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121.
In this article, under the hypotheses that E is a reflexive Banach space which has a weakly continuous duality mapping J ? with gauge function ?, we investigate several alternative viscosity approximation methods for finding some common fixed points of infinite non-expansive mappings, and prove two strong convergence theorems.  相似文献   
122.
In this paper, we prove existence and controllability results for first- and second-order semilinear differential inclusions in Banach spaces with nonlocal conditions.  相似文献   
123.
124.
A facile route to prepare lithium niobate (LiNbO3) powders was proposed by an alternative solid‐state method. Stoichiometric Li2C2O4 and ammonium niobium oxalate were mixed with small amounts of water and then dried at room temperature. It was demonstrated that Li[NbO(C2O4)2n H2O intermediate was produced by an ion‐exchange reaction. Pure LiNbO3 powders were successfully synthesized by heating the intermediate at 500, 600 and 700 °C for 3 h. X‐ray diffraction (XRD), scanning electron microscopy (SEM), Fourier‐transform infrared (FTIR) spectroscopy, UV‐Vis diffuse reflectance (UV‐Vis) spectroscopy and thermogravimetric (TG) analysis were used to characterize the precursor compound and as‐prepared samples. XRD results reveal that all the products are identified as hexagonal structure with high relative crystallinity (>87%). The particle size is found to be about 40 nm for the mixture calcined at 500 °C according to XRD data, which is in good agreement with SEM data. The as‐prepared LiNbO3 powders by this method are high quality according to FTIR spectra. (Li0.996Nb0.005)Nb0.999O3 phase was formed when the calcination temperature was raised to 800 °C. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
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126.
A generalized triangle group is a group that can be presented in the form where p,q,r ≥ 2 and w(x,y) is a cyclically reduced word of length at least 2 in the free product . Rosenberger has conjectured that every generalized triangle group G satisfies the Tits alternative. It is known that the conjecture holds except possibly when the triple (p,q,r) is one of (3, 3, 2), (3, 4, 2), (3, 5, 2), or (2, m, 2) where m=3, 4, 5, 6, 10, 12, 15 , 20, 30, 60. In this paper, we show that the Tits alternative holds in the cases (p,q,r)=(2, m, 2) where m=6, 10, 12, 15, 20, 30, 60.  相似文献   
127.
128.
In this paper, by measure theory, we introduce and investigate the concepts of (Stepanov-like) $(\mu,\nu)$-pseudo almost automorphic of class $r$ and class infinity, respectively. As applications, we establish some sufficient criteria for the existence, uniqueness of pseudo almost automorphic mild solutions to two-term fractional functional differential equations with finite or infinite delay. The working tools are based on the generalization of semigroup theory, Banach contraction mapping principle and Leray-Schauder alternative theorem. Finally, we explore the same topic for a fractional partial functional differential equation with delay.  相似文献   
129.
HCFC-22的替代物THR03的研究   总被引:11,自引:0,他引:11  
1前言HCFC-22作为空调与热泵机组的制冷剂而广泛存在。按照《蒙特利尔议定书》规定,发达国家将于2020年全面禁用含氢氯氟烃(HCFC)类物质,发展中国家也将于2030年禁用。现有的HCFC-22替代物中,呼声较高的有美国联合信号公司的R410A和R410B,杜邦公司与英国ICI公司的R407C,日本大金公司的R32/R134a。这些替代物各有优缺点,共同的缺陷在于若不采用改型措施,它们的制冷量和性能系数均比HCFC-22低,只有改型后,才有可能达到相同效果甚至更好。国内也已开始HCFC-22的替代研究工作,如西安交大和天津大学等。我们在长期…  相似文献   
130.
Summary A Hoeffding-type power comparison is made between the likelihood ratio and chi-square tests for a simple hypothesis in a multinomial. The power comparison is based on the fact that under an alternative hypothesis the distribution of the test statistic can be approximated by a normal distribution. The theory of large deviations is used to match the significance levels. This research was partially supported by the National Science Foundation Grant No. GP-33697X2, U.S. Energy Research and Development Agency Grant 7064100, Environmental Protection Agency Grant R805379-01-0 and U.S. Public Health Service Grant USPHS ES01299-15, at the University of California-Berkeley.  相似文献   
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