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排序方式: 共有150条查询结果,搜索用时 609 毫秒
41.
Eckhard Otto Frank Stratmann Heinz Fissan Srinivas Vemury Sotiris E. Pratsinis 《Particle & Particle Systems Characterization》1994,11(5):359-366
A log-normal model, based on the extended SIMPLER-algorithm utilizing the Modal Aerosol Dynamics Modelling Technique, and a sectional model are compared for Brownian coagulation in the transition regime. The models are in good agreement with respect to the calculated particle size distribution moments. Applying the log-normal model a simple coagulation model consisting of a closed set of five equations is developed that does not require the solution of ordinary diferential equations. 相似文献
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Mehring M Gabriele G Hadjikakou S Schürmann M Dakternieks D Jurkschat K 《Chemical communications (Cambridge, England)》2002,(8):834-835
The crystal structure of the novel methylene-bridged tetraorganodistannoxane ([Ph(HO)SnCH2Sn(I)Ph]O)4 (1) depends on the solvent it is crystallised from and is controlled by hydrogen bridges and interhalogen interactions. 相似文献
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45.
Liu J Miller WH Fanourgakis GS Xantheas SS Imoto S Saito S 《The Journal of chemical physics》2011,135(24):244503
The dynamical properties of liquid water play an important role in many processes in nature. In this paper, we focus on the infrared (IR) absorption spectrum of liquid water based on the linearized semiclassical initial value representation (LSC-IVR) with the local Gaussian approximation (LGA) [J. Liu and W. H. Miller, J. Chem. Phys. 131, 074113 (2009)] and an ab initio based, flexible, polarizable Thole-type model (TTM3-F) [G. S. Fanourgakis and S. S. Xantheas, J. Chem. Phys. 128, 074506 (2008)]. Although the LSC-IVR (LGA) gives the exact result for the isolated three-dimensional shifted harmonic stretching model, it yields a blueshifted peak position for the more realistic anharmonic stretching potential. By using the short-time information of the LSC-IVR correlation function; however, it is shown how one can obtain more accurate results for the position of the stretching peak. Due to the physical decay in the condensed phase system, the LSC-IVR (LGA) is a good and practical approximate quantum approach for the IR spectrum of liquid water. The present results offer valuable insight into future attempts to improve the accuracy of the TTM3-F potential or other ab initio-based models in reproducing the IR spectrum of liquid water. 相似文献
46.
Stavros D. Peroukidis Alexandros G. Vanakaras Sotiris Droulias Demetri J. Photinos 《Liquid crystals》2013,40(10):1430-1435
We study theoretically the optical properties of a two-dimensional lattice of metallic (gold) nanorods immersed within a nematic liquid crystal (NLC) strongly anchored to the surface of the nanorods. The distribution of the director field of the NLC is found by minimising the corresponding total free energy via simulated annealing. Optical properties such as transmittance, reflectance and absorbance of the structure are found by employing a hybrid discrete-dipole approximation/layer-multiple-scattering technique. We show, in particular, that when the NLC is strongly anchored to the nanorods, light absorbance is more efficient compared to the case where the liquid crystal (LC) is aligned by application of an external field. Also, the alignment of the LC molecules via an external field leads to a significant shift of the surface-plasmon resonance of the gold nanorods relative to the strong-anchoring case, an effect which can be exploited in switching applications. We also report that the rate of light absorption is a non-monotonic function of the height of nanorods due to the guiding of EM waves taking place for long enough nanorods. 相似文献
47.
Petros Karalis Anastasia Elektra Poutouki Theodora Nikou Maria Halabalaki Charalampos Proestos Effie Tsakalidou Sofia Gougoura George Diamantopoulos Maria Tassi Elissavet Dotsika 《Molecules (Basel, Switzerland)》2020,25(24)
In recent years, isotopic analysis has been proven a valuable tool for the determination of the origin of various materials. In this article, we studied the 18O and 13C isotopic values of 210 olive oil samples that were originated from different regions in Greece in order to verify how these values are affected by the climate regime. We observed that the δ18O isotopic values range from 19.2 ‰ to 25.2 ‰ and the δ13C values range from −32.7 ‰ to −28.3 ‰. These differences between the olive oils’ isotopic values depended on the regional temperature, the meteoric water, and the distance from the sea. Furthermore, we studied the 13C isotopic values of biophenolic extracts, and we observed that they have same capability to differentiate the geographic origin. Finally, we compared the isotopic values of Greek olive oils with samples from Italy, and we concluded that there is a great dependence of oxygen isotopes on the climatic characteristics of the different geographical areas. 相似文献
48.
Photothermal Killing of Cancer Cells by the Controlled Plasmonic Coupling of Silica‐Coated Au/Fe2O3 Nanoaggregates 下载免费PDF全文
Georgios A. Sotiriou Fabian Starsich Athanasia Dasargyri Moritz C. Wurnig Frank Krumeich Andreas Boss Jean‐Christophe Leroux Sotiris E. Pratsinis 《Advanced functional materials》2014,24(19):2818-2827
Tumor ablation by thermal energy via the irradiation of plasmonic nanoparticles is a relatively new oncology treatment. Hybrid plasmonic‐superparamagnetic nanoaggregates (50–100 nm in diameter) consisting of SiO2‐coated Fe2O3 and Au (≈30 nm) nanoparticles were fabricated using scalable flame aerosol technology. By finely tuning the Au interparticle distance using the SiO2 film thickness (or content), the plasmonic coupling of Au nanoparticles can be finely controlled bringing their optical absorption to the near‐IR that is most important for human tissue transmittance. The SiO2 shell facilitates also dispersion and prevents the reshaping or coalescence of Au particles during laser irradiation, thereby allowing their use in multiple treatments. These nanoaggregates have magnetic resonance imaging (MRI) capability as shown by measuring their r2 relaxivity while their effectiveness as photothermal agents is demonstrated by killing human breast cancer cells with a short, four minute near‐IR laser irradiation (785 nm) at low flux (4.9 W cm‐2). 相似文献
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50.
Universal Laurent series where the universal approximation is valid on the boundary of the multiple connected open Ω appears
for the first time in [2]. We show that it is possible to demand universal approximation only to a part of the boundary while
on the remaining part the universal function can be smooth.
Received: 29 May 2007 相似文献