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971.
Plasma doping is the candidate for semiconductor doping. Accurate simulation of the doping technology is needed for the advanced integrated circuit manufacturing. In this paper, the plasma doping process simulation is performed by using the localized molecular dynamics method. Models that involve the statistics of the implanted compositions, angles and energies are developed. The effect of the model on simulation results is studied. The simulation results about the doping concentration profile are supported by experimental data. 相似文献
972.
973.
On Clique-Transversals and Clique-Independent Sets 总被引:1,自引:0,他引:1
Guillermo Durán Min Chih Lin Jayme L. Szwarcfiter 《Annals of Operations Research》2002,116(1-4):71-77
A clique-transversal of a graph G is a subset of vertices intersecting all the cliques of G. A clique-independent set is a subset of pairwise disjoint cliques of G. Denote by
C
(G) and
C
(G) the cardinalities of the minimum clique-transversal and maximum clique-independent set of G, respectively. Say that G is clique-perfect when
C
(H)=
C
(H), for every induced subgraph H of G. In this paper, we prove that every graph not containing a 4-wheel nor a 3-fan as induced subgraphs and such that every odd cycle of length greater than 3 has a short chord is clique-perfect. The proof leads to polynomial time algorithms for finding the parameters
C
(G) and
C
(G), for graphs belonging to this class. In addition, we prove that to decide whether or not a given subset of vertices of a graph is a clique-transversal is Co-NP-Complete. The complexity of this problem has been mentioned as unknown in the literature. Finally, we describe a family of highly clique-imperfect graphs, that is, a family of graphs G whose difference
C
(G)–
C
(G) is arbitrarily large. 相似文献
974.
Young Min Han Slavisa V. Djordjevic 《Proceedings of the American Mathematical Society》2002,130(3):715-722
If is a upper triangular matrix on the Hilbert space , then -Weyl's theorem for and need not imply -Weyl's theorem for , even when . In this note we explore how -Weyl's theorem and -Browder's theorem survive for operator matrices on the Hilbert space.
975.
An inductively coupled plasma atomic emission spectrometry (ICP-AES) method was developed for the determination of phosphorus in fertilizers. Total phosphorus, direct extraction available phosphorus (EDTA), and water-soluble phosphorus, reported as phosphorus pentoxide (P205), in 15 Magruder check fertilizers were measured by ICP-AES, and the results were compared with those obtained by the AOAC official method. Five analytical wavelengths of phosphorus, 177.499, 178.287, 213.618, 214.914, and 253.565 nm, were tested for the determination of phosphorus in fertilizers, and their detection limits were obtained. Acid effects of perchloric acid and possible matrix effects of aluminum, calcium, magnesium, potassium, and sodium were negligible for phosphorus determination. Wavelength 213.618 nm was the best analytical wavelength for phosphorus determination by all 3 sample preparation methods for the selected Magruder fertilizers. The results demonstrated that the accuracy and precision of the ICP-AES method were comparable with those of the official methods. 相似文献
976.
We have developed a simple method to dramatically improve Western blotting by use of water washing as well as altered buffer conditions. Our improved protocol reduces the cost and labor of Western blotting by shortening the washing time and uses less buffer and other reagents. This procedure does not significantly change existing protocols of Western blotting analysis; it simply contains a few modifications to the washing step and buffer conditions. Our improved technique may therefore have broad applications in various experimental conditions. 相似文献
977.
Kuz'mina N. P. Eliseeva S. V. Chugarov N. V. Martynenko L. I. Yo-Sep Min Dae-Sig Kim 《Russian Journal of Coordination Chemistry》2002,28(9):603-607
Pivaloylacetonates of alkaline-earth elements with composition M(Pa)2 · nH2O (n = 1, M = Sr, Ca; n = 0, 2, M = Ba) were synthesized and studied by IR and thermal analysis; their solubilities and volatility were estimated. It was found that the volatility changes regularly in the series M(Acac)2–M(Pa)2–M(Thd)2 (HAcac is acetylacetone, HThd is dipivaloylmethane). The replacement of one methyl radical by the tert-butyl radical when going from acetylacetonates to pivaloylacetonates was shown to noticeably increase the volatility only for Sr(Pa)2 · H2O. Complexes of barium pivaloylacetonate with tetraglyme and -phenanthroline were synthesized and characterized. 相似文献
978.
In this paper, we describe a practical, useful electrophilic aromatic nitration process in fluorous phase by using perfluorodecalin (C10F18, cis- and trans-mixture) as a fluorous solvent and perfluorinated rare earth metal salt [Yb(OSO2C8F17)3] as a catalyst for the electrophilic aromatic nitration. 相似文献
979.
High chemical yields and good enantiomeric excesses are obtained by using soluble polymer-supported tartrate ester in the epoxidation of trans-hex-2-en-1-ol using Ti(OPri)4/tert-butyl hydroperoxide. 相似文献
980.