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71.
We prove that if m and \({\nu}\) are integers with \({0 \leq \nu \leq m}\) and x is a real number, then
- $$\sum_{k=0 \atop k+m \, \, odd}^{m-1} {m \choose k}{k+m \choose \nu} B_{k+m-\nu}(x) = \frac{1}{2} \sum_{j=0}^m (-1)^{j+m} {m \choose j}{j+m-1 \choose \nu} (j+m) x^{j+m-\nu-1},$$ where B n (x) denotes the Bernoulli polynomial of degree n. An application of (1) leads to new identities for Bernoulli numbers B n . Among others, we obtain
- $$\sum_{k=0 \atop k+m \, \, odd}^{m -1} {m \choose k}{k+m \choose \nu} {k+m-\nu \choose j}B_{k+m-\nu-j} =0 \quad{(0 \leq j \leq m-2-\nu)}. $$ This formula extends two results obtained by Kaneko and Chen-Sun, who proved (2) for the special cases j = 1, \({\nu=0}\) and j = 3, \({\nu=0}\) , respectively.
72.
Man Kam Kwong 《Linear algebra and its applications》1977,18(3):223-228
Let A and B be two n×n non-negative matrices. We write A ? B iff for all column vectors u in Cn. Here u1 is the conjugate transpose of u. In this paper are stated equivalent conditions under which Ak ? Bk for all natural numbers k. The result is then generalized to Hermitian operators in a Hilbert space. 相似文献
73.
Li Ma Qian Wang Dr. Wai‐Lun Man Dr. Hoi‐Ki Kwong Dr. Chi‐Chiu Ko Prof. Tai‐Chu Lau 《Angewandte Chemie (International ed. in English)》2015,54(17):5246-5249
The study of manganese complexes as water‐oxidation catalysts (WOCs) is of great interest because they can serve as models for the oxygen‐evolving complex of photosystem II. In most of the reported Mn‐based WOCs, manganese exists in the oxidation states III or IV, and the catalysts generally give low turnovers, especially with one‐electron oxidants such as CeIV. Now, a different class of Mn‐based catalysts, namely manganese(V)–nitrido complexes, were explored. The complex [MnV(N)(CN)4]2− turned out to be an active homogeneous WOC using (NH4)2[Ce(NO3)6] as the terminal oxidant, with a turnover number of higher than 180 and a maximum turnover frequency of 6 min−1. The study suggests that active WOCs may be constructed based on the MnV(N) platform. 相似文献
74.
C. Droullé J. C. Adjizian J. M. Corcy A. Poynard F. Hui Tse Kwong G. Potron 《Fresenius' Journal of Analytical Chemistry》1984,317(6):747-748
Conclusion In clinical states, we did not found any correlation between the techniques using these two viscometers which appear complementary; probably in erythrocyte dysfunction, they allow a better approach of the environment and the influence, in some cases, of plasmatic factors upon erythrocyte deformability. From this point of view, we actually consider that different techniques are necessary to establish in vitro a schedule of rheological behavior.
Analyse von rheologischen Parametern: verschiedene Techniken相似文献
75.
76.
77.
E. Eisenhandler W.R. Gibson C. Hojvat P.I.P. Kalmus L.C.Y.Lee Chi Kwong T.W. Pritchard E.C. Usher D.T. Williams M. Harrison W.H. Range M.A.R. Kemp A.D. Rush J.N. Woulds G.T.J. Arnison A. Astbury D.P. Jones A.S.L. Parsons 《Physics letters. [Part B]》1973,47(6):536-540
The differential cross-sections for p → π?π+ in the momentum range 0.8 to 2.4 GeV/c (centre-of-mass energy 2.02 to 2.57 GeV) are analysed in terms of the possible existence of s-channel resonances. The systematics of the dip structures and the s-dependence of dσ/dt are presented. 相似文献
78.
A Michael-type reaction of β,γ-unsaturated α-keto ester and α-nitro ketone was established. With a thiourea catalyst derived from cinchona alkaloid, the reactions afford products in 47-94% yields with 68-96% ee. 相似文献
79.
Sham KC Zheng G Li Y Yiu SM Kwong HL 《Dalton transactions (Cambridge, England : 2003)》2011,40(45):12060-12062
Self assembly of phenyl bridged bisbipyridines with manganese perchlorate gave structurally different metallo-macrocycles having cis-labile coordination sites which can catalyse olefin epoxidation with peracetic acid in good yield. 相似文献
80.
Design and fabrication of a 2×2 two-mode interference (TMI) coupler based on-chip polarization splitter is presented. By changing the angle between the access waveguides, one can tune the effective TMI length for the mode with less optical confinement (transverse magnetic, TM) to coincide with the target TMI length for a desired transmission of the mode with higher optical confinement (transverse electric, TE). The fabricated 0.94?μm long 2×2 TMI splits the input power into TM (bar) and TE (cross) outputs with splitting ratio over 15?dB over 50?nm bandwidth. Fabrication tolerance analysis shows that the device is tolerant to fabrication errors as large as 60?nm. 相似文献