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de Oliveira Cristina Soltovski Bet Camila Delinski Bisinella Radla Zabian Bassetto Waiga Lucas Henrique Colman Tiago André Denck Schnitzler Egon 《Journal of Thermal Analysis and Calorimetry》2018,133(3):1491-1498
Journal of Thermal Analysis and Calorimetry - Samples of potato starch (PS), sweet potato starch (SPS) and their binary mixtures, with moisture levels of 10, 15 and 20% (db), were submitted to... 相似文献
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We study the semiparametric estimation of stochastic differential equations employing methods based on moment conditions, comparing the finite sample and robustness properties of generalized method of moments, empirical likelihood and minimum contrast methods using unconditional and conditional formulations of moment conditions. The results obtained indicate that the estimators proposed, particularly, the estimators based on exponential tilting, obtain better results than those of the generalized methods of moments normally used to estimate stochastic differential equations. This conclusion is mainly derived from the robustness properties of this method in the presence of problems of incorrect specification. 相似文献
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One of the key parameters in modeling capital budgeting decisions for investments with embedded options is the project volatility. Most often, however, there is no market or historical data available to provide an accurate estimate for this parameter. A common approach to estimating the project volatility in such instances is to use a Monte Carlo simulation where one or more sources of uncertainty are consolidated into a single stochastic process for the project cash flows, from which the volatility parameter can be determined. Nonetheless, the simulation estimation method originally suggested for this purpose systematically overstates the project volatility, which can result in incorrect option values and non-optimal investment decisions. Examples that illustrate this issue numerically have appeared in several recent papers, along with revised estimation methods that address this problem. In this article, we extend that work by showing analytically the source of the overestimation bias and the adjustment necessary to remove it. We then generalize this development for the cases of levered cash flows and non-constant volatility. In each case, we use an example problem to show how a revised estimation methodology can be applied. 相似文献
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The position of a graphene nanoribbon on a solid substrate allows the chemical modification of only one of the nanoribbon sides. A method was proposed that enables the chemical modification of the other side, too. It was numerically modeled how a nanoribbon separated from a substrate rolls up into a roll and how the roll unrolls on a flat substrate. The dependences of the number of coils and the radii of rolls forming by hydrogenation on the nanoribbon length and width were determined. 相似文献
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Helberth Júnnior Santos Lopes Lucas Rodrigues Ramos Edson Luiz Silva 《Applied biochemistry and biotechnology》2017,183(3):712-728
This study evaluated the production of hydrogen and propionic acid in an expanded granular sludge bed (EGSB) reactor by co-fermentation of cheese whey (CW) and crude glycerol (CG). The reactor was operated at hydraulic retention time (HRT) of 8 h by changing the CW/CG ratio from 5:1 to 5:2, 5:3, 5:4, and 5:5. At the ratio of 5:5, HRT was reduced from 8 to 0.5 h. The maximum hydrogen yield of 0.120 mmol H2 g COD?1 was observed at the CW/CG ratio of 5:1. Increasing the CG concentration repressed hydrogen production in favor of propionic acid, with a maximum yield of 6.19 mmol HPr g COD?1 at the CW/CG ratio of 5:3. Moreover, by reducing HRT of 8 to 0.5 h, the hydrogen production rate was increased to a maximum value of 42.5 mL H2 h?1 L?1at HRT of 0.5 h. The major metabolites were propionate, 1,3-propanediol, acetate, butyrate, and lactate. 相似文献
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Plínio T. Berardo Maurício S. Abrao Maísa L.S. Souza Daniel E. Machado Luiz-Cláudio F. Silva Luiz E. Nasciutti 《Micron (Oxford, England : 1993)》2009,40(5-6):639-645
The composition of sulfated glycosaminoglycans (GAGs) and the tissue distribution of chondroitin sulfate (CS) were analyzed in deeply infiltrating endometriosis (DIE) of rectosigmoid, using metachromatic staining, and biochemical analysis employing electrophoresis before and after specific enzymatic or chemical degradations, and immunostaining with an antibody against CS. The sulfated GAGs were characterized as dermatan sulfate (DS), heparan sulfate (HS) and CS; and DS strongly predominated compared to HS and CS. Immunostaining procedures showed that CS was concentrated in the endometriosis foci, distributed throughout the stroma around the glands. This is the first report describing the composition of sulfated GAGs and the tissue location of CS in DIE by means of histochemical, biochemical and immunohistochemical analyses. These results confirmed that in DIE of rectosigmoid, as in eutopic endometrium [Nasciutti, L.E., Ferrari, R., Berardo, P.T., Souza, M.L.S., Takiya, C.M., Borojevic, R., Abrao, M.S., Silva, L.C.F., 2006. Distribution of chondroitin sulfate in human endometrium. Micron 37, 544–550], CS was the dominant sulfated GAG in stroma of the lesion foci. 相似文献