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A sol-gel method has been developed to prepare pure yttrium aluminum garnet, Y3Al5O12 (YAG), and rare-earth substituted (Ce-Y3Al5O12, Nd-Y3Al5O12, Ho-Y3Al5O12, and Er-Y3Al5O12) samples. The XRD patterns of the polycrystalline powders sintered at 1000ºC showed the formation of monophasic garnet materials. The micro-structural features in the polycristalline samples were studied by scanning electron microscopy. A homogeneous distribution of rare-earth dopants in the YAG lattice was achieved in all of the cases. Electrical conductivity measurements were also performed on the compacts of sol-gel derived Ln-YAG samples. In contrast to the expected dielectric behaviour, the conducting properties of the examined specimens indicate metallic behaviour with the resistivity increasing gradually with increasing temperature.

A sol-gel method has been developed to prepare pure yttrium aluminum garnet Y3Al5O12 (YAG), and rare-earth substituted (Ce-Y3Al5O12, Nd-Y3Al5O12 Ho-Y3Al5O12, and Er-Y3Al5O12) samples. The XRD patterns of the polycrystalline powders sintered at 1000 ºC showed the formation of monophasic garnet materials. The micro-structural features in the polycristalline samples were studied by scanning electron microscopy. A homogeneous distribution of rare-earth do pants in the YAG lattice was achieved in all of the cases. Electrical conductivity measurements were also performed on the compacts of sol-gel derived Ln-YAG samples. In contrast to the expected dielectric behavior, the conducting properties of the examined specimens indicate metallic behavior with the resistivity increasing gradually with increasing temperature.

Šiame straipsnyje rentgeno difrakcinės analizės (XRD) ir Furje transformacijos infraraudonosios spektroskopijos (FTIR) metodais buvo apibūdinti Baltijos gintaro ir arche­ologinės keramikos mėginiai iš dviejų Lietuvos archeolo­ginių radaviečių: Benaičių (Vakarų Lietuva) ir Turlojiškių (Pietų Lietuva). Palyginimui buvo tirti Baltijos pajūrio (ties Nida) ir nežinomos kilmės gintaro, rasto Vilniaus senamies­tyje archeologinių kasinėjimų metu, mėginiai. Tyrimo metu nustatyta, kad keturi gintaro mėginiai iš Baltijos pajūrio, du mėginiai iš archeologinių radaviečių ir nežinomos kilmės gintaro mėginys iš Vilniaus senamiesčio savo chemine sudėtimi niekuo nesiskiria. Todėl daroma išvada, kad visi tirti gintaro mėginiai priskirtini Baltijos jūros regiono gintarams. Archeologinių keramikos mėginių tyrimo pirmiau mi­nėtais metodais metu iš dviejų Lietuvos archeologinių kom­pleksų buvo nustatyta, kad pagal fazinę sudėtį šie mėginiai skiriasi, t. y., be vyraujančios abiejuose mėginiuose kvarco fazės, Turlojiškių mėginiui, kitaip nei Benaičių arheologi­niame komplekse aptiktam ir tirtam mėginiui, būdinga kal­cito kristalinė fazė. Tikėtina, kad keramikos gamyba Turlo­jiškėse vyko žemesnėje temperatūroje, negu Benaičiuose. Daroma išvada, kad tiek XRD, tiek FTIR yra ypač ver­tingi gintaro ir archeologinės keramikos mėginių apibūdini­mo metodai.

On the basis of a two-dimesional model, we estimate diffusion and reaction rates of the yttrium aluminium garnet synthesis at high temperatures.

Urban growth reduces open space in and around cities, impacting biodiversity and ecosystem services. Using land-cover and population data, we examined land consumption and open space loss between 1990 and 2000 for all 274 metropolitan areas in the contiguous United States. Nationally, 1.4 million ha of open space was lost, and the amount lost in a given city was correlated with population growth (r(272) = 0.85, P

Although the message of "global climate change" is catalyzing international action, it is local and regional changes that directly affect people and ecosystems and are of immediate concern to scientists, managers, and policy makers. A major barrier preventing informed climate-change adaptation planning is the difficulty accessing, analyzing, and interpreting climate-change information. To address this problem, we developed a powerful, yet easy to use, web-based tool called Climate Wizard (http://ClimateWizard.org) that provides non-climate specialists with simple analyses and innovative graphical depictions for conveying how climate has and is projected to change within specific geographic areas throughout the world.To demonstrate the Climate Wizard, we explored historic trends and future departures (anomalies) in temperature and precipitation globally, and within specific latitudinal zones and countries. We found the greatest temperature increases during 1951-2002 occurred in northern hemisphere countries (especially during January-April), but the latitude of greatest temperature change varied throughout the year, sinusoidally ranging from approximately 50 degrees N during February-March to 10 degrees N during August-September. Precipitation decreases occurred most commonly in countries between 0-20 degrees N, and increases mostly occurred outside of this latitudinal region. Similarly, a quantile ensemble analysis based on projections from 16 General Circulation Models (GCMs) for 2070-2099 identified the median projected change within countries, which showed both latitudinal and regional patterns in projected temperature and precipitation change.The results of these analyses are consistent with those reported by the Intergovernmental Panel on Climate Change, but at the same time, they provide examples of how Climate Wizard can be used to explore regionally- and temporally-specific analyses of climate change. Moreover, Climate Wizard is not a static product, but rather a data analysis framework designed to be used for climate change impact and adaption planning, which can be expanded to include other information, such as downscaled future projections of hydrology, soil moisture, wildfire, vegetation, marine conditions, disease, and agricultural productivity.

We hypothesized that willingness to financially support conservation depends on one's experience with nature. In order to test this hypothesis, we used a novel time-lagged correlation analysis to look at times series data concerning nature participation, and evaluate its relationship with future conservation support (measured as contributions to conservation NGOs). Our results suggest that the type and timing of nature experience may determine future conservation investment. Time spent hiking or backpacking is correlated with increased conservation contributions 11-12 years later. On the other hand, contributions are negatively correlated with past time spent on activities such as public lands visitation or fishing. Our results suggest that each hiker or backpacker translates to $200-$300 annually in future NGO contributions. We project that the recent decline in popularity of hiking and backpacking will negatively impact conservation NGO contributions from approximately 2010-2011 through at least 2018.

BACKGROUND: The numerous studies examining where efforts to conserve biodiversity should be targeted are not matched by comparable research efforts addressing how conservation investments should be structured and what balance of conservation approaches works best in what contexts. An obvious starting point is to examine the past allocation of effort among conservation approaches and how this has evolved. METHODOLOGY/PRINCIPAL FINDINGS: We examine the past allocation of conservation investment between conservation easements and fee simple acquisitions using the largest land trust in operation, The Nature Conservancy (TNC), as a case study. We analyse the balance of investments across the whole of the US and in individual states when measured in terms of the area protected and upfront cost of protecting land. CONCLUSIONS/SIGNIFICANCE: Across the US as a whole, the proportion of conservation investment allocated to easements is growing exponentially. Already 70% of the area of land protected in a given year, and half of all the financial investment in land conservation, is allocated to easements. The growth rate of conservation easements varies by a factor of two across states when measured in terms of the area protected and by a factor of three in terms of financial expenditure. Yet, we were unable to find consistent predictors that explained this variation. Our results underscore the urgency of implementing best practice guidelines for designing easements and of initiating a wider discussion of what balance of conservation approaches is desirable.

BackgroundConventional wisdom identifies biodiversity hotspots as priorities for conservation investment because they capture dense concentrations of species. However, density of species does not necessarily imply conservation 'efficiency'. Here we explicitly consider conservation efficiency in terms of species protected per dollar invested.Methodology/principal findingsWe apply a dynamic return on investment approach to a global biome and compare it with three alternate priority setting approaches and a random allocation of funding. After twenty years of acquiring habitat, the return on investment approach protects between 32% and 69% more species compared to the other priority setting approaches. To correct for potential inefficiencies of protecting the same species multiple times we account for the complementarity of species, protecting up to three times more distinct vertebrate species than alternate approaches.Conclusions/significanceIncorporating costs in a return on investment framework expands priorities to include areas not traditionally highlighted as priorities based on conventional irreplaceability and vulnerability approaches.

Conservation priority-setting schemes have not yet combined geographic priorities with a framework that can guide the allocation of funds among alternate conservation actions that address specific threats. We develop such a framework, and apply it to 17 of the world's 39 Mediterranean ecoregions. This framework offers an improvement over approaches that only focus on land purchase or species richness and do not account for threats. We discover that one could protect many more plant and vertebrate species by investing in a sequence of conservation actions targeted towards specific threats, such as invasive species control, land acquisition, and off-reserve management, than by relying solely on acquiring land for protected areas. Applying this new framework will ensure investment in actions that provide the most cost-effective outcomes for biodiversity conservation. This will help to minimise the misallocation of scarce conservation resources.

A mathematical model of synthesis of yttrium aluminum garnet is presented and used for computer simulation of the synthesis. The model is based on the reaction-diffusion equations. The model takes into concideration structure of the initial reaction’s components. The digital simulation was carried out using the finite difference technique. Relations between rates of reaction and diffusion was investigated.