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111.
Roelof Helmers Ričardas Zitikis 《Annals of the Institute of Statistical Mathematics》1999,51(2):265-280
Under the presence of only one realization, we consider a computationally simple algorithm for estimating the intensity function of a Poisson process with exponential quadratic and cyclic of fixed frequency trends. We argue that the algorithm can successfully be used to estimate any Poisson intensity function provided that it has a parametric form. 相似文献
112.
A.Y. Leinekugel-le-Cocq-Errien S. Jobic M. Evain F. Bart 《Journal of solid state chemistry》2007,180(1):322-330
X-ray patterns of the Ba1Cs0.28Fe0.82Al1.46Ti5.72O16 compound evidence two wide peaks at low angle in addition to the well defined peaks of the I4/m hollandite structure type. Two hypotheses have been explored to account for these features: the coexistence of the hollandite phase with an amorphous phase and the appearance of a commensurate or incommensurate modulated structure associated with a cationic ordering, as proposed in the literature. Actually, even if the amorphous phase quantification by the Rietveld method reveals about 15 wt% of non-crystalline phase in some of the powdered sample, the origin of the two wide peaks was found to stem from the incommensurate modulated character of the hollandite structure type (super space group I4/m(0 0 γ)0 0) with a distribution of the modulation wavevectors presumably related to slight chemical composition changes. 相似文献
113.
《Arabian Journal of Chemistry》2022,15(4):103718
The present study attempts to prepare Al-substituted α-Ni(OH)2 and Al-substituted α-Ni(OH)2 with modified interlayer anions by directly immersing pure α-Ni(OH)2 into AlCl3-containing solutions. XRD and FT-IR analysis demonstrated Al-substituted α-Ni(OH)2 can be prepared directly by soaking pure α-Ni(OH)2 into AlCl3 solution. Al-substituted α-Ni(OH)2 with S2O32? as the primary anion in the interlayer can be obtained by immersing pure α-Ni(OH)2 into AlCl3-Na2S2O3 solution. The analysis of Al content in samples demonstrated the Al content in the Al-substituted α-Ni(OH)2 was regulated by adjusting the molar ratio of pure α-Ni(OH)2 soaked in the solution and Al3+ dissolved in the solution. The Al element entered the lattice of pure α-Ni(OH)2 through a process of pure α-Ni(OH)2 dissolved followed by the precipitation of Al3+, Ni2+ and OH?. The S2O32? entered the interlayer of Al-substituted α-Ni(OH)2 through the formation process of the Al-substituted α-Ni(OH)2 or though ion exchange with the intercalated Cl?. The strongly alkaline solution soaking results demonstrated that Al-substituted α-Ni(OH)2 prepared by soaking pure α-Ni(OH)2 into AlCl3-containing solutions could preliminary get stabilized in the strongly alkaline solution. 相似文献
114.
Nagatani H Suzuki S Fermín DJ Girault HH Nakatani K 《Analytical and bioanalytical chemistry》2006,386(3):633-638
The transfer mechanism of an amphoteric rhodamine, sulforhodamine 101 (SR101), across the polarized water/1,2-dichloroethane
(DCE) interface was investigated using cyclic voltammetry, differential voltfluorometry and potential-modulated fluorescence
(PMF) spectroscopy. The voltammetric response for the ion transfer of SR101 monoanion from water to DCE was observed as the
diffusion-controlled transfer process. An unusual voltammetric response was found at 0.15 V more negative than the formal
transfer potential of SR101−
in the cyclic voltammogram and voltfluorogram. The frequency dependence of the PMF responses confirmed the presence of the
adsorption processes at negative potentials. In addition, a further transient adsorption step was uncovered at The interfacial mechanism of SR101 is discussed by comparing the results obtained from each technique. 相似文献
115.
We consider the beam orientation optimization (BOO) problem for total marrow irradiation (TMI) treatment planning using intensity modulated radiation therapy (IMRT). Currently, IMRT is not widely used in TMI treatment delivery; furthermore, the effect of using non-coplanar beam orientations is not known. We propose and implement several variations of a single neighborhood search algorithm that solves the BOO problem effectively when gantry angles and couch translations are considered. Our work shows that the BOO problem for TMI cases can be solved in a clinically acceptable amount of time and leads to treatment plans that are more effective than the conventional approach to TMI. 相似文献
116.
Micro-thermal analysis combines the imaging facility of scanning probe microscopy with the ability to characterize, with high
spatial resolution, the thermal behavior of materials. A sample may be visualized according to its surface topography and
also its relative thermal conductivity. Areas of interest may then be selected and localized thermal analysis (TMA and modulated
temperature DTA) performed. Applications of this new technique to study semiconductors, polymer blends and biological specimens
are described.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
117.
Gamlin C. Markovic M. G. Dutta N. K. Choudhury N. R. Matisons J. G. 《Journal of Thermal Analysis and Calorimetry》2000,59(1-2):319-336
Effects of ethylene content and maleated EPDM content on the thermal stability and degradation kinetics of ethylene propylene diene monomer (EPDM) have been studied using high resolution thermogravimetric analysis (Hi-Res TGA) and Modulated TGA (MTGA). Modulated TGA shows that EPDM degradation is complex, with activation energy of degradation increasing throughout the degradation. Values from both dynamic and constant heating rate experiments are in good agreement with each other and with the literature value. However, the dynamic heating rate experiment shows that if the difference of peak temperature of components in a system is less than 5°C, Hi-Res TGA does not resolve them.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
118.
Experiments using a commercial modulated DSC (MDSC) for the measurement of specific heat capacity of a sample have been carried out. It is found that because the amplitude of heat flow of MDSC is a complicated non-linear function of various experimental conditions such as the modulation frequency and the heat capacities of a sample and pan, the methodology of heat capacity determination using an MDSC in a single run has not been justified. The experimental results, on the other hand, agree with the theoretical equation of one of the authors. It is therefore concluded that the capabilities of MDSC should be further examined. 相似文献
119.
Nia Petrova Momchil Paunov Petar Petrov Violeta Velikova Vasilij Goltsev Sashka Krumova 《Molecules (Basel, Switzerland)》2021,26(19)
Single-walled carbon nanotubes (SWCNT) have recently been attracting the attention of plant biologists as a prospective tool for modulation of photosynthesis in higher plants. However, the exact mode of action of SWCNT on the photosynthetic electron transport chain remains unknown. In this work, we examined the effect of foliar application of polymer-grafted SWCNT on the donor side of photosystem II, the intersystem electron transfer chain and the acceptor side of photosystem I. Analysis of the induction curves of chlorophyll fluorescence via JIP test and construction of differential curves revealed that SWCNT concentrations up to 100 mg/L did not affect the photosynthetic electron transport chain. SWCNT concentration of 300 mg/L had no effect on the photosystem II donor side but provoked inactivation of photosystem II reaction centres and slowed down the reduction of the plastoquinone pool and the photosystem I end acceptors. Changes in the modulated reflection at 820 nm, too, indicated slower re-reduction of photosystem I reaction centres in SWCNT-treated leaves. We conclude that SWCNT are likely to be able to divert electrons from the photosynthetic electron transport chain at the level of photosystem I end acceptors and plastoquinone pool in vivo. Further research is needed to unequivocally prove if the observed effects are due to specific interaction between SWCNT and the photosynthetic apparatus. 相似文献
120.
Karger-Kocsis J. Moskala E. J. Shang P. P. 《Journal of Thermal Analysis and Calorimetry》2001,63(3):671-678
The toughness of amorphous copolyester sheets was assessed by the essential work of fracture (EWF) concept. While the yielding-related
work of fracture terms did not change significantly, the necking-related parameters strongly decreased with decreasing entanglement
density of the copolyesters having different amounts of cyclohexylenedimethylene (CHDM) units in their backbones. Furthermore, copolyesters with high CHDM content and thus less entanglement density showed full recovery of the necked region beyond the glass transition temperature,
i.e. the ‘plastic’ zone in the related specimens formed by cold drawing and not by true plastic deformation. By contrast,
the copolyester with negligible amount of CHDM did not show this shape recovery. Modulated differential scanning calorimetry (MDSC) revealed that the necking in the latter
system was accompanied by strain-induced crystallization. The superior work hardening in the necking stage of the respective
poly(ethylene terephthalate) (PET) specimens can thus be ascribed to stretching of the entanglement network with superimposed crystallization.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献