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141.
142.
软X射线监测系统的建立与国际标准的比对 总被引:1,自引:0,他引:1
软X射线监测系统的建立,结构特点和性能,有效地解决了气体的吸收和窗膜的透过率等因素的影响。申请获得了美国布鲁克海文国家实验室(BNL)的用光时间,对监测系统的性能进行研究,并给出了该系统的精度及与国际标准的比对结果。 相似文献
143.
本文叙述了新铸铝光谱标样的制备过程,制备出的标样具有工艺先进,化学成分均匀,定值准确及校准曲线啮合系数高等特点。通过试用分析,结果与化学仲裁分析结果相符,很好地满足了光谱分析铸造铝合金化学成分对标样的需求。 相似文献
144.
145.
In this paper it is shown by using the Clifford algebra formalism that the usual Lorentz transformations of the three-dimensional (3D) vectors of the electric and magnetic fields E and B (which will be named as standard transformations (ST)) are different than the Lorentz transformations (LT) of well-defined quantities from the 4D spacetime. This difference between the ST and the LT is obtained regardless of the used algebraic objects (1-vectors or bivectors) for the representation of the electric and magnetic fields in the usual observer dependent decompositions of F. The LT correctly transform the whole 4D quantity, e.g., Ef : F · γ0, whereas the ST are the result of the application of the LT only to the part of Ef, i.e., to F, but leaving γ0 unchanged. The new decompositions of F in terms of 4D quantities that are defined without reference frames, i.e., the absolute quantities, are introduced and discussed. It is shown that the LT of the 4D quantities representing electric and magnetic fields correctly describe the motional electromotive force (emf) for all relatively moving inertial observers, whereas it is not the case with the ST of the 3D E and B. 相似文献
146.
C.?V.?A.?V.?B.?Chandra?RajuEmail author Prudhvi?R.?Chintalapati 《International Journal of Theoretical Physics》2005,44(4):443-455
Fritzsch type of mass matrices for the 2×2 case and appropriate Lagrangians enable the choice of Yukawa constants of the Lagrangians in terms of the gauge constants. The mass matrices for the four quarks are shown to be proportional to VL. The Cabibbo angle is computed to be 13∘36′. 相似文献
147.
Ahmed Laghribi 《Rendiconti del Circolo Matematico di Palermo》2004,53(3):325-336
In this note we completely study the standard splitting of quasi-Pfister forms and their neighbors, and we include some general
results on standard splitting towers of totally singular quadratic forms.
The author was supported by the European research network HPRN-CT-2002-00287 “AlgebraicK-Theory, Linear Algebraic Groups and Related Structures”. 相似文献
148.
A. Świtaj-Zawadka P. Konieczka J. Szczygelska-Tao J. F. Biernat J. Wójcik A. Przyjazny J. Namieśnik 《Chromatographia》2004,60(7-8):433-439
The paper presents the results of research on a novel type of matrix-free reference materials for volatile organic compounds based upon thermal decomposition of appropriate immobilized compounds. The effect of parameters such as the kind of support (silica gel, porous glass, glass fiber) and the method of chemical modification of the support surface on the amount of chloromethane released as the analyte has been investigated. It was demonstrated that the amount of chloromethane released during thermal decomposition of immobilized compounds formed on the surface of silica gel and porous glass was larger when trimethylamine rather than N-morpholine was used for the preparation of immobilized compound. Reproducibility of the chemical modification procedure using silica gel and the stability of support with the immobilized compound were also examined. The full uncertainty budget of determination of liberated amount of chloromethane has been calculated. 相似文献
149.
Alexander Postnikov Boris Shapiro 《Transactions of the American Mathematical Society》2004,356(8):3109-3142
For a graph , we construct two algebras whose dimensions are both equal to the number of spanning trees of . One of these algebras is the quotient of the polynomial ring modulo certain monomial ideal, while the other is the quotient of the polynomial ring modulo certain powers of linear forms. We describe the set of monomials that forms a linear basis in each of these two algebras. The basis elements correspond to -parking functions that naturally came up in the abelian sandpile model. These ideals are instances of the general class of monotone monomial ideals and their deformations. We show that the Hilbert series of a monotone monomial ideal is always bounded by the Hilbert series of its deformation. Then we define an even more general class of monomial ideals associated with posets and construct free resolutions for these ideals. In some cases these resolutions coincide with Scarf resolutions. We prove several formulas for Hilbert series of monotone monomial ideals and investigate when they are equal to Hilbert series of deformations. In the appendix we discuss the abelian sandpile model.
150.
Tomislav Ivezić 《Foundations of Physics》2003,33(9):1339-1347
In this paper it is exactly proved that the standard transformations of the three-dimensional (3D) vectors of the electric and magnetic fields E and B are not relativistically correct transformations. Thence the 3D vectors E and B are not well-defined quantities in the 4D space-time and, contrary to the general belief, the usual Maxwell equations with the 3D E and B are not in agreement with the special relativity. The 4-vectors E
a
and B
a
, as well-defined 4D quantities, are introduced instead of ill-defined 3D E and B. The proof is given in the tensor and the Clifford algebra formalisms. 相似文献