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121.
122.
123.
We characterize the finite Veronesean
of all Hermitian varieties of PG(n,q2) as the unique representation of PG(n,q2) in PG(d,q), d n(n+2), where points and lines of PG(n,q2) are represented by points and ovoids of solids, respectively, of PG(d,q), with the only condition that the point set of PG(d,q) corresponding to the point set of PG(n,q2) generates PG(d,q). Using this result for n=2, we show that
is characterized by the following properties: (1)
; (2) each hyperplane of PG(8,q) meets
in q2+1, q3+1 or q3+q2+1 points; (3) each solid of PG(8,q) having at least q+3 points in common with
shares exactly q2+1 points with it.51E24 相似文献
124.
The modulus semigroup for linear delay equations III 总被引:1,自引:0,他引:1
In this paper, we describe the modulus semigroup of the C0-semigroup associated with the linear differential equation with delay in the Banach lattice X×Lp(-h,0;X), where X is a Banach lattice with order continuous norm. The progress with respect to previous papers is that A may be an unbounded generator of a C0-semigroup possessing a modulus semigroup. 相似文献
125.
A concise and convergent route to combretastatin D2 is described together with some preliminary biological data. 相似文献
126.
Ashfold MN Nahler NH Orr-Ewing AJ Vieuxmaire OP Toomes RL Kitsopoulos TN Garcia IA Chestakov DA Wu SM Parker DH 《Physical chemistry chemical physics : PCCP》2006,8(1):26-53
Ion imaging methods are making ever greater impact on studies of gas phase molecular reaction dynamics. This article traces the evolution of the technique, highlights some of the more important breakthroughs with regards to improving image resolution and in image processing and analysis methods, and then proceeds to illustrate some of the many applications to which the technique is now being applied--most notably in studies of molecular photodissociation and of bimolecular reaction dynamics. 相似文献
127.
A tripodal sulfur ligand for the selective ruthenium-catalysed hydrogenation of dimethyl oxalate 总被引:1,自引:0,他引:1
Boardman B Hanton MJ van Rensburg H Tooze RP 《Chemical communications (Cambridge, England)》2006,(21):2289-2291
The first example of a catalyst utilising a sulfur-based ligand [MeC(CH2SBu)3] for the selective hydrogenation of dimethyl oxalate to methyl glycolate is reported. 相似文献
128.
Sisourat N Sann H Kryzhevoi NV Kolorenč P Havermeier T Sturm F Jahnke T Kim HK Dörner R Cederbaum LS 《Physical review letters》2010,105(17):173401
The interatomic electronic decay after inner-valence ionization of a neon atom by a single photon in a neon-helium dimer is investigated. The excited neon atom relaxes via interatomic Coulombic decay and the excess energy is transferred to the helium atom and ionizes it. We show that the decay process is only possible if the dimer's bond stretches up to 6.2 ?, i.e., to more than twice the equilibrium interatomic distance of the neutral dimer. Thus, it is demonstrated that the electronic decay, taking place at such long distances, is driven by the nuclear motion. 相似文献
129.
We give an “elementary” proof of an inequality due to Maz’ya. As a prerequisite we prove an approximation property for the Hausdorff measure. We also comment on the relations between Maz’ya’s inequality, the isoperimetric inequality, and the Sobolev inequality. 相似文献
130.
Hendrik Vogt 《Archiv der Mathematik》2010,95(1):31-34
We present a result on relative weak* compactness in the dual of a Banach space X that allows a short proof of both the Eberlein–Šmulian theorem and Šmulian’s characterisation of weak compactness of closed
convex subsets of X. 相似文献