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141.
Beatriz Colomina 《The Journal of Architecture》2013,18(3):205-223
Since the fall of the Wall, there has been heavy international investment in building in East Berlin. On the whole, efforts have remained marginal. Only the western part of East Berlin with its baroque grid has been developed. The central and eastern parts remain as they were. The planning for City East follows four main criteria: to redefine the historic core by structural means without resort to architectural pastiche; to redesign the major roads which occupy much of the historic centre; to restructure the modernism of the GDR capital without demolishing the (mainly prefabricated) buildings; to form an idea of the third town which would be developed by merging existing features with our new plan. 相似文献
142.
Ramón Moreira Francisco Chenlo María D. Torres Beatriz Rama 《Food and Bioproducts Processing》2013,91(1):7-13
Chestnut flour doughs were prepared using chestnut air-dried at 45, 65, and 85 °C with constant load density (8.0 ± 0.6 kg/m2). Mixing curves of doughs using Mixolab® device showed that chestnut flour doughs dried at 85 °C needed more water absorption to reach the target consistency, (1.1 ± 0.07 Nm). Thermorheological properties were evaluated by means of a controlled stress rheometer. All tested doughs showed shear-thinning behaviour in the steady-shear tests (0.001–1 s?1). Oscillatory (1–100 rad s?1 at 0.1% strain), temperature sweep (30–90 °C) and creep-recovery (loading 50 Pa for 60 s) tests showed that flour doughs from chestnuts dried at 85 °C provide interesting properties, particularly remarkable elasticity that is associated with starch gelatinisation. Experimental data were described using various rheological models. 相似文献
143.
Polyazulene films formed by electrochemical oxidation of azulene have been studied as active components in electrochemical capacitors. The film shows reversible electrochemical behavior in the positive potential range and exhibits p-doping properties. The influence of film formation conditions on the films electrochemical properties has been investigated. A strong effect of solvent on the polyazulene deposition has been observed. The highest yield of film deposition was found for dichloromethane. Polyazulene films also exhibit stable voltammetric properties in aprotic solvents. The voltammetric response of the film is affected by the size of the anion of the supporting electrolyte. In solutions containing tetra(alkyl)ammonium perchlorates, tetrafluoroborates or hexafluorophosphates, reversible oxidation of polyazulene is obtained. In the presence of large tetra(phenyl)borate anions, polyazulene is irreversibly oxidized upon electrochemical oxidation. The capacitance properties of these materials have been investigated by cyclic voltammetry and electrochemical impedance spectroscopy. The polyazulene film displays a relatively high specific capacitance close to 400 F g−1. Such high value of Cs locates this material among very good polymeric redox pseudo-capacitors. 相似文献
144.
Heryka Myrna M. Ramalho Susana Casal M. Beatriz Prior Pinto Oliveira 《Food Analytical Methods》2011,4(3):424-430
A simple, fast, sensitive, and environmental friendly micro-method is described for the determination of desmosterol and cholesterol
in milk samples using isocratic normal phase high performance liquid chromatography and diode array detection. After sample
micro-saponification, the chromatographic separation is achieved in 10 min, further reduced to 6 min when only cholesterol
is expected to be present. The method is accurate, presenting cholesterol and desmosterol recoveries >96% and inter-day RSD
lower than 3%. Quantification limits were clearly below the requirements for any milk sample, with 40 and 20 μg/100 mL for
cholesterol and desmosterol, respectively. Several raw and UHT commercial milk samples, infant powder formulas, and human
breast milks were analyzed, with cholesterol and desmosterol (present only in the latter) contents within reported amounts.
The proposed method proved to be simple and feasible for determination of a large number of samples, requiring less solvent
consumption (9–13 mL of hexane for all saponification/extraction/chromatographic steps) and simpler equipment than most ones
reported, and a further possibility of partial solvent recycling due to the isocratic chromatographic mode. 相似文献
145.
J. Borges de Sousa G. Andrade Gonçalves 《Clean Technologies and Environmental Policy》2011,13(2):369-380
Unmanned vehicles have already proved invaluable in environmental field studies by providing levels of spatial–temporal sampling
resolution which could have not been attained before. Recent trends show that the levels of spatial–temporal sampling resolutions
attained with individual vehicles are feasible for wide areas through the operation of persistent vehicle networks. The possibility
of persistent sampling over wide areas has the potential to revolutionize environmental field studies. The roles of unmanned
vehicle systems in future environmental field studies are discussed in the light of the recent technological developments
and trends, along with the major challenges associated to this vision. The discussion is illustrated with examples of developments
from the Underwater Systems and Technologies Laboratory from Porto University, Portugal. 相似文献
146.
Sonia Valle Walter Borges de Oliveira Alexandre Bevilacqua Leoneti Glauco Mateus Magrini CaldoMarcio Mattos Borges de Oliveira 《Biomass & bioenergy》2011,35(7):2608-2618
Energy sources have become a focus of legal, ethical, social and economic pressures due to increasing environmental problems. Nonrenewable energy sources are being increasingly replaced by other sources that are renewable and less pollutive, with technologies aimed at sustainability. Companies that adopt alternative forms of energy will be able to increase their competitiveness and use wastes to generate energy, which is an ecological and economical efficiency approach. In the interior of the state of São Paulo, Brazil, a rural producer of pork crackling and coffee evaluated the entire production cycle of his products and wastes, seeking to achieve energy self sufficiency and identify new possibilities for gains through cost reductions. Biodiesel, soap and detergent are produced with the waste animal fat left from the production of pork crackling. Pig farm wastes become biomass for a biodigester, which produces sufficient biogas to keep the piglets warm, dry the coffee, fry the pork crackling, and generate electricity, among other uses. The biofertilizer produced by the biodigester helps fertilize coffee and corn plantations. The purpose of this article is to demonstrate the ecological and economic feasibility of the project. The research method used here is a case study involving qualitative analyses of environmental and social variables and quantitative analyses of economic variables. It is concluded that the investment made in this project yields excellent returns, with savings of 100% in fuels, 50% in electric energy and 40% in fertilizer, in addition to gains from the products developed with the wastes. 相似文献
147.
Maria Dolores Pastor Ana Nogal Sonia Molina-Pinelo Ricardo Meléndez Beatriz Romero-Romero Maria Dolores Mediano Jose L. López-Campos Rocío García-Carbonero Amparo Sanchez-Gastaldo Amancio Carnero Luis Paz-Ares 《International journal of molecular sciences》2013,14(2):3440-3455
Lung cancer (LC) and chronic obstructive pulmonary disease (COPD) commonly coexist in smokers, and the presence of COPD increases the risk of developing LC. Cigarette smoke causes oxidative stress and an inflammatory response in lung cells, which in turn may be involved in COPD and lung cancer development. The aim of this study was to identify differential proteomic profiles related to oxidative stress response that were potentially involved in these two pathological entities. Protein content was assessed in the bronchoalveolar lavage (BAL) of 60 patients classified in four groups: COPD, COPD and LC, LC, and control (neither COPD nor LC). Proteins were separated into spots by two dimensional polyacrylamide gel electrophoresis (2D-PAGE) and examined by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF/TOF). A total of 16 oxidative stress regulatory proteins were differentially expressed in BAL samples from LC and/or COPD patients as compared with the control group. A distinct proteomic reactive oxygen species (ROS) protein signature emerged that characterized lung cancer and COPD. In conclusion, our findings highlight the role of the oxidative stress response proteins in the pathogenic pathways of both diseases, and provide new candidate biomarkers and predictive tools for LC and COPD diagnosis. 相似文献
148.
Beatriz López-Walle Michaël Gauthier Nicolas Chaillet 《International Journal of Thermal Sciences》2010,49(11):2108-2116
Thermal actuators are extensively used in microelectromechanical systems (MEMS). Heat transfer through and around these microstructures are very complex. Knowing and controlling them in order to improve the performance of the micro-actuator, is currently a great challenge. This paper deals with this topic and proposes a dynamic thermal modelling of thermal micro-actuators. Thermal problems may be modelled using electrical analogy. However, current equivalent electrical models (thermal networks) are generally obtained considering only heat transfers through the thickness of structures having considerable height and length in relation to width (walls). These models cannot be directly applied to micro-actuators. In fact, micro-actuator configurations are based on 3D beam structures, and heat transfers occur through and around length. New dynamic and static thermal networks are then proposed in this paper. The validities of both types of thermal networks have been studied. They are successfully validated by comparison with finite elements simulation and analytical calculations. 相似文献
149.
Borges C.L.T. Falcao D.M. Mello J.C.O. Melo A.C.G. 《Power Systems, IEEE Transactions on》2001,16(2):203-209
This paper describes two parallel methodologies for composite reliability evaluation using sequential Monte Carlo simulation. The methodologies are based on coarse grain asynchronous implementations. In the first methodology, a complete simulation year is analyzed on a single processor and the many simulated years necessary for convergence are analyzed in parallel. In the second methodology, the adequacy analysis of the system operating states within the simulated years is performed in parallel and the convergence is checked on one processor at the end of each simulated year. The methodologies are implemented on a 10 nodes IBM RS/6000 SP scalable distributed memory parallel computer and on a network of 8 IBM RS/6000 43P workstations. The results obtained in tests with actual power system models showed high speedup and efficiency on both parallel platforms 相似文献
150.
Márcia Beatriz Reis Fróes Luis Fabrício Santana Santos Sandro Navickiene 《Food Analytical Methods》2013,6(1):328-333
An extraction method based on matrix solid phase dispersion was developed to determine bromuconazole, fenbuconazole, parathion-methyl, kresoxim-methyl, and teflubenzuron in açai using liquid chromatography with ultraviolet diode array detector. The best results were obtained using 1.0 g of açai, 3.0 g of neutral alumina as the dispersant sorbent, and cyclohexane/ethyl acetate (1:1, v/v, 20 mL) as an eluting solvent. The method was validated using açai samples fortified with pesticides at three concentration levels (0.25, 0.5, and 1.0 mg kg?1). Average recoveries (seven replicates) ranged from 66 to 119 %, with relative standard deviations between 1.4 and 20 %. The detection and quantification limits for açai ranged from 0.02 to 0.05 mg kg?1 and from 0.05 to 0.1 mg kg?1, respectively. 相似文献