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131.
Let M
n
denote the partial maximum of a strictly stationary sequence (X
n
). Suppose that some of the random variables of (X
n
) can be observed and let [(M)\tilde]n\tilde M_n
stand for the maximum of observed random variables from the set {X
1, ..., X
n
}. In this paper, the almost sure limit theorems related to random vector ([(M)\tilde]n\tilde M_n
, M
n
) are considered in terms of i.i.d. case. The related results are also extended to weakly dependent stationary Gaussian sequence as its covariance function satisfies
some regular conditions. 相似文献
132.
Michael Addition Catalyzed by Chiral Secondary Amine Phosphoramide Using Fluorinated Silyl Enol Ethers: Formation of Quaternary Carbon Stereocenters 下载免费PDF全文
Jin‐Sheng Yu Fu‐Min Liao Wei‐Ming Gao Kui Liao Run‐Lin Zuo Prof. Dr. Jian Zhou 《Angewandte Chemie (International ed. in English)》2015,54(25):7381-7385
A chiral secondary amine phosphoramide was developed and identified as a powerful catalyst for the Mukaiyama–Michael addition of fluorinated enol silyl ethers to tetrasubstituted olefins. The resulting products are obtained with high enantioselectivities and contain a quaternary carbon stereocenter bearing either a difluoroalkyl or monofluoroalkyl group. 相似文献
133.
Bangmin Zhang Huaping Zuo Yuhua Xiao Guowei Wang Li Zhang 《Applied Surface Science》2010,256(21):6168-6171
A series of (Fe57Co24Ni4Nb2B13)x-(SiO2)1−x nano-granular thin films were fabricated by magnetron sputtering with different oblique incidence angle θ and excellent soft magnetic properties are achieved. Based on the results of magnetic field anneal at different temperature Ta, it is evidenced that orientation of atomic pairs contributes to the annealing treatment, and could manipulate magnetic anisotropy. The damping coefficient α decreases with increasing angle θ and this is ascribed to the anisotropy dissipation. 相似文献
134.
In this paper, a deteriorating simple repairable system with k + 1 states, including k failure states and one working state, is studied. The system after repair is not ‘as good as new’ and the deterioration of the system is stochastic. Under these assumptions, we study a replacement policy, called policy N, based on the failure number of the system. The objective is to maximize the long-run expected profit per unit time. The explicit expression of the long-run expected profit per unit time is derived and the corresponding optimal solution may be determined analytically or numerically. Furthermore, we prove that the model for the multistate system in this paper forms a general monotone process model which includes the geometric process repair model as a special case. A numerical example is given to illustrate the theoretical results. 相似文献
135.
136.
137.
138.
A simple and reliable RP-HPLC method has been developed for the simultaneous determination of ropivacaine and antipyrine in perfusate samples. Samples were analyzed on an ODS column with UV detection at 210 nm after liquid-liquid extraction. The mobile phase consisted of potassium dihydrogenphosphate (25 mM, adjusted to pH 5.0 with phosphoric acid)-acetonitrile (79:21, v/v). The method has been validated to be precise, accurate and linear. It has been applied to the investigation of placental transfer of ropivacaine via a dually perfused cotyledon model of human placenta in vitro. 相似文献
139.
利用液芯光纤技术研究了不同浓度的β-Carotene的CS2溶液的吸收与荧光的特性对CS2的一、二阶Stokes谱线阈值的影响.实验发现随溶液浓度(10-8—10-6 mol/L)增加,CS2的一阶Stokes谱线的激发阈值相对变高;并且与纯CS2芯液的受激拉曼散射相比较,在低抽运能量激发下,就观察到CS2的二阶Stokes谱线.这主要是由于在CS2的受激拉曼谱线产生的过程中,β-Carotene的CS2溶液的吸收和荧光共同影响了CS2的一、二阶Stokes谱线的阈值.我们进行了理论上的拟合与分析,其结果与实验符合很好.
关键词:
2受激拉曼散射阈值')" href="#">CS2受激拉曼散射阈值
液芯光纤
吸收与荧光 相似文献
140.
H.T. Huang J.L. He C.H. Zuo H.J. Zhang J.Y. Wang Y. Liu H.T. Wang 《Applied physics. B, Lasers and optics》2007,89(2-3):319-321
We have demonstrated an efficient diode-pumped passively Q-switched Nd:YVO4 laser at 1342 nm by using an uncoated Co2+:LaMgAl11O19 (Co2+:LMA) crystal as the saturable absorber. With the absorbed pump power of 11.7 W, the pulse width could be as low as 42 ns,
with a corresponding average output power of 580 mW. At around 40 kHz repetition rate, the energy of a single Q-switched pulse
was estimated to be about 14.5 μJ and the peak power was 346 W. The passive Q switching operation for the Co2+:LMA in different polarization states was also investigated.
PACS 42.55.-f; 42.55.Xi; 42.60.Gd; 42.70.Mp 相似文献