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991.
In this paper we introduce two sequences of operator functions and their dual functions:f_k(t)=((tlog t)~k-(t-1)~k)/(log~k 1t)(k=1,2,...),gk(t)=((t-1)~k-log~k t)/(log~k 1t)(k=1,2,...)and f_k~*=(t~klog~(k 1)t)/((tlog t)~k-(t-1)~k)(k=1,2,...),g_k~*(t)=(t~klog~(k 1)t)/((t-1)~k-log~k t)(k=1,2,...)definedon(0, ∞). We find that they are all operator monotone functions with respect to the strictly chaotic order and some ordinary orders among positive invertible operators.Indeed,we extend the results of the operator monotone function(tlog t -t 1)/(log~2t)which is widely used in the theory of heat transfer of the heat engineering and fluid mechanics[1]. 相似文献
992.
Hongyao Xu Benhong Yang Jiafeng Wang Shanyi Guang Cun Li 《Journal of polymer science. Part A, Polymer chemistry》2007,45(22):5308-5317
The soluble poly(methyl methacrylate‐co‐octavinyl‐polyhedral oligomeric silsesquioxane) (PMMA–POSS) hybrid nanocomposites with improved Tg and high thermal stability were synthesized by common free radical polymerization and characterized using FTIR, high‐resolution 1H NMR, 29Si NMR, GPC, DSC, and TGA. The POSS contents in the nanocomposites were determined based on FTIR spectrum, revealing that it can be effectively adjusted by varying the feed ratio of POSS in the hybrid composites. On the basis of the 1H NMR analysis, the number of the reacted vinyl groups on each POSS molecules was determined to be about 6–8. The DSC and TGA measurements indicated that the hybrid nanocomposites had higher Tg and better thermal properties than the pure PMMA homopolymer. The Tg increase mechanism was investigated using FTIR, displaying that the dipole–dipole interaction between PMMA and POSS also plays very important role to the Tg improvement besides the molecular motion hindrance from the hybrid structure. The thermal stability enhances with increase of POSS content, which is mainly attributed to the incorporation of nanoscale inorganic POSS uniformly dispersed at molecular level. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5308–5317, 2007 相似文献
993.
A low temperature and cost-effective process for antimicrobial finishing of cotton textiles has been developed by sol–gel
method. The antimicrobial treatment was performed by treating cotton textile with silica sols from water glass and then with
silver nitrate solution. The antimicrobial activity was determined by using E. coli as a model for Gram-negative bacteria. The results showed that the treated textile has an excellent antimicrobial effect
and laundering durability. SEM analysis showed coarse surface morphological change on the water glass treated cotton textile.
The residual concentration of silver ion on fabrics was informed by ICP-MS. XPS results indicated that two different states
of silver were present on the surface of the antimicrobial textile. 相似文献
994.
《Physica A》2006,369(2):867-876
Amida-kuji is a Japanese traditional lottery. Amida-kuji is a simple network lottery which consists of vertical lines and horizontal lines. Japanese use Amida-kuji to divide people into several groups, to pick up a lucky guy from many people for cleanup duty, and so on. In this paper, we briefly explain about Amida-kuji, and then we give a new insight about Amida-kuji that is the probability distribution function (PDF) for positions on the Amida-kuji network obeying Fokker–Planck equation in one-dimensional diffusion process. 相似文献
995.
《Physics letters. A》2006,359(6):627-629
Via He's semi-inverse method, a variational principle is established for coupled nonlinear Schrödinger equations arising in nonlinear directional coupler. This Letter shows the effectiveness and convenience of the semi-inverse method. 相似文献
996.
Plasma surface-treatment of silk and cotton fabrics were carried out in a hexafluoropropene (C3F6) atmosphere under different experimental conditions. Analysis of the treated fibers by X-ray photoelectron spectroscopy (XPS) indicated about 50 at% fluorine atoms were incorporated in the surface structure of two fibers and confirmed the presence of -CF, -CF2, -CF3 groups on the surface. After water-washing and alcohol-extraction, though partial loss of fluorine from the surface has been observed, contact angle and wet-out time measurements on the fibers still show much improved hydrophobic properties. The other properties of the treated fabrics, such as water vapor permeability and tensile strength were also evaluated. 相似文献
997.
解非线性互补问题的约束积分水平集算法 总被引:1,自引:1,他引:0
本文考虑有约束的非线性互补问题的全局最优化问题,在文[1][5]的基础上,利用数论中一致分布佳点集列,给出了以数论方法代替Monte-Caclo投点的实现算法,并证明了所给实现算法的全局收敛性.最后所给出的两个数值例子表明本算法对求非线性互补问题是有效的. 相似文献
998.
Tian Q Tang M Jiang F Liu Y Wu J Zou R Sun Y Chen Z Li R Hu J 《Chemical communications (Cambridge, England)》2011,47(28):8100-8102
A cooperative thermal decomposition route to large-scaled star-shaped α-MnS nanocrystals, which show novel magnetic properties, i.e., a high blocking temperature (275 K) and a large coercive field (1573 Oe), is reported. 相似文献
999.
1000.
以琥珀酰亚胺为原料,经溴代、吲哚加成、与水合肼反应、酰基化和烷基化等反应,设计合成了6a~6c和7a~7b共5个新型N-苯甲酰胺基取代的双吲哚马来酰亚胺类化合物,其结构经IR,1H NMR和HRMS等进行了表征,并研究了该类化合物的紫外、荧光性能和热性质.研究表明,N-苯甲酰胺基取代的双吲哚马来酰亚胺类化合物的紫外吸收光谱在360~400和450~500 nm显示两个主要吸收峰,将N原子甲基化和苄基化后,紫外吸收峰波长发生红移.以化合物紫外最大吸收波长为激发波长,目标化合物的荧光发射光谱在560~620 nm有最大发射峰,7a有最大的荧光量子产率,7a在不同溶剂中随溶剂极性的增大,量子产率没有明显的变化规律,讨论了化合物的结构对荧光性能的影响.热学性质研究表明,化合物7a和7b的玻璃化转变温度(Tg)分别为116和80℃,目标化合物的分解温度接近400℃. 相似文献