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This paper investigates the combustion characteristics of 12 wood species natural to Brazil. A mass loss cone calorimeter was used to obtain the properties associated with (i) heat release rate (HRR), peak HRR, and total heat released; (ii) total mass loss and mass loss rate; (iii) average effective heat of combustion; and (iv) time to ignition, time of pyrolysis and temperature of ignition. The samples used in this work were as follows: (i) prepared in accordance to ISO 5660‐1:2002; (ii) oven dried; (iii) irradiated with a constant heat flux of 50 kW/m2; and (iv) exhibit wood fiber orientation in a plane orthogonal to the flux incidence. Finally, the paper explores the possibility of linking the obtained combustion properties with the density and classes of selected wood species. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Isensee Leandro José Pinheiro Adilson Detzel Daniel Henrique Marco 《Water Resources Management》2021,35(5):1499-1512
Water Resources Management - Increasing global trends in time series of annual maximum daily streamflow (AMX) raise the concern that the safety of dams and other sensitive structures is... 相似文献
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Carlos A. da Silva Henrique B. Pereira Maria E. S. Taqueda Zehbour Panossian 《工业材料与腐蚀》2021,72(11):1796-1807
In the offshore oil and gas industry, mainly focusing on the use of rigid or flexible pipes of subsea infrastructure applied to risers or flowlines, one of the greatest difficulties is the interpretation of the combined effects of the various correlated phenomena (hydrodynamic effects of intermittent flow, the effects of corrosivity of the environment in addition to variations in pressure, temperature, and dynamic loading). On the basis of this scenario, defining the degree of severity of each of the correlated system variables becomes of fundamental importance for establishing reliable criteria for selecting materials for subsea application. The established flow pattern directly affects the corrosion rate (or the pipe material mass loss), but the balance of other variables including possible changes in the physical and transported fluid chemical properties may increase the damage up to an order of magnitude, which is a piece of information normally not foreseen in design criteria. Therefore, to improve the understanding of the corrosion study influenced by multiphase flow, a testing loop was designed and assembled at the Corrosion and Protection Laboratory of the Institute for Technological Research, in which API X80 steel coupons were positioned in locations with a 0° and 45° inclinations. Tests were conducted by varying the partial pressure of the gaseous phase containing blends of CO2 and H2S with N2 balance, mixed with the liquid phase containing light oil and heavy oil in water with salinity (NaCl)-simulating oil well conditions with 80% water cut. The main objective of this study is to establish models that can predict the corrosion intensity in conditions close to those obtained experimentally. To achieve results, the multiple regression and Box–Cox transformation methods were applied. These models will make possible damage prediction and optimization of matrix parameters for the multiphase-loop test. 相似文献
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Daniele da Silva Bastos Maria do Pilar Gonçalves Cristina Tristão de Andrade Kátia Gomes de Lima Araújo Maria Helena Miguez da Rocha Leão 《Food and Bioproducts Processing》2012,90(4):683-692
The aim of this work was to obtain a new stable food product from cashew apple juice encapsulated by spray-drying technique using chitosan–whey protein isolate systems. The materials were evaluated according to their physicochemical stability during storage at different conditions and characterized with respect to their particle size distribution and structure. Encapsulated commercial and natural juices showed homogenous and unimodal particle size distribution with diameters ranging from 0.2 to 5.0 μm and from 0.2 to 40.0 μm, respectively. Both juices demonstrated higher physicochemical stability for vitamin C and color measurements than their respective non-encapsulated juices. X-ray diffractograms evidenced that the powder juices after the 140th day of storage were still in amorphous state. These results indicate that the new product was effective in protecting sensitive compounds present in the food matrix and it was also able to remain stable throughout the study period. 相似文献
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Modulation of Biodistribution,Pharmacokinetics, and Photosensitivity with the Delivery Vehicle of a Bacteriochlorin Photosensitizer for Photodynamic Therapy
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Raquel Saavedra Luis B. Rocha Dr. Janusz M. Dąbrowski Prof. Luis G. Arnaut 《ChemMedChem》2014,9(2):390-398
Intravenous (i.v.) formulations with various amounts of organic solvents [PEG400, propylene glycol (PG), cremophor EL (CrEL)] were used to deliver a fluorinated sulfonamide bacteriochlorin to mice, rats, and minipigs. Biodistribution studies in mice showed that a low‐content CrEL formulation combines high bioavailability with high tumor‐to‐muscle and tumor‐to‐skin ratios. This formulation was also the most successful in the photodynamic therapy of mice with subcutaneously implanted CT26 murine colon adenocarcinoma tumors. Pharmacokinetic studies in mice and minipigs revealed that with the same low CrEL formulation, the half‐life of the photosensitizer in the central compartment was longer in minipigs. Differences in biodistribution with the various formulations, and in pharmacokinetics between the two animal species with the same formulation, are attributed to the interaction of the formulations with low‐density lipoproteins (LDLs). Skin photosensitivity studies in rats showed that 30 min exposure of the skin to a solar simulator 7 days after i.v. administration of the fluorinated sulfonamide bacteriochlorin at 1 mg kg?1 did not elicit significant skin reactions. 相似文献
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António Abreu Álvaro Rocha João Vidal de Carvalho Manuel Pérez Cota 《Telematics and Informatics》2017,34(6):861-877
This article presents the first phase of a research project whose purpose is to introduce a new form of collaboration and communication between the school and the family through an Electronic Booklet (EB). The EB was developed due to the increasing necessity of collaboration between the school and the family, promoting the teaching-learning process and educational success, supported by information and communication technologies. These conclusions and justifications were derived from a survey based in a questionnaire applied to guardians and teachers of several private and public Portuguese schools of the primary and secondary education level. Both groups – guardians and teachers stressed the importance of communication between school and family and expressed interest in the EB as a communication tool. The analysis of the survey results made possible the construction of an Electronics Booklet prototype. 相似文献