6,115 research outputs found
EFFICACY OF SODIUM HYALURONATE AND SYNTHETIC AMINOACIDS IN POSTEXTRACTIVE SOCKET IN PATIENTS WITH LIVER FAILURE: SPLIT MOUTH STUDY
Tierras elegibles para cultivos forestales según el protocolo de Kyoto en dos partidos de la provincia de Buenos Aires, Argentina
This article reports the amount of land available that can be used only for forestry projects under the KyotoProtocol (KP), Daireaux and Guaminí districts, Buenos Aires Province, Argentina. The information is valuableto potential investors or public or private operators interested in promoting the development of forestry projectsin the Clean Development Mechanism (CDM) PK. We used Landsat 1988, 1989, 2008 and CBERS-2B 2009,the database and images of national forest inventory, surveys of field tree plantations. We compared the coverageof land use on images of 1989 and 2008. Surfaces covered with forests were characterized as non-eligible areas. The remaining area was classified as eligible land. Eligible lands are divided into two subclasses: 1)Eligible land without restriction by the presence of soils Udipsament típico y Hapludol éntico, where growth forest are promising and are areas that do not compete with agricultural use, and 2) Eligible land with forest use restrictions as a result of competition by other land uses or edaphic restrictions. The results indicate that Daireaux and Guaminí Districts have an elegible of 47,021 ha. The eligible areas with restrictions are 314.737ha in Daireaux and 424.456 ha in Guaminí. The non-eligible area is 8.573 ha
Fluid geochemistry of the Los Humeros geothermal field (LHGF - Puebla, Mexico): New constraints for the conceptual model
Geothermal power in Mexico is mainly produced in four geothermal fields operated by the Comision Federal de Electricidad (CFE): Cerro Prieto, Los Azufres, Los Humeros, and Las Tres Virgenes. The Los Humeros Geothermal Field (LHGF) is ranked third in terms of generated capacity, and in the last decade its installed capacity has doubled (up to 95.0 MW). Further increases in the geothermal power generation capacity in Mexico are planned, and thus the LHGF warrants further examination. The development and growth phases of any geothermal project must start from an awareness of the conceptual model of the natural system studied. The recharge mechanism, feeding zones, and fluid flow-path must be identified, along with the estimation of the temperature at the productive level and of phase separation (liquid - steam). To accomplish this, detailed fluid geochemical surveys were carried out in June 2017 and March 2018, in which 57 and 87 samples were collected, respectively, from cold and thermal springs, water wells and maar lakes located around and inside the LHGF. Samples from fumaroles inside the producing area were also collected for the first time, together with fluid from re-injection wells. The presence of a meteoric component, which plays an important role at the regional scale, is confirmed by the chemical and isotope data, and its contribution in terms of recharge may be higher than previously assumed. The Sierra Madre Oriental, on the west side of the LHGF, is characterized by widespread outcrops of limestone belonging to the same geological formation as those at the bottom of the LHGF. The isotope composition (delta D and delta O-18, respectively -77.3 parts per thousand and -10.50 parts per thousand for the hypothetical Infiltration Water IW) is similar to that observed in cold springs located in the Sierra Madre Oriental, and from this the evolution of isotopes in the liquid-rock-steam system during water-rock interaction and phase separation processes can be modelled. Thus, the experimental data obtained for natural gas emissions (fumarolic condensates) and for geothermal fluids can be reproduced. These findings suggest that geothermal fluids in the LHGF are likely to be derived from meteoric water infiltrating (IW) the limestone outcrops of the Sierra Madre Oriental. During their flow-path, the infiltrating waters exchange isotopes at a high temperature with the crustal rocks, which have a much higher O-18/O-16 ratio, resulting in a shift towards higher delta O-18 (-4.35 parts per thousand +/- 1) as the water O exchanges with rock O. The vapor phase can be separated from this deep water (DW) and it is discharged from the fumarolic effluents of Loma Blanca. Single Step Vapor Separation (SSVS) and Continuous Steam Separation processes (CSS) were modelled using stable isotopes of water. The results of geochemical modeling agree with available data for geothermal liquids discharged from several geothermal wells, suggesting that steam separation may be interpreted either as SSVS or CSS. Other processes can affect the chemistry and isotope composition of geothermal fluids (e.g. phase segregation, gas exchange, contributions from magmatic-volcanic deep fluids and re-injection fluids). The proposed conceptual model is consistent with both the geochemical data and the geological setting, and provides a useful point of reference for examining the fluid flow-path and geochemical processes active in the LHGF, at least at a general level. An involvement of magmatic-volcanic deep fluids in the feeding mechanism of the geothermal system cannot be excluded at priori, but the regional meteoric end-member is supported by the data and it seems the most important component
Assessment, control, and prevention of microbiological and chemical hazards in seasonal swimming pools of the Versilia district (Tuscany, central Italy).
Abstract
Although in Europe the quality of swimming pools (SPs) is dictated by regulations, microbiological and chemical hazards are described in the literature. Environmental bacteria or toxic disinfection by-product (DBP) compounds may indeed be recovered in waters even after disinfection. We evaluated the water quality from 26 outdoor seasonal SPs of the Versilia district, according to requirements of Regional Decree 54R/2015. In spring 2017, supply and reinstatement waters were collected after shock hyperchlorination (10 mg/L) while in summertime, a second sampling of waters before entering the pools, as well as in the pools, was performed after SPs were open to the public. In all samples, microbiological and chemical parameters were determined as defined by Directive 98/83/EC and the Italian Health Ministry. Microbiological data were within suggested limits. The first chemical analyses showed that in 35% of the feeding-pool seawater samples, the halogenated organic compounds were higher than the maximum permissible concentrations (30 μg/L). Pool waters were then dechlorinated and re-treated with hydrogen peroxide (10 mg/L) to ensure the abatement of DBPs (from 164 ± 107 to 0.9 ± 0.8 μg/L; p = 0.002). Results highlighted the need of self-controlled procedures for the SPs waters to prevent waterborne diseases and suggested hydrogen peroxide as the most appropriate disinfection method
Assessment of Chemical Compounds for in vitro and in vivo Activity against Bacterial Black Spot of Mango
Bacterial black spot of mango caused by Xanthomonas campestris pv. mangiferaeindicae (Xcm) produces considerable economic losses in many parts in india. The extent to which bactericides control this disease effectively is low. In this study the bactericidal effect of different products was assessed in vitro and in vivo in mango plants under greenhouse conditions. Thirteen antibacterial substances, one commercial formulate and also combinations were tested. In vitro analysis showed that minimal inhibitory concentration (MIC) of antibacterial substances was between 2–8 µgml-1, except for copper sulphate with a MIC value of 100 µgml-1and Vancomycin, Amoxycillin which was not active at 1000 µgml-1. MIC values of commercial formulate bactrinashak ranged between 5 and 30 µgml-1, and combinations of ciprofloxacin + copper sulphate; ciprofloxacin + bactrinashak; ciprofloxacin + copper oxychloride, ciprofloxacin + tetracycline and tetracycline + bactrinashak, showed a great effect at sub-inhibitory concentrations. Treatments including copper sulphate and copper oxychloride significantly reduced disease symptoms on plants, whereas bacitracin was less effective, where as fluconozole and penicillin does not show any inhibition. In two different field trials, the percentage of leaves symptoms was lower, after treatment with copper sulphate combinations than in inoculated controls. These combinations of different antibacterial substances results were better than copper sulphate alone. We conclude that the combination of copper sulphate with ciproflaxacin may be useful in controlling symptoms of this disease in greenhouses
From Exploratory Tunnel to Base Tunnel: Hard Rock TBM Performance Prediction by Means of a Stochastic Approach
AbstractTunnel boring machine (TBM) performance prediction is often a critical issue in the early stage of a tunnelling project, mainly due to the unpredictable nature of some important factors affecting the machine performance. In this regard, deterministic approaches are normally employed, providing results in terms of average values expected for the TBM performance. Stochastic approaches would offer improvement over deterministic methods, taking into account the parameter variability; however, their use is limited, since the level of information required is often not available. In this study, the data provided by the excavation of the Maddalena exploratory tunnel were used to predict the net and overall TBM performance for a 2.96 km section of the Mont Cenis base tunnel by using a stochastic approach. The preliminary design of the TBM cutterhead was carried out. A prediction model based on field penetration index, machine operating level and utilization factor was adopted. The variability of the parameters involved was analysed. A procedure to take into account the correlation between the input variables was described. The probability of occurrence of the outcomes was evaluated, and the total excavation time expected for the tunnel section analysed was calculated
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