Samarium-Substitution Effects in Sol-Gel Derived Yttrium Aluminium Garnet

In this study, yttrium aluminium garnet (YAG) powders substituted by samarium were prepared by simple an aqueous sol-gel method using aluminium nitrate nonahydrate, yttrium oxide, samarium oxide as the starting materials and etane-1,2-diol as complexing agent. The powders annealed at 1000 degrees Celsius in air were characterized by X-ray diffraction (XRD) analysis, infrared spectroscopy (IR) and scanning electron microscopy (SEM). It was demonstrated, however, that the total substitution of yttrium by samarium does not proceed in the YAG. Pure cubic garnet phase was formed only at low concentration of samarium. With further substitution, the main part of garnet phase transformed in to the perovskite samarium aluminate phase. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3483

Ecosystem Services in Decision Making: Time to Deliver

Over the past decade, efforts to value and protect ecosystem services have been promoted by many as the last, best hope for making conservation mainstream – attractive and commonplace worldwide. In theory, if we can help individuals and institutions to recognize the value of nature, then this should greatly increase investments in conservation, while at the same time fostering human well-being. In practice, however, we have not yet developed the scientific basis, nor the policy and finance mechanisms, for incorporating natural capital into resource- and land-use decisions on a large scale. Here, we propose a conceptual framework and sketch out a strategic plan for delivering on the promise of ecosystem services, drawing on emerging examples from Hawai‘i. We describe key advances in the science and practice of accounting for natural capital in the decisions of individuals, communities, corporations, and governments

Ecosystem Services in Decision Making: Time to Deliver

Over the past decade, efforts to value and protect ecosystem services have been promoted by many as the last, best hope for making conservation mainstream – attractive and commonplace worldwide. In theory, if we can help individuals and institutions to recognize the value of nature, then this should greatly increase investments in conservation, while at the same time fostering human well-being. In practice, however, we have not yet developed the scientific basis, nor the policy and finance mechanisms, for incorporating natural capital into resource- and land-use decisions on a large scale. Here, we propose a conceptual framework and sketch out a strategic plan for delivering on the promise of ecosystem services, drawing on emerging examples from Hawai‘i. We describe key advances in the science and practice of accounting for natural capital in the decisions of individuals, communities, corporations, and governments

Sol-Gel Synthesis and Characterization of Cerium Substituted Calcium Hydroxyapatite

In this study, an aqueous sol-gel chemistry route based on phosphoric acid as the phosphorus precursor, calcium acetate monohydrate and cerium (III) nitrate hexahydrate as source of calcium and cerium ions, respectively, have been used to prepare cerium-substituted calcium hydroxyapatite (CHAp) powders. The tartaric acid was used as complexing agent in the sol-gel processing. The final products were obtained by calcination of the dry precursor gels for 5 h at 1000 °C. The phase transformations, composition, and structural changes in the polycrystalline samples were studied by infrared spectroscopy (IR), X-ray powder diffraction analysis (XRD), scanning electron microscopy (SEM), UV-visible reflection spectroscopy and luminescence measurements. It was demonstrated, however, that the high substitution of calcium by cerium does not proceed in the CHAp. The reflectance spectra of Ce substituted CHAp show nearly 100% reflection in the wavelength range of 450-800 nm. The luminescent properties of these samples were also investigated. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3493

Europium substitution effects in superconducting YBa2Cu4O8 synthesized under one atmosphere oxygen pressure

Y1−xEuxBa2Cu4O8 powder samples, with x=0, 0.25, 0.5, 0.75, and 1.0, were synthesized at ambient pressure using either an acetate-tartrate sol-gel method or a LiF flux process. The lattice parameters and purity of the samples were checked using X-ray diffraction. The superconducting transition was monitored by magnetic-susceptibility measurements. Replacing yttrium with europium increased the unit-cell volume, decreased the orthorhombicity (b/a) and the critical temperature. The hyperfine interactions at the europium site were studied by Eu151 Mössbauer spectroscopy. The complete quadrupole Hamiltonian of the 21.5-keV γ transition of Eu151 was successfully applied in the analyses of the Mössbauer spectra. The Mössbauer parameters obtained were found to resemble those measured for the EuBa2Cu3Cu3O7−δ (1:2:3) system. It was demonstrated that magnetic alignment of the crystallites could not be obtained with an 11.7-T field, contrary to the 1:2:3 and other high-Tc systems. The magnetic susceptibility for 1:2:4 single crystals appears to be isotropic.Peer reviewe

Synthesis and Investigation of Modified Silica Coatings for Biotechnology

Mesoporous organic-inorganic hybrid composites on glass substrates were prepared by the sol-gel method for testing the proteins adhesion. Different types of hydrophobic/hydrophilic silica sol-gels were prepared using tetraethoxysilane (TEOS) as starting material and modified with hexamethyldisilazane (HMDS). Sol-gel thin films were successfully prepared with the dip-coating technique on glass surfaces. The coatings surface characteristics were evaluated. The prepared sol-gel derived colloidal silica coatings and modified coatings were characterized by wettability measurements. Also, infrared spectroscopy, atomic force microscope (AFM) assay were used to characterise the surfaces. The coatings of colloidal silica (VT104, water contact angle 17°), polysiloxane sol (VT111, 64°) methyl-modified sols (VT079, 144° and VT112, 47°) with various wettability properties were tested for CaCo-2 cells proliferation. Methylmodified coating VT112 proved to be the best substrate for cell proliferation.Для тестування адгезії білків золь-гель методом приготовано мезопоруваті органо-неорганічні гібридні композити на скляних підкладинках. Різні типи гідрофобних та гідрофільних кремнеземних золів та гелів було приготовано з використанням тетраетоксисилану (ТЕОС) як вихідного матеріалу і модифіковано гексаметилдисилазаном (ГМДС). Тонкі золь-гель плівки було успішно приготовано за допомогою процедури глазурування зануренням на скляних поверхнях. Одержано характеристики поверхонь покриттів. Одержані шляхом золь-гель синтезу покриття – похідні колоїдного кремнезему та модифіковані покриття було охарактеризовано вимірюванням змочуваності. Для характеризації поверхонь було також використано аналіз за допомогою інфрачервоної спектроскопії та атомної силової мікроскопії (АСМ). Покриття з колоїдного кремнезему (VT104, кут змочування водою 17°), полісилоксановий золь (VT111, 64°), метил-модифіковані золі (VT079, 144° та VT112, 47°) з різною змочуваністю було протестовано для розмноження клітин СаСо-2. Метил-модифіковане покриття VT112 виявилось найкращим субстратом для розмноження клітин.Для тестирования адгезии белков золь-гель методом приготовлены мезопористые органо-неорганические гибридные композиты на стеклянных подложках. Разные типы гидрофобных и гидрофильных кремнеземных золей и гелей были приготовлены с использованием тетраэтоксисилана (ТЭОС) как исходного материала и модифицированы гексаметилдисилазаном (ГМДС). Тонкие золь-гель пленки были успешно приготовлены с помощью процедуры глазурирования погружением на стеклянных поверхностях. Получены характеристики поверхностей покрытий. Полученные путем золь-гель синтеза покрытия – производные коллоидного кремнезема и модифицированные покрытия были охарактеризованы измерением смачиваемости. Для характеризации поверхностей был также использован анализ с помощью инфракрасной спектроскопии и атомной силовой микроскопии (АСМ). Покрытия из коллоидного кремнезема (VT104, угол смачивания водой 17°), полисилоксановый золь (VT111, 64°), метил-модифицированные золи (VT079, 144° и VT112, 47°) с разной смачиваемостью были протестированы для размножения клеток СаСо-2. Метилмодифицированное покрытие VT112 оказалось наилучшим субстратом для размножения клеток

Spatial Dynamics and Ecosystem Functioning

Ecosystem functioning is dependent upon the way species become distributed across space

Notes from the field: Lessons learned from using ecosystem service approaches to inform real-world decisions

While there have been rapid advances in assessments of biodiversity and ecosystem services (BES), a critical remaining challenge is how to move from scientific knowledge to real-world decision making. We offer 6 lessons from our experiences applying new approaches and tools for quantifying BES in 20 pilot demonstrations: (1) Applying a BES approach is most effective in leading to policy change as part of an iterative science-policy process; (2) simple ecological production function models have been useful in a diverse set of decision contexts, across a broad range of biophysical, social, and governance systems. Key limitations of simple models arise at very small scales, and in predicting specific future BES values; (3) training local experts in the approaches and tools is important for building local capacity, ownership, trust, and long-term success; (4) decision makers and stakeholders prefer to use a variety of BES value metrics, not only monetary values; (5) an important science gap exists in linking changes in BES to changes in livelihoods, health, cultural values, and other metrics of human wellbeing; and (6) communicating uncertainty in useful and transparent ways remains challenging

Sol-gel derived lanthanide-substituted layered double hydroxides Mg3/Al1-xLnx

Mg/Al/Ln (Ln = Nd, Sm, Eu) layered double hydroxides (LDHs) were synthesized using sol–gel method for the first time to the best our knowledge. The obtained materials were characterized by X-ray di raction analysis and fluorescence spectroscopy. The phase composition and luminescent properties of these LDHs were investigated and discussed. The Ln3+ substitution e ects were investigated in the Mg3Al1−xLnx LDHs by changing the Ln3+ concentration in the metal cation layers up to 10 mol%. It was demonstrated that only Mg3Al1−xEux LDHs showed luminescence properties, however, no any light emission was observed for the Mg3Al1−xNdx and Mg3Al1−xSmx LDH samplespublishe