The effect of the ocean water immersion and UV ageing on the dynamic mechanical properties of the PPS/glass fiber composites

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effect of plant density on Stevia rebaudiana Bertoni water consumption

Stevia rebaudiana is a traditional crop of Latin America, now rising to international interest thanks to its specific glycosides that are very sweet and still poor of calories making its potential interesting for dietary recommendations. Its short growing cycle makes this species possible as an annual crop also in non tropical areas, including the Mediterranean Basin and parts of Italy, where rainfall or irrigation is available during late spring and summer. One of the main concerns is the quantity of water necessary for the crop and the ideal number of plants per hectare in order to maximize water use efficiency. The present research was carried out in central Italy to compare yields and water consumption in plots with three plant densities (50, 25, 16 plants per square metre). The results show that the most dense plots can give the best results in the area of the trial.

Regulation of the private provision of public water-related services

Includes bibliography

An assessment of the economic impact of climate change on the water sector in Saint Vincent and The Grenadines

Water security which is essential to life and livelihood, health and sanitation, is determined not only by the water resource, but also by the quality of water, the ability to store surplus from precipitation and runoff, as well as access to and affordability of supply. All of these measures have financial implications for national budgets. The water sector in the context of the assessment and discussion on the impact of climate change in this paper includes consideration of the existing as well as the projected available water resource and the demand in terms of: quantity and quality of surface and ground water, water supply infrastructure - collection, storage, treatment, distribution, and potential for adaptation. Wastewater management infrastructure is also considered a component of the water sector. Saint Vincent and the Grenadines has two distinct hydrological regimes: mainland St Vincent is one of the wetter islands of the eastern Caribbean whereas the Grenadines have a drier climate than St Vincent. Surface water is the primary source of water supply on St Vincent, whereas the Grenadines depend on man-made catchments, rainwater harvesting, wells, and desalination. The island state is considered already water stressed as marked seasonality in rainfall, inadequate supply infrastructure, and institutional capacity constrains water supply. Economic modelling approaches were implemented to estimate sectoral demand and supply between 2011 and 2050. Residential, tourism and domestic demand were analysed for the A2, B2 and BAU scenarios. In each of the three scenarios – A2, B2 and BAU Saint Vincent and the Grenadines will have a water gap represented by the difference between the two curves during the forecast period of 2011 and 2050. The amount of water required increases steadily between 2011 and 2050 implying an increasing demand on the country‘s resources as reflected by the fact that the water supply that is available cannot respond adequately to the demand. The Global Water Partnership in its 2005 policy brief suggested that the best way for countries to build the capacity to adapt to climate change will be to improve their ability to cope with today‘s climate variability (GWP, 2005). This suggestion is most applicable for St Vincent and the Grenadines, as the variability being experienced has already placed the island nation under water stress. Strategic priorities should therefore be adopted to increase water production, increase efficiency, strengthen the institutional framework, and decrease wastage. Cost benefit analysis was stymied by data availability, but the ―no-regrets approach‖ which intimates that adaptation measures will be beneficial to the land, people and economy of Saint Vincent and the Grenadines with or without climate change should be adopted.

Simulations of Ground-Water Flow, Transport, Age, and Particle Tracking near York, Nebraska, for a Study of Transport of Anthropogenic and Natural Contaminants (TANC) to Public-Supply Wells

The U.S. Geological Survey (USGS) is committed to providing the Nation with credible scientific information that helps to enhance and protect the overall quality of life and that facilitates effective management of water, biological, energy, and mineral resources (http://www.usgs.gov/). Information on the Nation’s water resources is critical to ensuring long-term availability of water that is safe for drinking and recreation and is suitable for industry, irrigation, and fish and wildlife. Population growth and increasing demands for water make the availability of that water, now measured in terms of quantity and quality, even more essential to the long-term sustainability of our communities and ecosystems. The USGS implemented the National Water-Quality Assessment (NAWQA) Program in 1991 to support national, regional, State, and local information needs and decisions related to water-quality management and policy (http://water.usgs.gov/nawqa). The NAWQA Program is designed to answer: What is the condition of our Nation’s streams and ground water? How are conditions changing over time? How do natural features and human activities affect the quality of streams and ground water, and where are those effects most pronounced? By combining information on water chemistry, physical characteristics, stream habitat, and aquatic life, the NAWQA Program aims to provide science-based insights for current and emerging water issues and priorities. From 1991-2001, the NAWQA Program completed interdisciplinary assessments and established a baseline understanding of water-quality conditions in 51 of the Nation’s river basins and aquifers, referred to as Study Units (http://water.usgs.gov/nawqa/studyu.html).

Water sorption of CH3- and CF3-Bis-GMA based resins with additives

Objectives: To evaluate the effect of additives on the water sorption characteristics of Bis-GMA based copolymers and composites containing TEGDMA, CH(3)Bis-GMA or CF(3)Bis-GMA. Material and methods: Fifteen experimental copolymers and corresponding composites were prepared combining Bis-GMA and TEGDMA, CH(3)Bis-GMA or CF(3)Bis-GMA, with aldehyde or diketone (24 and 32 mol%) totaling 30 groups. For composites, barium aluminosilicate glass and pyrogenic silica was added to comonomer mixtures. Photopolymerization was effected by 0.2 wt% each of camphorquinone and N,N-dimethyl-p-toluidine. Specimen densities in dry and water saturated conditions were obtained by Archimedes' method. Water sorption and desorption were evaluated in a desorption-sorption-desorption cycle. Water uptake (%WU), water desorption (%WD), equilibrium solubility (ES; mu g/mm(3)), swelling (f) and volume increase (%V) were calculated using appropriate equations. Results: All resins with additives had increased %WU and ES. TEGDMA-containing systems presented higher %WU, %WD, ES, f and %V values, followed by resins based on CH(3)Bis-GMA and CF(3)Bis-GMA. Conclusions: Aldehyde and diketone led to increases in the water sorption characteristics of experimental resins.

Effects of trophic levels (chlorophyll and phosphorous content) in three different water bodies (urban lake, reservoir and aquaculture facility) on gill morphology of Nile tilapia (Oreochromis niloticus)

Histological and ultrastructural analyses of gills were observed in Nile tilapia collected from three different waterbodies in southeast Brazil: an urban lake in a park in the city of São Paulo, a reservoir in a rural city, and a commercial aquaculture facility. These aterbodies were analyzed and classified as hypereutrophic, eutrophic, and supereutrophic, respectively, with 310.00, 94.00, 28.00 of phosphate (PO2_ 4 lg L _1) and 65.49, 24.95, 12.83 of chlorophyll (lg L _1). A significant difference in the histological alterations index (HAI) was observed only in fish from the urban lake, with the presence of cell hypertrophy, hyperplasia, aneurism, and other alterations. When compared to the other groups, a large quantity of rodlet cells was also observed in the urban group. These results demonstrate the correlation of eutrophic states of water with gill morphology. Also discussed is the premise that large amounts of organic material dissolved in water can alter the morphology of the fish gills

Vegetation and hydrologic influences on carbon and nitrogen in subsurface water of a forested riparian wetland

Vegetation communities affect carbon and nitrogen dynamics in the subsurface water of mineral wetlands through the quality of their litter, their uptake of nutrients, root exudation and their effects on redox potential. However, vegetation influence on subsurface nutrient dynamics is often overshadowed by the influences of hydrology, soils and geology on nutrient dynamics. The effects of vegetation communities on carbon and nitrogen dynamics are important to consider when managing land that may change vegetation type or quantity so that wetland ecosystem functions can be retained. This study was established to determine the magnitude of the influences and interaction of vegetation cover and hydrology, in the form of water table fluctuations, on carbon and nitrogen dynamics in a northern forested riparian wetland. Dissolved organic carbon (DOC), dissolved inorganic carbon (DIC), nitrate (NO3-) and ammonium (NH4+) concentrations were collected from a piezometer network in four different vegetation communities and were found to show complex responses to vegetation cover and water table fluctuations. Dissolved organic carbon, DIC, NO3- and NH4+ concentrations were influenced by forest vegetation cover. Both NO3- and NH4+ were also influenced by water table fluctuations. However, for DOC and NH4+ concentrations there appeared to be more complex interactions than were measured by this study. The results of canonical correspondence analysis (CCA) and analysis of variance (ANOVA) did not correspond in relationship to the significance of vegetation communities. Dissolved inorganic carbon was influenced by an interaction between vegetation cover and water table fluctuations. More hydrological information is needed to make stronger conclusions about the relationship between vegetation and hydrology in controlling carbon and nitrogen dynamics in a forested riparian wetland.

Small quantity but large effect — How minor phases control strain localization in upper mantle shear zones

Low viscosity domains such as localized shear zones exert an important control on the geodynamics of the uppermost mantle. Grain size reduction and subsequent strain localization related to a switch from dislocation to diffusion creep is one mechanism to form low viscosity domains. To sustain strain localization, the grain size of mantle minerals needs to be kept small over geological timescales. One way to keep olivine grain sizes small is by pinning of mobile grain boundaries during grain growth by other minerals (second phases). Detailed microstructural studies based on natural samples from three shear zones formed at different geodynamic settings, allowed the derivation of the olivine grain-size dependence on the second-phase content. The polymineralic olivine grain-size evolution with increasing strain is similar in the three shear zones. If the second phases are to pin the mobile olivine grain boundary the phases need to be well mixed before grain growth. We suggest that melt-rock and metamorphic reactions are crucial for the initial phase mixing in mantle rocks. With ongoing deformation and increasing strain, grain boundary sliding combined with mass transfer processes and nucleation of grains promotes phase mixing resulting in fine-grained polymineralic mixtures that deform by diffusion creep. Strain localization due to the presence of volumetrically minor minerals in polymineralic mantle rocks is only important at high strain deformation (ultramylonites) at low temperatures (<~800°C). At smaller strain and stress conditions and/or higher temperatures other parameters like overall energy available to deform a given rock volume, the inheritance of mechanical anisotropies or the presence of water or melts needs to be considered to explain strain localization in the upper mantle.

The amount of water loss was determined by drying at 110°C

Deep-sea deposits, which resemble in nearly every respect the deep-sea oozes have been observed in many islands of the East-Indian Archipelago, notably the islands of Borneo, Rotti and Timor. Manganese nodules are found in equivalents of deeep-sea red clays on Timor and Rotti island. In this paper, those relative to red clay deposits dating from a Cretaceous ocean are analysed in detail in the vicinity of the town of Niki Niki in Western Timor.

Geochemistry on interstitial water of 5 sediment profiles from the Persian Gulf

The landward part of the 7 km wide sabkha at Umm Said, SE Qatar, is filled with a stagnant brine virtually saturated with halite. Recent dolomite occurs in the sabkha sediments, the quantity being fully accounted for by the amount of Mg++ ions lost from the interstitial brine. The existence of a reflux system in the seaward parts of the sabkha was established. It was not, however, possible to gi ve any unequivocal demonstration of the effect of this potential system for dolomitization . Although both a reflux mechanism and Recent dolomite formation occur in this tidal flat, the first process has apparently not influenced the second sufficiently to permit the demonstration of reflux dolomitization.

Full scale test for explosion water barriers in small cross-section galleries

Underground coal mines explosions generally arise from the inflammation of a methane/air mixture. This explosion can also generate a subsequent coal dust explosion. Traditionally such explosions have being fought eliminating one or several of the factors needed by the explosion to take place. Although several preventive measures are taken to prevent explosions, other measures should be considered to reduce the effects or even to extinguish the flame front. Unlike other protection methods that remove one or two of the explosion triangle elements, namely; the ignition source, the oxidizing agent and the fuel, explosion barriers removes all of them: reduces the quantity of coal in suspension, cools the flame front and the steam generated by vaporization removes the oxygen present in the flame. Passive water barriers are autonomous protection systems against explosions that reduce to a satisfactory safety level the effects of methane and/or flammable dust explosions. The barriers are activated by the pressure wave provoked in the explosion destroying the barrier troughs and producing a uniform dispersion of the extinguishing agent throughout the gallery section in quantity enough to extinguish the explosion flame. Full scale tests have been carried out in Polish Barbara experimental mine at GIG Central Mining Institute in order to determine the requirements and the optimal installation conditions of these devices for small sections galleries which are very frequent in the Spanish coal mines. Full scale tests results have been analyzed to understand the explosion timing and development, in order to assess on the use of water barriers in the typical small crosssection Spanish galleries. Several arrangements of water barriers have been designed and tested to verify the effectiveness of the explosion suppression in each case. The results obtained demonstrate the efficiency of the water barriers in stopping the flame front even with smaller amounts of water than those established by the European standard. According to the tests realized, water barriers activation times are between 0.52 s and 0.78 s and the flame propagation speed are between 75 m/s and 80 m/s. The maximum pressures (Pmax) obtained in the full scale tests have varied between 0.2 bar and 1.8 bar. Passive barriers protect effectively against the spread of the flame but cannot be used as a safeguard of the gallery between the ignition source and the first row of water troughs or bags, or even after them, as the pressure could remain high after them even if the flame front has been extinguished.

River Restoration in Spain: Theoretical and Practical Approach in the Context of the European Water Framework Directive.

River restoration is becoming a priority in many countries because of increasing the awareness of environmental degradation. In Europe, the EU Water Framework Directive (WFD) has significantly reinforced river restoration, encouraging the improvement of ecological status for water bodies. To fulfill the WFD requirements, the Spanish Ministry of the Environment developed in 2006 a National Strategy for River Restoration whose design and implementation are described in this paper. At the same time many restoration projects have been conducted, and sixty of them have been evaluated in terms of stated objectives and pressures and implemented restoration measures. Riparian vegetation enhancement, weir removal and fish passes were the most frequently implemented restoration measures, although the greatest pressures came from hydrologic alteration caused by flow regulation for irrigation purposes. Water deficits in quantity and quality associated with uncontrolled water demands seriously affect Mediterranean rivers and represent the main constraint to achieving good ecological status of Spanish rivers, most of them intensively regulated. Proper environmental allocation of in-stream flows would need deep restrictions in agricultural water use which seem to be of very difficult social acceptance. This situation highlights the need to integrate land-use and rural development policies with water resources and river management, and identifies additional difficulties in achieving the WFD objectives and good ecological status of rivers in Mediterranean countries.

Large vortex-like structure of dipole field in computer models of liquid water and dipole-bridge between biomolecules

We propose a framework to describe the cooperative orientational motions of water molecules in liquid water and around solute molecules in water solutions. From molecular dynamics (MD) simulation a new quantity “site-dipole field” is defined as the averaged orientation of water molecules that pass through each spatial position. In the site-dipole field of bulk water we found large vortex-like structures of more than 10 Å in size. Such coherent patterns persist more than 300 ps although the orientational memory of individual molecules is quickly lost. A 1-ns MD simulation of systems consisting of two amino acids shows that the fluctuations of site-dipole field of solvent are pinned around the amino acids, resulting in a stable dipole-bridge between side-chains of amino acids. The dipole-bridge is significantly formed even for the side-chain separation of 14 Å, which corresponds to five layers of water. The way that dipole-bridge forms sensitively depends on the side-chain orientations and thereby explains the specificity in the solvent-mediated interactions between biomolecules.

Integrated Water Resources Management: Principles for Coordination in the Coal River Watershed, West Virginia

Mountaintop removal (MTR) coal mining has had a significant influence on the water sources within the Coal River watershed of West Virginia. Using an approach such as Integrated Water Resources Management (IWRM) may improve management for the long-term protection and sustainability of the Coal River watershed‰Ûªs water resources. This Capstone project analyzes current site-specific information related to water quality and quantity and the impacts of MTR in the region, reviews current management challenges, and identifies key stakeholders to be included in IWRM planning. This information provided a foundation for the development of a preliminary IWRM coordination plan for the Coal River watershed based on IWRM principles and guidelines. It is hoped that this preliminary plan will contribute to the development of a final coordinated IWRM plan.