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991.
In this paper, the boundedness in Lebesgue spaces of commutators and multilinear commutators generated by θ-type Calderón-Zygmund operators with RB MO(μ) functions on non-homogeneous metric measure spaces is obtained.  相似文献   
992.
单镜头三维粒子成像测速   总被引:2,自引:2,他引:2  
刘颂  张金钟 《实验力学》1994,9(3):225-231
本文提出了一种用单镜头进行三维流场测量的方法,建立了包括摄录系统、数字图象处理及识别系统及流动装置的3D-SCPIV系统。完成了现有条件下的原理性定量测量实验。  相似文献   
993.
994.
A chemical investigation of AcOEt‐soluble portion of the 95% EtOH extract of the aerial parts of Clerodendranthus spicatus led to the isolation and characterization of a new diterpenoid, named clerospicasin J ( 1 ). Structure elucidation of 1 was achieved by spectroscopic analyses, including 2D‐NMR. The diterpenoid 1 exhibited significant inhibitory activity on the proliferation of the SKOV3 cell lines. Moreover, the cytotoxicity of 1 against SKOV3 cells was related to apoptotis as confirmed by DAPI (=2‐(4‐amidinophenyl)‐1H‐indole‐6‐carboxamidine) nuclear staining and flow cytometry.  相似文献   
995.
Lately, profile monitoring has received considerable attention in the statistical process control research field. This paper proposes a novel monitoring framework for the reflow process data, which uses two goodness‐of‐fit criteria to select the change points in the mixture polynomial model. Among change points, the mixture second‐order polynomials are utilized to piecewisely approximate the nonlinear profile data of the reflow process. The well‐known Hotelling T2 and proposed EWMA4 control charts are then employed to monitor the parameter estimates. The experimental results demonstrate that the proposed monitoring framework presents better performances in detecting outlying profiles than the conventional methods in phase I. In phase II, the performance of the proposed framework is assessed in terms of the out‐of‐control average run length. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
996.
The reaction of Ni(ClO4)2 · 6H2O with 3‐ethoxy‐2‐hydroxybenzaldehyde (Hemp), methylamine, and NaN3 in DMF solution, under solvothermal conditions, leads to the formation of the heterotetrametallic cluster [Ni2Na21,1,1‐N3)2(emimp)4(DMF)2] ( I ) (emimp = 2‐ethoxy‐6‐formyl‐phenolate anion, DMF = N,N‐dimethyl‐formamide). Compound I displays dominant ferromagnetic interactions through μ1,1,1‐N3 bridging mode.  相似文献   
997.
998.
999.
Reported here is a facile synthesis of nanoporous polymer chalk for painting superhydrophobic surfaces. Taking this nanoporous polymer as a media, superhydrophobicity is rapidly imparted onto three typical kinds of substrates, including paper, transparent polydimethylsiloxane (PDMS), and finger skin. Quantitative characterization showed that the adhesion between the water droplet and polymer-coated substrates decreased significantly compared to that on the original surface, further indicating the effective wetting mode transformation. The nanoporous polymer coating would open a new door for facile, rapid, safe, and larger scale fabrication of superhydrophobic surfaces on general substrates.  相似文献   
1000.
The gas-phase studies of transition-metal oxides continue to attract interest as such oxides are being used as catalysts in various oxidation processes. In this paper, singly negatively charged heteropolyoxotungstate and isopolyoxotungstate ion clusters were produced from Keggin-type polyoxotungstates by matrix-assisted laser desorption/ionization Fourier transform ion cyclotron resonance mass spectrometry (MALDI-FTICR MS). It was found that the ion series [(PO(3))(WO(3))(n)](-), [(WO(3))(n)](-) and [(OH)(WO(3))(n)](-) were the main fragment ions in the mass spectra and the matrix greatly influenced the resulting cluster ion abundances. [(PO(3))(WO(3))(3)](-), [(WO(3))(3)](-) and [(OH)(WO(3))(4)](-) were the most intense ions in each series when 2-(4-hydroxyphenylazo)benzoic acid was the matrix, whereas [(PO(3))(WO(3))(4)](-), [(WO(3))(6)](-) and [(OH)(WO(3))(4)](-) were the most intense when dithranol (DIT) was the matrix. In addition, a new kind of hybrid ion [W(2)C(14)H(7)O(8)](-) was produced through the reaction of DIT and [(OH)(WO(3))](-) in the plume of the gas phase. These results highlight the utility of the MALDI-FT method for obtaining novel ion clusters and also show the stability of these clusters.  相似文献   
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