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111.
Pablo Monetta Luis Bueno Vanina Cornejo Fernando González-Aubone Germán Babelis 《The International journal of environmental studies》2013,70(4):578-588
Two-phase olive oil mills generate a semi-solid waste made of olive pulp, olive stone, and vegetation water commonly called ‘alperujo’. Lack of disposal alternatives drives many Argentinean olive oil producers to apply it directly as soil amendment to the olive orchards. Even though this practice has been widely evaluated in Mediterranean countries, there is little agreement on the environmental impact that it may produce. In this work a surface layer of alperujo was applied to a high-density, drip-irrigated olive orchard, and different parameters were monitored. This report summarises the dynamics of soil chemical properties during the first 200 days after application. The results obtained showed that soil amended with alperujo increased total organic matter (OM), nitrogen (N) and available potassium (K), without affecting soil electrical conductivity (EC), pH and C/N ratio. The results suggest that surface application of alperujo may represent an attractive alternative to disposal under conservationist management. Further research evaluating long term effects on chemical and biological indicators must be performed to ensure the sustainability of alperujo as soil amendment. 相似文献
112.
Montmorillonite as support for peroxide in the melt grafting of maleic anhydride onto polypropylene 下载免费PDF全文
Grafting of maleic anhydride onto polypropylene was performed in a Haake torque rheometer, in the presence of organically modified montmorillonite, MMT (used as support for the peroxide), according to a 23 factorial design, where the maleic anhydride concentration (CMA), peroxide concentration (Cper) and reaction time (tr) were varied. For comparison, the reaction in the absence of MMT was also conducted. Polypropylene degradation was assessed by parallel plate rheometry and size exclusion chromatography (SEC) and percentage of reacted maleic anhydride (%MAg) was obtained by titration and FTIR spectroscopy. The results showed differences in both systems, conventional and in the presence of MMT. The structure of polypropylene grafted with maleic anhydride, PP‐g‐MA, indicates longer branches are formed in the presence of MMT compared to in its absence, demonstrated by FTIR analysis. As in conventional reaction systems, an increase in Cper caused an increase in %MAg and a reduction in molar mass. The variable CMA showed to be not significant in the grafting reaction in the presence of MMT, even at high DCP levels, at a 5% significance level. On the other hand, increase in CMA resulted in significant increase in viscosity. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44134. 相似文献
113.
The effect of different porous media on moisture loss and oil absorption profiles during frying using glass micromodels 下载免费PDF全文
Pablo Cortés Guillermo Badillo Luis Segura Pedro Bouchon 《American Institute of Chemical Engineers》2016,62(3):629-638
Microstructure plays a key role in oil absorption during frying. The aim of this work was to improve our understanding of the relationship between microstructure and oil absorption, through the use of glass micromodels to obtain evidence of transport phenomena in three porous networks. Micromodels were saturated with water and partially immersed in oil at 190°C. Moisture and oil profiles were imaged to get water and oil saturation maps. Image and fractal analyses were performed to describe the morphology of the evaporation and oil fronts. Results showed that higher porosity facilitated the moisture removal and promoted greater oil absorption during cooling. The fractal dimension showed that microstructures with a relatively high number of fine capillaries were less stable and propitiated fingering during the advance of the evaporation front. In all matrices, the disruption of the surface oil film due to air penetration was a critical factor to stop oil imbibition. © 2015 American Institute of Chemical Engineers AIChE J, 62: 629–638, 2016 相似文献
114.
The discovery of various driver pathways and targeted small molecule agents/antibodies have revolutionized the management of metastatic breast cancer. Currently, the major targets of clinical utility in breast cancer include the human epidermal growth factor receptor 2 (HER2) and epidermal growth factor receptor (EGFR), vascular endothelial growth factor (VEGF) receptor, mechanistic target of rapamycin (mTOR) pathway, and the cyclin-dependent kinase 4/6 (CDK-4/6) pathway. Brain metastasis, however, remains a thorn in the flesh, leading to morbidity, neuro-cognitive decline, and interruptions in the management of systemic disease. Approximately 20%–30% of patients with metastatic breast cancer develop brain metastases. Surgery, whole brain radiation therapy, and stereotactic radiosurgery are the traditional treatment options for patients with brain metastases. The therapeutic paradigm is changing due to better understanding of the blood brain barrier and the advent of tyrosine kinase inhibitors and monoclonal antibodies. Several of these agents are in clinical practice and several others are in early stage clinical trials. In this article, we will review the common targetable pathways in the management of breast cancer patients with brain metastases, and the current state of the clinical development of drugs against these pathways. 相似文献
115.
Naveen Kumar Chenna Pablo Piovano Christian Järnefelt Tapani Vuorinen 《木材化学与工艺学杂志》2016,36(5):318-328
An oxygen delignified eucalyptus kraft pulp was bleached by applying a catalytic amount of a tertiary amine, 1,4-diazabicyclo[2,2,2]octane, and hypochlorous acid at varying pH, temperature, and time. The bleaching filtrate was analyzed for chloroform and AOX and the pulp for residual lignin, hexenuronic acid, and OX. In comparison with chlorine dioxide bleaching, the novel catalytic bleaching (pH < 6) generated only traces of chloroform and low contents of AOX and OX. Separate catalytic oxidations of authentic hexenuronic acid showed that it was a major precursor of chloroform. The results demonstrate a practical way to reduce organochlorine formation in pulp bleaching and provide new understanding on the reaction pathways that yield chloroform. 相似文献
116.
Sub-micronic, spherical Y2O3:Yb/Er particles comprising clustered nano-units (70 nm) were prepared via ultrasonic spray pyrolysis from pure nitrate precursor solutions with different Yb/Er dopant ratios. The particles were additionally thermally treated at 1100 °C for 12, 24 and 48 h. The structural and morphological characteristics of particles were studied by X-ray powder diffraction, Fourier transform infrared spectroscopy, field-emission scanning electron microscopy, energy dispersive X-ray analysis and specific surface area (BET) and were further correlated with their advanced optical properties. For the recorded up-conversion emissions, originating from the following Er3+ transitions: [2H9/2→4I15/2] in blue (407–420 nm); [2H11/2, 4S3/2→4I15/2] green: 510–590 nm; and [4F9/2→4I15/2] in red (640–720 nm) spectral region, the corresponding lifetimes were acquired in the wide temperature range (10–300 K). The most intense green up-conversion emission with the long decay of 550 ms is recorded for Y1.97Yb0.02Er0.01O3 particles thermally treated at 1100 °C for 24 h. 相似文献
117.
Adrián E. Yuchechen S. Gabriela Lakkis Pablo O. Canziani 《International journal of remote sensing》2017,38(12):3483-3501
Annual anomalies of Lambertian equivalent reflectivity (LER) retrieved from the total ozone mapping spectrometer spanning the period November 1978–November 2005 were studied in the Southern Hemisphere, in a region bounded by 0° S and 60° S, and their trends were estimated. With the exception of few regions where the variable may represent the contribution of both cloudiness and snow, trends in LER anomalies provided an evolution of total cloudiness. On average, the study region experienced a net increase in LER values of 0.78 reflectivity units (RU) decade?1; if only significant trend values are considered this figure increased to 1.18 RU decade?1. The region that showed the largest upward trend, up to 4 RU decade?1, was located over the eastern Pacific, off the coasts of Chile and Peru, where the presence of marine stratocumulus is frequent. Despite the overall positive trend there were regions that yielded a negative one, most notably the tropical latitudes of South America and Africa. The yearly zonal means also showed a positive trend at all latitudes, but significance occurred beyond 20° S only. Correlation maps between LER anomalies and five different circulation indices were also introduced. The indices with the highest and lowest number of significant correlation values were the Madden–Julian oscillation at 70° E and the quasi-biennial Oscillation, respectively. 相似文献
118.
We examined the individual and combined effects of contrast, sharpness, and grain degradations on the aesthetic judgments of photographs depicting natural and human-made scenes. Our systematic approach demonstrated that certain degradations, and their combinations, had more impact on aesthetic judgments than others, and that the effects varied depending on the type of scene. We also showed that the degradations were additive in that the more degradations to which an image was subjected, the less it was liked. Finally, we found evidence for a contrast effect in which the aesthetic judgments of high-quality images were more positive as the images they were presented with were more degraded. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
119.
Carlos L. De Pablo María J. Roldán-Martín Pilar Martín De Agar 《Landscape Research》2013,38(5):571-589
Landscape is organised in mosaics: sets of patches with a defined pattern of boundaries through which patches interact. Changes in patches cause changes in mosaics. Landscape change has two components: a quantitative one, referring to the areas in which changes happen, and a qualitative one, referring to the degree of similarity among the mosaics substituting each other. The quantitative component informs on the magnitude of the change: the total area in which landscape mosaics have changed; the qualitative one informs on the significance thereof: the ecological differences between the mosaics substituting each other. This paper presents an index for quantifying landscape change and for discriminating between magnitude and significance therein. It was tested by study of changes in the landscape mosaics in Madrid, Spain. Results show that the index developed is useful for this purpose. This enables objective comparison of different landscape changes presenting different combinations of magnitude and significance. 相似文献
120.
Pablo Jensen 《The Annals of Regional Science》2011,47(1):81-110
Measuring the spatial distribution of locations of many entities (trees, atoms, economic activities, etc.), and, more precisely,
the deviations from purely random configurations, is a powerful method to unravel their underlying interactions. Several coefficients
have been developed in the past to quantify the possible deviations. It is important to quantify the variances of the coefficients
for random distributions, to ascertain the statistical significance of an empirical deviation. By lack of a proper analytical
expression, the significance is usually obtained by simulating many random configurations by Monte Carlo simulations. In the
present paper, we present an exact analytical expression for the variance of several spatial coefficients for random distributions, and we rigorously show that these distributions asymptotically follow a Normal law. These two results eliminate the need for cumbersome Monte
Carlo simulations. They also allow to understand qualitatively the main factors that may change the variance: number of sites,
spatial inhomogeneity, etc. 相似文献