Forecasting Urban Expansion in the Seven Lakes Area in San Pablo City, Laguna, the Philippines Using the Land Transformation Model

Managing urban growth is essential to the conservation of the Seven Lakes ecosystem in San Pablo City, Laguna province in the Philippines. This study simulates potential conversion of agricultural lands to built-up areas using the land transformation model (LTM), which integrates geographical information systems (GIS) and an artificial neural network (ANN). Historical drivers of the expansion of built-up areas are identified and validated through the application of LTM to land cover maps from 1988 to 2015. Identified drivers include distance to roads, distance to trails, distance to the Seven Lakes, distance to existing built-up areas, slopes and population density per barangay. Results from the percent correct matrix (PCM) were 79.88 per cent for the 1988–2003 runs and 66.42 per cent for the 2003–2015 runs, while the Kappa statistic for both time periods was higher than 0.60, which indicates high levels of agreement. Forecasted scenarios were business-as-usual (BAU) growth, doubled growth and strict law implementation protecting the vicinity around the Seven Lakes and other natural areas. In the BAU scenario, urban expansion spread out along the road networks. The doubled growth scenario showed that further expansion will likely extend around the proximity of the lakes, which may adversely affect the livelihoods of the local fishing communities. As such, it was recommended that preventive measures, such as strict implementation of buffer zones coupled with regular monitoring, be taken to manage land use in the surrounding lake areas

Chiral separation of substituted phenylalanine analogues using chiral palladium phosphine complexes with enantioselective liquid–liquid extraction

Chiral palladium phosphine complexes have been employed in the chiral separation of amino acids and phenylalanine analogues in particular. The use of (S)-xylyl-BINAP as a ligand for the palladium complex in enantioselective liquid–liquid extraction allowed the separation of the phenylalanine analogues with the highest operational selectivity reported to date. 31P NMR, FTIR, FIR, UV-Vis, CD and Raman spectroscopy methods have been applied to gain insight into the binding mechanism of the amino acid substrates with the chiral palladium phosphine complexes. A complexation in a bidentate fashion is proposed.

An analytical study of seismoelectric signals produced by 1-D mesoscopic heterogeneities

The presence of mesoscopic heterogeneities in fluid-saturated porous rocks can produce measurable seismoelectric signals due to wave-induced fluid flow between regions of differing compressibility. The dependence of these signals on the petrophysical and structural characteristics of the probed rock mass remains largely unexplored. In this work, we derive an analytical solution to describe the seismoelectric response of a rock sample, containing a horizontal layer at its center, that is subjected to an oscillatory compressibility test. We then adapt this general solution to compute the seismoelectric signature of a particular case related to a sample that is permeated by a horizontal fracture located at its center. Analyses of the general and particular solutions are performed to study the impact of different petrophysical and structural parameters on the seismoelectric response. We find that the amplitude of the seismoelectric signal is directly proportional to the applied stress, to the Skempton coefficient contrast between the host rock and the layer, and to a weighted average of the effective excess charge of the two materials. Our results also demonstrate that the frequency at which the maximum electrical potential amplitude prevails does not depend on the applied stress or the Skempton coefficient contrast. In presence of strong permeability variations, this frequency is rather controlled by the permeability and thickness of the less permeable material. The results of this study thus indicate that seismoelectric measurements can potentially be used to estimate key mechanical and hydraulic rock properties of mesoscopic heterogeneities, such as compressibility, permeability, and fracture compliance.Comment: 14 pages, 8 figure

Prácticas de laboratorio de fisicoquímica de los materiales. -- 3a. edición, 2007.

89 páginas.Contiene 9 prácticas de laboratorio: 1. Volumen molar parcial. -- 2. Procesos con gas ideal. -- 3. Equilibrio líquido-vapor. -- 4. Equilibrio sólido-líquido. -- 5. Equilibrio químico en reacciones homogéneas. -- 6. Constante de disociación. -- 7. Solubilidad. -- 8. Equilibrio metal-ión metálico. -- 9. Cinética química. Al inicio del texto incluye medidas preventivas y correctivas como normas de seguridad