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Chemical techniques in the service of art. Researchers have analyzed UNED Paleolithic paintings in the caves of Tito Bustillo and El Buxu (Asturias) to determine its composition. The study reveals that its main component is the mineral hematite and the grain of the pigments are so fine as the one used today.
“It is surprising that the grain size of pigment found in some paintings of the cave of Tito Bustillo is similar to that used today,” says Antonio Hernanz, researcher at the Department of Science and Technology, UNED Physicochemical and author of the study.
Science, UNED, University of Castilla la Mancha and University of Alcala de Henares have analyzed the composition of different localized Paleolithic cave paintings in the caves of Tito Bustillo in Asturias and the Buxu.
The main component have found that hematite is the mineral, with three granular size: less than one micron to 10 microns and 30 microns. “They’re very small sizes, and the finer the grain, the greater the power of paint to cover a surface,” says Hernanz.
The study, published in Journal of Raman Spectroscopyreveals that the oldest representations (belonging to the Aurignacian culture, with an estimated age of 30,000 years) have a smaller grain than the rest, less than one micron. This size suggests that “the oldest paintings we have used a technique developed to prepare the pigment,” adds the researcher.
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Researchers at the Universitat Autònoma de Barcelona (UAB) have developed an electronic tongue to identify different types of cava through a combination of sensor systems and advanced mathematical tools for processing. The device enables an automated classification similar to that conduct a sommelier and can be useful for the detection of defects during the production of these wines.
Different types of cava vary in the amount of sugar is added to the expedition liquor after the second fermentation (which gives the carbon dioxide). So it is interesting to know the amount of sugar added, since this will determine the type of champagne produced. To design an electronic tongue to dig, researchers at the Sensors and Biosensors Group at the UAB, led by Professor Manel de Valle, have carried out the identification of various samples of cava on the basis of voltammetric measurements. Through a combination of measurement systems and chemical processing advanced mathematical tools, have managed to mimic the human taste system and carry out a task of distinguishing between different kinds of champagne, obtaining a classification similar to that conduct a sommelier .
Furthermore, using the standard addition method of second order (SOSAM) has been possible to quantify the added sugars in the production process of the cava, which demonstrates the potential of these processing tools. Language can now identify three types of champagne:
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Scientists at the University of Granada (UGR) has created a software application installed in the mobile phone, to analyze the concentration of chemical species by taking a simple photograph to a sensor strip which also designed. The study is published in the latest issue of the journal Sensors and Actuators B (Chemical) .
(The software allows the analysis of chemical species. Image: UGR.)
Researchers in the areas of Analytical Chemistry and Electronics of the UGR have developed a platform that, when installed on a mobile phone, to analyze the concentration of chemical species by performing a simple photograph to a sensor strip. The strip also designed the researchers themselves.
This platform consists of two elements. On the one hand, the team has designed a colorimetric chemical sensor for single use and low cost (in the form of strip), which changes color depending on the concentration of a particular chemical species may be present in liquids or gases.
In parallel, they have created a software application for mobile phones, capable of measuring the color takes on the strip coming into contact with the analyte and, from there, if it contains the substance in question or not and at what concentration, all from a photograph of the test strip made with the mobile phone itself and processed by this application.
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For the first time have been found in interstellar space, molecules of hydrogen peroxide, known as hydrogen peroxide. The discovery, made with the APEX telescope in Chile, provides clues to the chemical bond between two molecules essential for life: water and oxygen.
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The region of Rho Ophiuchi star formation (red circle) which was detected hydrogen peroxide. Image : ESO / S. Guisard.
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Hydrogen peroxide (H 2 O 2 ) plays a key role in water chemistry and ozone in the Earth’s atmosphere and is known for its use as a disinfectant and hair bleach. Now astronomers have detected a region of our galaxy near the star Rho Ophiuchi, about 400 light years away.
An international team of researchers made the discovery with the telescope Atacama Pathfinder Experiment (APEX). This is a collaboration between the Max-Planck Institute for Radio Astronomy (MPIfR), Onsala Space Observatory (OSO) in Sweden and the European Southern Observatory (ESO), which operates one of the highest observation of Earth, at 5,100 meters in Llano de Chajnantor (Chile).
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Polycyclic aromatic hydrocarbons (PAHs) are compounds that can be very organic pollutants. They are, among others, on land occupied by metallurgical and pharmaceutical industries and the fuel-stained waters of ships. Dani Zuazagoitia chemist has proposed simple techniques to analyze the impact of PAHs in various media, based on solid-phase microextraction of the headspace (HS-SPME).
He developed the methodology, prepared for the relevant circumstances and applied it to Gipuzkoa. He defended the thesis at the UPV / EHU, under the title Phase garapena solidoko hidrokarburo mikroerauzketan Aromatik oinarritutako poliziklikoen method determinaziorako. Eta Aplikazioa ingurumen ebaluazioa laginetan (SPMEs Development for the determination of PAHs. Implementation and evaluation in environmental samples).
Zuazagoitia has published several papers with its investigation. The latest is the magazine Soil & Sediment Contamination, entitled Evaluation of soil contamination by polycyclic aromatic hydrocarbons in Guipuzcoa (Northern Spain).
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The biocides are less toxic to the environment if subjected to microencapsulation, because this serves as a shell of the substance. This has been proven chemistry Mariluz Alonso, ina thesis defended at the UPV / EHU.
In this research, has chosen various biocides and other substances complementary in search of a microencapsulated, in addition compatible with the environment, is more soluble in water, more manageable for the operator, with better conservation and effective against flying insects. His thesis is entitled Microencapsulation of biocides and has led to publications in such journals as International Journal of Environmental Analytical Chemistry (the article is entitled Advantages of biocides- β -cyclodextrin inclusion complexes Against active components ).
The aim of the research was to obtain a product that overcomes the limitations of common biocides.These limitations serve a toxicological profile that restricts its use, poor water solubility, high viscosity (in the case of some of them) which complicates handling and high sensitivity (in most cases) to light and temperature. The product not only meets these expectations, but has proven effective against house flies in laboratory tests.
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With the philosophy of doing ‘Green Chemistry’, the research group Coordination and Organometallic Compounds. Applications in Catalytic Processes, University of Huelva has discovered a new route to produce oxazoles, an organic compound that is part of more complex structures of marine origin, some of which have been shown to have fungicidal and antitumor properties, according to scientific studies done previously.
(Detail of machinery for use in catalysis. Image: Sciencepics)
This is an interesting catalytic process or chemical reaction catalyzed “because the oxazoles were obtained from raw materials very affordable or easy to prepare, such as alkynes and azides,” says M. Carmen Nicasio, principal investigator of the research project.
To reduce the time a chemical reaction in the development of new molecules (which is the very purpose of a chemical reaction) catalysts are used, substances or compounds that accelerate the process. This research group specializing in the preparation of metal catalysts (mainly from copper or nickel), just designed a new route for oxazoles from alkynes and azides in a straightforward manner, that is, “without to various chemical processes, “says the researcher.
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The team of researchers at the University Pablo de Olavide (Sevilla) has managed to reel off the molecular structure of asphaltenes, oil-derived aromatic molecules present in the “tar.” The finding will facilitate its dissolution in housekeeping and environmental spills or blockage of the oil transportation pipelines.
(Asphaltene molecule. Image: Sciencepics)
The oil-derived aromatic molecules and present in ‘tar’, asphaltenes are stable in ionic liquids (green solvents), and capable of detecting in those disolventes.Así says a study published in the journal Energy & Fuels ‘.
This procedure opens the door to development of processes of chemical transformation of asphaltenes in these solvents for use as raw materials or disposal in disasters caused by oil spills.
Researchers at the University Pablo de Olavide are proposed to elucidate the molecular basis responsible for molecular recognition. Specifically, the panel is “to understand why a structure is able to recognize a particular molecule, what interactions are involved and if the molecules have to deform a lot when you meet each other and naturally or are prepared to join as a key in a lock, “says Bruno Martinez Hague, director of the study and professor of Chemical and Natural Physical Systems of the University Pablo de Olavide.
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Members of the University of Cádiz (UCA) have developed an innovative process for industrial trickling biofilter inoculation. This method can be applied in water treatment plants and pumping stations and a reduction of operating costs compared with traditional physical-chemical systems.
(The feasibility of this procedure is tested biofilter inoculation. Image: UCA)
Unpleasant odors arising from the treatment plants or pumping stations are usually treated with activated carbon filters or scrubbers using sodium hypochlorite (NaClO) and sodium hydroxide (NaOH), two systems “works quite well but are a high maintenance cost, “said Martin Ramirez, a member of the working group of the UCA.
In the case of coal, “after his exhaustion, he creates a residue that must be taken to the landfill and its withdrawal is a very unhealthy,” says Ramirez, whose group has chosen to use a trickling biofilter. “This is a biological process consisting of a column packed with a synthetic filling polyurethane foam. The contaminated air passes through the upstream fill. In turn, a stream of water falls as rain on the material filling, so that the compounds responsible for odors pass from air to water thus being available for microorganisms, “he explains.
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Allows you to keep the cuprous oxide semiconductor properties in the water, making it suitable for the direct production of hydrogen a cheap and readily available material
A discovery made by researchers at the EPFL will improve the efficiency of photo-electrochemical cells used to produce hydrogen from water. The photo-electrochemical cells convert sunlight into energy used to produce chemical reactions, just like plants do in photosynthesis. The process uses light-sensitive semiconductor materials, such as cuprous oxide, to produce the current needed to power the reactions.
The problem for the use of this oxide in the direct production of hydrogen from water is the fact that its exposure to light in the water makes it unstable, losing the material to its semiconducting properties.
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“It is surprising that the grain size of pigment found in some paintings of the cave of Tito Bustillo is similar to that used today,” says Antonio Hernanz, researcher at the Department of Science and Technology, UNED Physicochemical and author of the study.
Different types of cava vary in the amount of sugar is added to the expedition liquor after the second fermentation (which gives the carbon dioxide). So it is interesting to know the amount of sugar added, since this will determine the type of champagne produced. To design an electronic tongue to dig, researchers at the Sensors and Biosensors Group at the UAB, led by Professor Manel de Valle, have carried out the identification of various samples of cava on the basis of voltammetric measurements. Through a combination of measurement systems and chemical processing advanced mathematical tools, have managed to mimic the human taste system and carry out a task of distinguishing between different kinds of champagne, obtaining a classification similar to that conduct a sommelier .