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171.
Simon A. Butler Gillian W. Harris David S. Moss Beatrice A. Gorinsky Margaret J. Adams Sheila Gover 《Journal of chemical crystallography》1994,24(1):1-3
We report the estimation of random errors in the refinement of the rigid body displacements of the -helices of the enzyme 6-phosphogluconate dehydrogenase. Least-squares refinement of the TLS parameters of the helices has been carried out using X-ray reflection data of 2.1 Å resolution, resulting in anR-factor of 19.5%. Standard deviations were estimated from the normal matrix. The results show that the translational mean-square displacements of nearly all the helices are significant at this resolution. However the libration parameters are only significant when the helices have at least four turns. Screw-rotation tensor values cannot be determined at this resolution. 相似文献
172.
173.
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
174.
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
175.
Summary AssumeE is a real topological vector space,F is a real Banach space,K is a discrete subgroup ofF andC is a symmetric, convex and compact subset ofF such thatK (6C) = {0}. If a functionh:E F is continuous at at least one point andh(x + y) – h(x) – h(y) K + C for allx, y E, then there exists a continuous linear functiona:E F such thath(x) – a(x) K + C for everyx E. 相似文献
176.
Carl Faith 《Proceedings of the American Mathematical Society》1996,124(2):341-344
An overlooked corollary to the main result of the stated paper (Proc. Amer. Math. Soc. 120 (1994), 989--993) is that any Goldie ring of Goldie dimension 1 has Artinian classical quotient ring , hence is a Kerr ring in the sense that the polynomial ring satisfies the on annihilators . More generally, we show that a Goldie ring has Artinian when every zero divisor of has essential annihilator (in this case is a local ring; see Theorem ). A corollary to the proof is Theorem 2: A commutative ring has Artinian iff is a Goldie ring in which each element of the Jacobson radical of has essential annihilator. Applying a theorem of Beck we show that any ring that has Noetherian local ring for each associated prime is a Kerr ring and has Kerr polynomial ring (Theorem 5).
177.
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
178.
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.
179.
180.