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991.
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
992.
李启宁 《数学年刊A辑(中文版)》2021,42(4):441-458
本文的目的 是定义Hopf二重Ore扩张,讨论这种扩张的基本性质并研究Hopf代数的分次与Hopf二重Ore扩张之间的关系.作者还研究了连通分次Hopf代数的结构及其Hopf二重Ore扩张的同调性质. 相似文献
993.
一个环R称为有向有限的,如果对于x,y∈R,xy=1蕴涵着yx=1.本文我们首先建立有向有限环的某些新的刻画,然后考察了它们的某些性质. 相似文献
994.
应用著名的Dugundji延拓定理和Urysohn引理,将Hilbert空间E中有界闭凸集D上的k-集压缩映射和聚映射延拓到全空间,并给出了其在拓扑度计算方面的应用. 相似文献
995.
Many therapeutic proteins are small in size and are rapidly cleared from circulation. Consequently, half-life extension strategies have emerged to improve pharmacokinetic properties, including fusion or binding to long-lasting serum proteins, chemical modifications with hydrophilic polymers such as PEGylation, or, more recently, fusion to PEG mimetic polypeptides. In the present study, two different PEG mimetic approaches, the GlycoTAIL and the FlexiTAIL, were applied to increase the hydrodynamic radius of antibody fragments of different sizes and valencies, including scFv, diabody, and scFv-EHD2 fusion proteins. The GlycoTAIL and FlexiTAIL sequences of varying lengths are composed of aliphatic and hydrophilic residues, with the GlycoTAIL furthermore comprising N-glycosylation sites. All modified proteins could be produced in a mammalian expression system without reducing stability and antigen binding, and all modified proteins exhibited a prolonged half-life and increased drug disposition in mice. The strongest effects were observed for proteins comprising a FlexiTAIL of 248 residues. Thus, the GlycoTAIL and FlexiTAIL sequences represent a flexible and modular system to improve the pharmacokinetic properties of proteins. 相似文献
996.
997.
薛大为 《应用数学和力学(英文版)》1985,6(6):501-509
A method for establishing generalized variational principle is proposed in this paper. It is based on the analysis of mechanical meaning and it can be applied to problems in which the variational principles are needed but no corresponding variational principle is available. In this paper, the Hu-Washizu ’s generalized variational principle and the Hu’s generalized principle of complementary energy are derived from the mechanical meaning instead of from the generalization of the principle of minimum potenlial energy and the correct proofs of these two generaleed variational principles are given. It is also proved that this is wrong if one beleives that σij, eij and ui are independent variables each other based on the reason that these three kinds of variables are all contained in these two generalized variational principles. The condition of using these two variational principles in a correct manner is also explained. 相似文献
998.
Yu. G. Shondin 《Mathematical Notes》1999,66(6):764-776
In the paper we study supersymmetric models for point interaction perturbations of operators of Dirac type and their spectral
properties. Such models are considered in the class of odd self-adjoint operators in ℤ2-graded Pontryagin space. We present in detail the previously considered realization method of strongly singular perturbation
by means of their embedding into the theory of self-adjoint extensions. We describe odd self-adjoint extensions of odd symmetric
operators with deficiency indices (1,1) in ℤ2-graded Pontryagin space and squares of such extensions using Krein’s formula for the resolvent. The results obtained are
refined in application to singular perturbations of odd self-adjoint differential operators.
Translated fromMatematicheskie Zametki, Vol. 66, No. 6, pp. 924–940, December, 1999. 相似文献
999.
Li‐Tang Yan Jun Xu Zhen‐Yu Qian Bao‐Hua Guo Xu‐Ming Xie 《Macromolecular theory and simulations》2005,14(9):586-595
Summary: The kinetics of the chain extension reaction of a carboxyl‐terminated polymer using a bisoxazoline coupling agent was simulated by the Monte Carlo method based on the master equation. The effects of temperature and stepwise addition of the chain extender was examined. A comparison between simulated results and those calculated by an amended kinetic model was made. The results show that the highest coupling efficiency and the highest can be obtained when the initial concentrations of carboxyl and oxazoline groups are equal, which is in good agreement with the experiments. It is found that a higher reaction temperature could lead to a bigger coupling efficiency, a higher and narrower MWDs. The stepwise addition of the chain extender can only postpone the chain extension reaction, but cannot affect the final coupling efficiency and the MWDs when the concentration of the oxazoline group is lower than that of the carboxyl group. However, stepwise addition of the chain extender favors bigger coupling efficiency and narrower MWDs when the concentration of the oxazoline group exceeds that of the carboxyl group.
1000.
Thermally reversible polyesters were obtained by the ester formation reaction of thermoplastic polyesters with hydroxyl end groups and the diacid anhydride of tetra carboxylic acid as a thermally reversible chain extender. Typical example of the thermally reversible polyesters was obtained by the reaction of PBT (polyburylene terephthalate) and PMA (pyromellitic dianhydride). This material having twice as large molecular weight as the original PBT exhibited almost the same melt viscosity as the original. Also that thermally reversible chain extension reaction occurred without unfavorable side reaction such as cross-linking. This material shows both good processability and superior mechanical properties due to its thermally reversible characters. 相似文献