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101.
102.
1D and 2D five-pulse ESEEM experiments on a PO 3 2? center in γ-irradiated betaine phosphite are presented to study the protons bound to the radical in more detail. The ESEEM results are in accordance with previous ENDOR investigations. From the 2D fivepulse ESEEM experiments the1H ENDOR assignment in the ferroelectric ordered state of betaine phosphite could be completed. Additionally, the occurrence of ordered proton states in the disordered paraelectric high-temperature phase and of disordered proton states in the ordered ferroelectric low-temperature phase as well could be observed due to the enhanced resolution of the 2D method. 相似文献
103.
Barry Simon 《Communications in Mathematical Physics》1996,176(3):713-722
We construct one-dimensional potentialsV(x) so that if
onL
2(), thenH has purely singular spectrum; but for a dense setD, D implies that |,e
-itH
|C
|t|-1/2 ln(|t|) for t>2. This implies the spectral measures have Hausdorff dimension one and also, following an idea of Malozemov-Molchanov, provides counterexamples to the direct extension of the theorem of Simon-Spencer on one-dimensional infinity high barriers.This material is based upon work supported by the National Science Foundation under Grant No. DMS-9401491. The Government has certain rights in this material. 相似文献
104.
Akiba Y Beavis D Beery P Britt HC Budick B Chasman C Chen Z Chi CY Chu YY Cianciolo V Cole BA Costales JB Crawford HJ Cumming JB Debbe R Engelage J Fung SY Gonin M Gushue S Hamagaki H Hansen O Hayano RS Hayashi S Homma S Kaneko H Kang J Kaufman S Kehoe WL Kurita K Ledoux RJ Levine MJ Miake Y Morrison DP Morse RJ Moskowitz B Nagamiya S Namboodiri MN Nayak TK Olness J Parsons CG Remsberg LP Roehrich D Rothschild P Sakurai H Sangster TC Seto R Soltz R Stankus P Steadman SG Stephans GS Sung T 《Physical review letters》1996,76(12):2021-2024
105.
Following the progression towards weaker logics, a number of authors have considered the notion of a sheaf over a quantale or, equivalently, a quantale valued set. In this paper, we use ideas from enriched category theory to motivate the definition of a quantic sheaf. Given a localic subquantale of Q, a quantic sheaf over Q gives a sheaf in the usual sense. As an application, we derive a series of sheaf representations for commutative rings including the familiar Pierce representation. 相似文献
106.
Jan Saxl Saharon Shelah Simon Thomas 《Transactions of the American Mathematical Society》1996,348(11):4611-4641
We classify the sequences of finite simple nonabelian groups such that has uncountable cofinality.
107.
108.
109.
110.
Simon G. Bott Duddu Raja Gopal Annavajhula Durga Prasad Alan P. Marchand 《Journal of chemical crystallography》1993,23(12):1013-1017
The structure of a compound derived from a symmetrical cage diketone in which one of the ketone C=O groups has been converted into a ketal is reported. An investigation into reasons for the selective functionalization resulted in the isolation of acis, cisoid, cis linear triquinane derivative in which both ketones are converted to ketals that share a transannular oxygen atom. Crystal data:2, monoclinic,P21/c,a=7.6298(9),b=7.673(3),c=22.125(3)Å,=97.59(1)°,V=1283.9(5)Å3, andR=0.048 (1001 reflections);4, triclinic,P¯1,a=7.3864(9),b=9.6362(9),c=10.3889(9)Å,=75.749(6),=76.300(8), =83.100(8)°,V=694.8(4)Å3, andR=0.088 (1284 reflections). 相似文献