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251.
半序赋范空间及增算子的不动点定理 总被引:8,自引:1,他引:7
张宪 《应用泛函分析学报》2001,3(3):256-260
在赋范线性空间E中定义了由E上连续性泛函确定的半序,并由半序引出E上的锥,讨论了半序和锥的若干性质,最后证明了几个单调增算子的不动点定理。 相似文献
252.
设 A是增算子或减算子 .本文引入广义序 Lipschitz条件 ,不要求算子的任何紧性、连续性或凹凸性 ,由单调迭代技巧得到了方程 Ax=x的解的存在唯一性 .将所得结果应用于无界域上的 Hammerstein积分方程 ,得到了新结果 . 相似文献
253.
新型CuCl/Hβ沸石羰基化催化剂的制备与原位红外光谱表征 总被引:1,自引:0,他引:1
采用固态离子交换法在沸石中直接引进Cu(Ⅰ)活性中心,CuCl分子在Hβ沸石中与H^+交换和在沸石内表面单层分散两个过程同时发生,负载阈值为21.2%(CuCl%),调节CuCl和Hβ的配比,可得到从桥羟基被部分交换到所有羟基被完全交换的CuCl/Hβ从化剂。 相似文献
254.
陆美子 《应用数学和力学(英文版)》1983,4(3):377-384
This paper deals with the path-independent integrals in non-linear three-dimensional fracture dynamics.Both the nonli-near elastic case and the elastic-plastic case are considered,and some path-independent integrals have been worked out.Forexplaining the physical meaning of these integrals,a speci-men with plane notch is considered,and the relation betweenthe integral and dynamical crack extension force is establish-ed.Thus.such integrals may serve as a fracture criterionin nonlinear fracture dynamics. 相似文献
255.
The structures and the properties of small clusters are known to be quite different from those of the bulk material. Consequently, the focus of most studies is towards understanding the changes in electronic properties with increasing cluster size. Linear static electronic dipole polarizabilities of the BeN (N→∞) solid are obtained at the DFT(PWB91) level by extrapolation of ab initio calculations on BeN (N=1,…,132) clusters. For the mean polarizability, a [5s3p] basis set is shown to give accurate values if the tri‐periodic clusters are big enough. No calculation has yet been carried out on BeN (N→∞), but it is clear that these linear properties converge relatively slowly with cluster size. For BeN, cluster size up to N=90 atoms are sufficient to give limiting infinite solid polarizabilities with relatively small uncertainties. For N=132, the mean polarizability result is probably very accurate. These results suggest that DFT is a good method for the determination of these properties. © 2000 John Wiley & Sons, Inc. J Comput Chem 22: 230–240, 2001 相似文献
256.
Application of Almost Increasing Sequence for Absolute Riesz $|\overline{N}, p_n^{\alpha, \beta}; \delta|_k$ Summable Factor 下载免费PDF全文
Smita Sonker Rozy Jindal Lakshmi Narayan Mishra 《Journal of Nonlinear Modeling and Analysis》2021,3(3):377-384
In this paper, we generate an extended result by Bor and Seyhan concerning absolute Riesz summability factors. Further, we develop some well-known results from our main result. 相似文献
257.
The COVID −19 pandemic reminded us that we need better contingency plans to prevent the spread of infectious agents and the occurrence of epidemics or pandemics. Although the transmissibility of SARS-CoV-2 in water has not been confirmed, there are studies that have reported on the presence of infectious coronaviruses in water and wastewater samples. Since standard water treatments are not designed to eliminate viruses, it is of utmost importance to explore advanced treatment processes that can improve water treatment and help inactivate viruses when needed. This is the first study to investigate the effects of hydrodynamic cavitation on the inactivation of bacteriophage phi6, an enveloped virus used as a SARS-CoV-2 surrogate in many studies. In two series of experiments with increasing and constant sample temperature, virus reduction of up to 6.3 logs was achieved. Inactivation of phi6 at temperatures of 10 and 20 °C occurs predominantly by the mechanical effect of cavitation and results in a reduction of up to 4.5 logs. At 30 °C, the reduction increases to up to 6 logs, where the temperature-induced increased susceptibility of the viral lipid envelope makes the virus more prone to inactivation. Furthermore, the control experiments without cavitation showed that the increased temperature alone is not sufficient to cause inactivation, but that additional mechanical stress is still required. The RNA degradation results confirmed that virus inactivation was due to the disrupted lipid bilayer and not to RNA damage. Hydrodynamic cavitation, therefore, has the potential to inactivate current and potentially emerging enveloped pathogenic viruses in water at lower, environmentally relevant temperatures. 相似文献