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991.
We consider an infinite extension K of a local field of zero characteristic which is a union of an increasing sequence of finite extensions. K is equipped with an inductive limit topology; its conjugate K; is a completion of K with respect to a topology given by certain explicitly written semi-norms. We construct and study a Gaussian measure, a Fourier transform, a fractional differentiation operator and a cadlag Markov process on K. If we deal with Galois extensions then all these objects are Galois-invariant. 相似文献
992.
993.
T. Datuashvili 《Georgian Mathematical Journal》1999,6(2):127-148
We investigate the question of the Kan extension in the case when all categories and functors are internal in the category of groups. Under certain assumptions we establish the necessary and sufficient conditions for the existence of internal Kan extensions. Questions related to this problem are also discussed. 相似文献
994.
Sh. Pkhakadze 《Georgian Mathematical Journal》1999,6(2):179-190
A system of contracting symbols is introduced for a N. Bourbaki type general mathematical theory corresponding to a general classical mathematical theory T. 相似文献
995.
Henrik Winkler 《Mathematische Nachrichten》2002,236(1):175-191
Let S be a densely defined and closed symmetric relation in a Hilbert space ℋ︁ with defect numbers (1,1), and let A be some of its canonical selfadjoint extensions. According to Krein's formula, to S and A corresponds a so‐called Q‐function from the Nevanlinna class N . In this note we show to which subclasses N γ of N the Q‐functions corresponding to S and its canonical selfadjoint extensions belong and specify the Q‐functions of the generalized Friedrichs and Krein‐von Neumann extensions. A result of L. de Branges implies that to each function Q ∈ N there corresponds a unique Hamiltonian H such that Q is the Titchmarsh‐Weyl coefficient of the two‐dimensional canonical system Jy′ = —zHy on [0, ∞) where Weyl's limit point case prevails at ∞. Then the boundary condition y(0) = 0 corresponds to a symmetric relation Tmin with defect numbers (1,1) in the Hilbert space L2H, and Q is equal to the Q‐function with respect to the extension corresponding to the boundary condition y1(0) = 0. If H satisfies some growth conditions at 0 or ∞, wepresent results on the corresponding Q‐functions and show under which conditions the generalized Friedrichs or Krein‐von Neumann extension exists. 相似文献
996.
Hao Yu HU 《数学学报(英文版)》2021,37(1):35-58
In this article, we investigate the shift of Abbes and Saito's ramification filtrations of the absolute Galois group of a complete discrete valuation field of positive characteristic under a purely inseparable extension. We also study a functoriality property for characteristic forms. 相似文献
997.
以异佛尔酮二异氰酸酯(IPD I)为扩链剂,以外消旋乳酸(D,L-LA)直接熔融聚合合成的低分子量聚外消旋乳酸(PDLLA)为预聚体,在四氢呋喃溶液中进行扩链得扩链产物Ⅰ。Ⅰ用粘均分子量(Mη),IR,1H NMR,DSC及X-射线衍射等表征。与2,4-甲苯二异氰酸酯(TD I)的扩链产物(Ⅱ)比较,Ⅰ成功地引入了NH和IPD I反应后的刚性片段,使M,ηTg,Tm,结晶度等相应提高。但由于IPD I反应活性不如TD I,故反应速率比用TD I时慢;Ⅰ分子中脂肪环的刚性不如苯环,TⅠg低于TⅡg。 相似文献
998.
Elif Kurnaz Ekmel Helvacioglu Nur Cicek Kekec Nihan Nugay Turgut Nugay Joseph P. Kennedy 《Journal of polymer science. Part A, Polymer chemistry》2019,57(11):1197-1208
We report the synthesis of high‐molecular‐weight linear polyisobutylenes (PIBs) and PIB networks from low‐molecular‐weight PIB by thiol‐ene click chemistry. Thus, liquid allyl‐telechelic PIB was reacted with small di‐ and tri‐thiols, and the thiolated intermediates chain‐extended by UV‐ or thermally induced free radical initiation to linear and crosslinked products. PIB networks were also prepared by crosslinking SH‐telechelic PIB with a small triallyl compound. Linear products were characterized by 1H NMR spectroscopy and GPC, and networks by FTIR spectroscopy, extractables, swelling, and permanent set. The effect of reaction conditions (nature of thiol chain extender, concentration of photo‐ and thermal initiators, UV radiation time, and reagent concentrations) on chain extension and crosslinking was investigated. Under well‐defined conditions high‐molecular‐weight PIBs and tight PIB networks were prepared. Thiol‐ene click chemistry provides novel thiolated PIB derivatives and is a useful strategy for the convenient preparation of high‐molecular‐weight rubbery PIBs and tight PIB networks from low‐molecular‐weight PIB precursors. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 相似文献
999.
1000.