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排序方式: 共有108条查询结果,搜索用时 14 毫秒
1.
四元缔合物体系薄层树脂相分离与光度法联用测定痕量钴   总被引:2,自引:0,他引:2  
提出了在酸性条件下 (pH=5.0),利用阳离子交换树脂-丁二酮肟-碘-钴四元体系,通过薄层树脂相光度法测定钴的新方法。本法灵敏度高 (e454=1.7105L/molcm),比水相光度法提高14倍,精密度理想 (测定2.0礸/ml Co(II) 6次,RSD=1.3%),选择性好。实测药品VB12及天然水中钴,线性范围0.024~2.0礸/ml (定容50ml),检出限10.4ng/ml。  相似文献   
2.
In this paper we investigate spectral matrices, i.e., matrices with equal spectral and numerical radii. Various characterizations and properties of these matrices are given.  相似文献   
3.
Dual electrodynamics and corresponding Maxwell’s equations (in the presence of monopole only) are revisited from dual symmetry and accordingly the quaternionic reformulation of field equations and equation of motion is developed in simple, compact and consistent manner.  相似文献   
4.
This paper first studies the solution of a complex matrix equation X - AXB = C, obtains an explicit solution of the equation by means of characteristic polynomial, and then studies the quaternion matrix equation X - A X B = C, characterizes the existence of a solution to the matrix equation, and derives closed-form solutions of the matrix equation in explicit forms by means of real representations of quaternion matrices. This paper also gives an application to the complex matrix equation X - AXB =C.  相似文献   
5.
Xiaolei Wang  Zhilei Li  Qi Ge 《Optik》2011,122(20):1856-1859
In this paper, a new method for color-image encryption using Discrete Quaternion Fourier-Transforms (DQFT) combined with double random-phase encryption is reported, by which color images can be processed as single channel architecture, instead of as separated color components in three channels, so that the complexity of the encryption system can be effectively reduced without any reduction of its security. The principle of both encryption and decryption is detailed and the noise robustness of the system has been examined experimentally.  相似文献   
6.
陈福元 《数学研究》1997,30(3):241-248
指出四元数阵重行列式可用复阵行列式来表示,于是,复阵的伴随矩阵、求逆阵公式、秩的下界等,都可相应地推广到四元数阵.  相似文献   
7.
A series of admissible wavelets is fixed, which forms an orthonormal basis for the Hilbert space of all the quaternion-valued admissible wavelets. It turns out that their corresponding admissible wavelet transforms give an orthogonal decomposition of L 2(IG(2), ℍ).   相似文献   
8.
In this paper we introduce the continuous quaternion wavelet transform (CQWT). We express the admissibility condition in terms of the (right-sided) quaternion Fourier transform. We show that its fundamental properties, such as inner product, norm relation, and inversion formula, can be established whenever the quaternion wavelets satisfy a particular admissibility condition. We present several examples of the CQWT. As an application we derive a Heisenberg type uncertainty principle for these extended wavelets.  相似文献   
9.
In this paper, we derive an alternative more condensed Cramer rule for the unique solution of some restricted left and right systems of quaternion linear equations. The findings of this paper extend some known results in the literature.  相似文献   
10.
We prove that the restriction operator for the sublaplacian on the quaternion Heisenberg group is bounded from L p to L p if 1 ≤ p ≤ 4 3 . This is different from the Heisenberg group, on which the restriction operator is not bounded from L p to L p unless p = 1.  相似文献   
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