 + iX 1 to AXB = C . As applications, the maximal and minimal ranks of two real matrices C and D in generalized inverse (A + iB)- = C + iD of a complex matrix A + iB are also examined. 相似文献
136.
Yongge Tian 《Linear and Multilinear Algebra》2013,61(4):269-288
A matrix X is called an outer inverse for a matrix A if XAX=X. In this paper, we present some basic rank equalities for difference and sum of outer inverses of a matrix, and apply them to characterize various equalities related to outer inverses, Moore-Penrose inverses, group inverses, Drazin inverses and weighted Moore-Penrose inverses of matrices. 相似文献
137.
Yongge Tian 《Linear and Multilinear Algebra》2013,61(11):1237-1246
A square matrix A of order n is said to be tripotent if A 3?=?A. In this note, we give a nine-term disjoint idempotent decomposition for the linear combination of two commutative tripotent matrices and their products. Using the decomposition, we derive some closed-form formulae for the eigenvalues, determinant, rank, trace, power, inverse and group inverse of the linear combinations. In particular, we show that the linear combinations of two commutative tripotent elements and their products can produce 39?=?19,683 tripotent elements. 相似文献
138.
A complex square matrix A is called an orthogonal projector if A 2?=?A?=?A*, where A* is the conjugate transpose of A. In this article, we first give some formulas for calculating the distributions of real eigenvalues of a linear combination of two orthogonal projectors. Then, we establish various expansion formulas for calculating the inertias, ranks and signatures of some 2?×?2 and 3?×?3, as well as k?×?k block Hermitian matrices consisting of two orthogonal projectors. Many applications of the formulas are presented in characterizing interval distributions of numbers of eigenvalues, and nonsingularity of these block Hermitian matrices. In addition, necessary and sufficient conditions are given for various equalities and inequalities of these block Hermitian matrices to hold. 相似文献
139.
The crystal structure, band gap energy and bowing parameter of In-rich InxAl1−xN (0.7 < x < 1.0) films grown by magnetron sputtering were investigated. Band gap energies of InxAl1−xN films were obtained from absorption spectra. Band gap tailing due to compositional fluctuation in the films was observed. The band gap of the as-grown InN measured by optical absorption method is 1.34 eV, which is larger than the reported 0.7 eV for pure InN prepared by molecular beam epitaxy (MBE) method. This could be explained by the Burstein-Moss effect under carrier concentration of 1020 cm−3 of our sputtered films. The bowing parameter of 3.68 eV is obtained for our InxAl1−xN film which is consistent with the previous experimental reports and theoretical calculations. 相似文献
140.
Yongge Tian 《Mediterranean Journal of Mathematics》2012,9(1):47-60
The decomposition of a Hermitian solution of the linear matrix equation AXA* = B into the sum of Hermitian solutions of other two linear matrix equations A1X1A*1 = B1{A_{1}X_{1}A^{*}_{1} = B_{1}} and A2X2A*2 = B2{A_{2}X_{2}A^*_{2} = B_{2}} are approached. As applications, the additive decomposition of Hermitian generalized inverse C
− = A
− + B
− for three Hermitian matrices A, B and C is also considered. 相似文献