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91.
With less than 0# two generic extensions ofL are identified: one in which ${\aleph_1}With less than 0# two generic extensions ofL are identified: one in which à1{\aleph_1}, and the other à2{\aleph_2}, is almost precipitous. This improves the consistency strength upper bound of almost precipitousness obtained in Gitik M,
Magidor M (On partialy wellfounded generic ultrapowers, in Pillars of Computer Science, 2010), and answers some questions
raised there. Also, main results of Gitik (On normal precipitous ideals, 2010), are generalized—assumptions on precipitousness
are replaced by those on ∞-semi precipitousness. As an application it is shown that if δ is a Woodin cardinal and there is an f:w1 ? w1{f:\omega_1 \to \omega_1} with ||f||=w2{\|f\|=\omega_2}, then after Col(à2,d){Col(\aleph_2,\delta)} there is a normal precipitous ideal over à1{\aleph_1}. The existence of a pseudo-precipitous ideal over a successor cardinal is shown to give an inner model with a strong cardinal. 相似文献
92.
93.
Yuri V. Sushko Bruno DeHarak Gang Cao G. Shaw D.K. Powell J.W. Brill 《Solid State Communications》2004,130(5):341-346
Hydrostatic pressure effects on the temperature- and magnetic field dependencies of the in-plane and out-of-plane magnetization of the bi-layered perovskite Sr3Ru2O7 have been studied by SQUID magnetometer measurements under a hydrostatic helium-gas pressure. The anomalously enhanced low-temperature value of the paramagnetic susceptibility has been found to systematically decrease with increasing pressure. The effect is accompanied by an increase of the temperature Tmax of a pronounced peak of susceptibility. Thus, magnetization measurements under hydrostatic pressure reveal that the lattice contraction in the structure of Sr3Ru2O7 promotes antiferromagnetism and not ferromagnetism. The effects can be explained by the enhancement of the inter-bi-layer antiferromagnetic spin coupling, driven by the shortening of the superexchange path, and suppression, due to the band-broadening effect, of competing itinerant ferromagnetic correlations. 相似文献
94.
Brent?CodyEmail author Moti?Gitik Joel?David?Hamkins Jason?A.?Schanker 《Archive for Mathematical Logic》2015,54(5-6):491-510
We prove from suitable large cardinal hypotheses that the least weakly compact cardinal can be unfoldable, weakly measurable and even nearly \({\theta}\)-supercompact, for any desired \({\theta}\). In addition, we prove several global results showing how the entire class of weakly compactcardinals, a proper class, can be made to coincide with the class of unfoldable cardinals, with the class of weakly measurable cardinals or with the class of nearly \({\theta_\kappa}\)-supercompact cardinals \({\kappa}\), for nearly any desired function \({\kappa\mapsto\theta_\kappa}\). These results answer several questions that had been open in the literature and extend to these large cardinals the identity-crises phenomenon, first identified by Magidor with the strongly compact cardinals. 相似文献
95.
Danny Q. Thach Zachary G. Brill Huck K. Grover Kenneth V. Esguerra Jordan K. Thompson Thomas J. Maimone 《Angewandte Chemie (International ed. in English)》2020,59(4):1532-1536
The ophiobolin sesterterpenes are notable plant pathogens which have recently elicited significant chemical and biological attention because of their intriguing carbogenic frameworks, reactive functionalities, and emerging anticancer profiles. Reported herein is a total synthesis of (+)‐6‐epi‐ophiobolin A in 14 steps, a task which addresses construction of the synthetically challenging spirocyclic tetrahydrofuran motif as well as several other key stereochemical problems. This work demonstrates a streamlined synthetic platform to complex ophiobolins leveraging disparate termination modes of a radical polycyclization cascade for divergent elaboration and functionalization. 相似文献
96.
We prove that the Axiom of Full Reflection at a measurable cardinal is equiconsistent with the existence of a measurable cardinal.
We generalize the result also to larger cardinals such as strong or supercompact cardinals. 相似文献
97.
Moti Gitik 《Israel Journal of Mathematics》1997,99(1):175-188
This paper is a continuation of [Gi]. We show that the upper bound of [Gi] on the strength of NS
μ
+ precipitous for a regular μ is exact. The upper bounds on the strength of NSκ precipitous for inaccessible κ are reduced quite close to the lower bounds. 相似文献
98.
We consider a question of T. Jech and K. Prikry that asks if the existence of a precipitous filter implies the existence of a normal precipitous filter. The aim of this paper is to improve a result of Gitik (Israel J Math, 175:191?C219, 2010) and to show that measurable cardinals of a higher order rather than just measurable cardinals are necessary in order to have a model with a precipitous filter but without a normal one. 相似文献
99.
Aditya Sharma K. D. Verma Mayora Varshney Devendra Singh Moti Singh K. Asokan 《辐射效应与固体损伤》2013,168(12):930-937
In this paper, we present the impact of swift heavy ion beam irradiation on the structural, optical and electronic properties of SnO2 thin films. Thin films were deposited using the pulsed laser deposition technique on Al2O3 substrates. Atomic force microscopy, X-ray diffraction, UV–visible absorption and temperature-dependent resistivity measurements were performed to explore the morphological, structural, optical and electronic properties of the as-deposited and irradiated samples. The peak intensity of the (200) peak was found to decrease monotonously with increasing irradiation fluence. The band gap energy of the 1×1011 ion/cm2 irradiated sample was found to increase. The electrical resistivity of the samples showed a continuous increase with the irradiation fluence. 相似文献
100.
J. W. Brill 《Molecular Crystals and Liquid Crystals》2013,570(1):107-116
Abstract The temperature dependence of the Young's modulus and internal friction of TaS3 (orthorhombic) and NbSe3 have been measured by the vibrating reed technique. There is a large minimum 2%, in the modulus of TaS3 at the commensurate Peierls distortion (Tc = 222K) and the internal friction increases below Tc(ΔQ?1 = 5×10?5), although no critical relaxation effects are observed. On the other hand, a very small minimum, ΔE/E ~ 0.06%, is observed at the upper incommensurate transition in NbSe3, and a small broad increase (0.03%) at the lower transition. The measurements allow estimates to be made of the stress dependence of the transition temperature and of the electron-phonon coupling constant. 相似文献