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排序方式: 共有540条查询结果,搜索用时 46 毫秒
91.
Yasunori Okabe 《Acta Appl Math》2000,63(1-3):307-322
The aim of the present paper is to construct the KM2O-Langevin matrix LM([X,Y]) directly from the correlation matrix function R by using (DDT), (FDT) and (PAC) as an algorithm.  相似文献   
92.
使用ACAT模拟程序计算了不同离子碰撞在单原子材料上的溅射产额.采用山村等人提出的考虑壳层效应的理论屏蔽长度,原子间作用势用Moliére势.并将计算结果与实验数据和山村等的经验公式进行了比较.  相似文献   
93.
This paper is concerned with cross-validation (CV) criteria for choice of models, which can be regarded as approximately unbiased estimators for two types of risk functions. One is AIC type of risk or equivalently the expected Kullback-Leibler distance between the distributions of observations under a candidate model and the true model. The other is based on the expected mean squared error of prediction. In this paper we study asymptotic properties of CV criteria for selecting multivariate regression models and growth curve models under the assumption that a candidate model includes the true model. Based on the results, we propose their corrected versions which are more nearly unbiased for their risks. Through numerical experiments, some tendency of the CV criteria will be also pointed.  相似文献   
94.
We describe preliminary experimental results concerning the operation of a 3 m arm-length Michelson interferometer with two Fabry-Perot cavities whose mirrors and beam splitter are suspended independently by wires. The reflected light beams from the two Fabry-Perot cavities are recombined to obtain interference at a photo-detector; this scheme is necessary for future power-recycled laser interferometers used to detect gravitational waves. The fundamental properties of the interferometer are presented, including the power spectral density of the displacement noise.  相似文献   
95.
A stereoselective synthesis of both syn- and anti-diastereoisomers (3 and 4) was established by a method involving heteroconjugate addition, as the key step, with various nucleophiles such as alkoxyvinyllithiums which can be functionalized after the addition. Two examples with aliphatic and carboxylic groups are demonstrated in high specificity.  相似文献   
96.
The inhibitory effect of poly(2-methacryloyloxyethyl phosphorylcholine-co-butylmetacrylate) (PMB) on the in vitro skin permeation of p-hydroxybenzoic acid and its esters (parabens; methylparaben, ethylparaben, n-propylparaben and n-butylparaben) as model compounds was evaluated. Solubility of the parabens in distilled water was increased by addition of PMB, and the increasing ratio was dependent on the concentration of PMB. The increment of the ratio was more marked in lipophilic parabens than hydrophilic ones. Skin permeability of parabens from their aqueous suspensions was decreased by addition of PMB, and the decreasing ratio was dependent on the PMB concentration. Then, antibacterial effect of parabens of their aqueous solutions was determined with and without PMB by measuring minimum inhibitory concentration (MIC) against E. coli and S. aureus. As results, MIC and antibacterial effect were increased and decreased, respectively, by addition of PMB. The contribution of PMB was more marked in butylparaben than methylparaben. These decreases in skin permeation and antibacterial effect of parabens by PMB are probably due to a higher solubility in water and a lower partition to the skin and bacterial membranes of parabens by addition of PMB.  相似文献   
97.
Yasunori Yamamoto 《Tetrahedron》2004,60(47):10695-10700
Hydroboration of terminal and internal alkenes with pinacolborane (1.2 equiv) was carried out at room temperature in the presence of an iridium(I) catalyst (3 mol%). Addition of dppm (2 equiv) to [Ir(cod)Cl]2 gave the best catalyst for hydroboration of aliphatic terminal and internal alkenes at room temperature, resulting in addition of the boron atom to the terminal carbon of 1-alkenes with more than 99% selectivities. On the other hand, a complex prepared from dppe (2 equiv) and [Ir(cod)Cl]2 resulted in the best yields for vinylarenes such as styrene. These complexes exhibited higher levels of catalyst activity and selectivity than those of corresponding rhodium complexes.  相似文献   
98.
The molecules of 8‐hydroxy­quinolinium‐2‐carboxyl­ate, C10H7NO3, have a planar structure, in which the carboxyl group is ionized and the ring N atom is protonated. The derived nickel(II) complex, bis(8‐hydroxy­quinoline‐2‐carboxyl­ato‐κ3O2,N,O8)­nickel(II) trihydrate, [Ni(C10H6NO3)2]·3H2O, contains an octahedral central NiII ion coordinated by the hydroxyl O atom, the ring N atom and the carboxyl­ate O atom of each of the two tridentate ligands, with a perpendicular orientation of the quinoline rings.  相似文献   
99.
Two new cyclopentenone derivatives, erigerenones A (1) and B (2), and a new cyclooctadienone derivative, erigerenone C (3), were isolated from the aerial parts of Erigeron philadelphicus L. Compound 2 was also isolated from the aerial parts of Erigeron annuus (L.) PERS. and Erigeron sumatrensis RETZ. The structures of 1-3 were elucidated on the basis of their spectral data.  相似文献   
100.
In faded cells of Blepharisma kept in a standard saline solution containing bacteria which had been cultured on agar plates containing glucose and polypepton, threshold light intensity for step-up photophobic response elevated. This result suggests that red pigment (blepharismin) contained in Blepharisma cells is involved in the step-up photophobic response. The pH of the aqueous solution of the red pigment was found to decrease when light was applied, indicating that the pigment releases H+ in response to light stimulation. However, faded pigment preparation by light irradiation did not show pH decrease. In the living cells faded by light irradiation, threshold light intensity for the step-up photophobic response was raised. Results suggest that H+ release from the red pigment induced by light irradiation might be responsible for the step-up photophobic response of the cells.  相似文献   
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