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Deep Learning (DL), a groundbreaking branch of Machine Learning (ML), has emerged as a driving force in both theoretical and applied Artificial Intelligence (AI). DL algorithms, rooted in complex and non-linear artificial neural systems, excel at extracting high-level features from data. DL has demonstrated human-level performance in real-world tasks, including clinical diagnostics, and has unlocked solutions to previously intractable problems in virtual agent design, robotics, genomics, neuroimaging, computer vision, and industrial automation. In this paper, the most relevant advances from the last few years in Artificial Intelligence (AI) and several applications to neuroscience, neuroimaging, computer vision, and robotics are presented, reviewed and discussed. In this way, we summarize the state-of-the-art in AI methods, models and applications within a collection of works presented at the 9 International Conference on the Interplay between Natural and Artificial Computation (IWINAC). The works presented in this paper are excellent examples of new scientific discoveries made in laboratories that have successfully transitioned to real-life applications.

Deep Learning (DL), a groundbreaking branch of Machine Learning (ML), has emerged as a driving force in both theoretical and applied Artificial Intelligence (AI). DL algorithms, rooted in complex and non-linear artificial neural systems, excel at extracting high-level features from data. DL has demonstrated human-level performance in real-world tasks, including clinical diagnostics, and has unlocked solutions to previously intractable problems in virtual agent design, robotics, genomics, neuroimaging, computer vision, and industrial automation. In this paper, the most relevant advances from the last few years in Artificial Intelligence (AI) and several applications to neuroscience, neuroimaging, computer vision, and robotics are presented, reviewed and discussed. In this way, we summarize the state-of-the-art in AI methods, models and applications within a collection of works presented at the 9th International Conference on the Interplay between Natural and Artificial Computation (IWINAC). The works presented in this paper are excellent examples of new scientific discoveries made in laboratories that have successfully transitioned to real-life applications.

Deep Learning (DL), a groundbreaking branch of Machine Learning (ML), has emerged as a driving force in both theoretical and applied Artificial Intelligence (AI). DL algorithms, rooted in complex and non-linear artificial neural systems, excel at extracting high-level features from data. DL has demonstrated human-level performance in real-world tasks, including clinical diagnostics, and has unlocked solutions to previously intractable problems in virtual agent design, robotics, genomics, neuroimaging, computer vision, and industrial automation. In this paper, the most relevant advances from the last few years in Artificial Intelligence (AI) and several applications to neuroscience, neuroimaging, computer vision, and robotics are presented, reviewed and discussed. In this way, we summarize the state-of-the-art in AI methods, models and applications within a collection of works presented at the 9th International Conference on the Interplay between Natural and Artificial Computation (IWINAC). The works presented in this paper are excellent examples of new scientific discoveries made in laboratories that have successfully transitioned to real-life applications.

Cobalt-containing lignin-based fibers were synthesized in one step by electrospinning of Alcell lignin solutions as carbon precursor, a low-cost and renewable co-product of the paper making industry. The lignin fibers were thermostabilized in air to avoid the fusion during the carbonization process between 500 and 800 °C to obtain cobalt-containing porous carbon submicron fibers. These carbon fibers catalysts were studied for the Low-Temperature Fischer-Tropsch synthesis. The lignin-derived fibers containing Co catalyst located on the overall carbon fiber surface (internal and external) heat-treated at 500 °C (Co@CF-500) showed the best catalytic performance after 70 h on stream, with 75% and 60% selectivity to C5+ at 220 °C and H2/CO ratios of 1 and 2, respectively, attributed to the high Co dispersion, optimal Co-particle size and better Co accessibility. Higher heat-treatment temperatures leaded to Co-containing carbon fibers with larger metallic cobalt nanoparticles encapsulated in graphitic-type carbon, which rendered them inaccessible for FTS., ChemE/Catalysis Engineering

An energy of 362 MJ is stored in each of the two LHC proton beams for nominal beam parameters. This will be further increased to about 700 MJ in the future high luminosity LHC (HL-LHC) and uncontrolled beam losses represent a significant hazard for the integrity and safe operation of the machine. In this paper, a number of failure mechanisms that can lead to a fast increase of beam losses are analyzed. Most critical are failures in the magnet protection system, namely the quench heaters and a novel protection system called coupling-loss induced quench (CLIQ). An important outcome is that magnet protection has to be evaluated for its impact on the beam and designed accordingly. In particular, CLIQ, which is to protect the new HL-LHC triplet magnets, constitutes the fastest known failure in the LHC if triggered spuriously. A schematic change of CLIQ to mitigate the hazard is presented. A loss of the beam-beam kick due to the extraction of one beam is another source of beam losses with a fast onset. A significantly stronger impact is expected in the upcoming LHC Run III and HL-LHC as compared to the current LHC, mainly due to the increased bunch intensity. Its criticality and mitigation methods are discussed. It is shown that symmetric quenches in the superconducting magnets for the final focusing triplet can have a significant impact on the beam on short timescales. The impact on the beam due to failures of the beam-beam compensating wires as well as coherent excitations by the transverse beam damper are also discussed.

An energy of 362 MJ is stored in each of the two LHC proton beams for nominal beam parameters. This will be further increased to about 700 MJ in the future high luminosity LHC (HL-LHC) and uncontrolled beam losses represent a significant hazard for the integrity and safe operation of the machine. In this paper, a number of failure mechanisms that can lead to a fast increase of beam losses are analyzed. Most critical are failures in the magnet protection system, namely the quench heaters and a novel protection system called coupling-loss induced quench (CLIQ). An important outcome is that magnet protection has to be evaluated for its impact on the beam and designed accordingly. In particular, CLIQ, which is to protect the new HL-LHC triplet magnets, constitutes the fastest known failure in the LHC if triggered spuriously. A schematic change of CLIQ to mitigate the hazard is presented. A loss of the beam-beam kick due to the extraction of one beam is another source of beam losses with a fast onset. A significantly stronger impact is expected in the upcoming LHC Run III and HL-LHC as compared to the current LHC, mainly due to the increased bunch intensity. Its criticality and mitigation methods are discussed. It is shown that symmetric quenches in the superconducting magnets for the final focusing triplet can have a significant impact on the beam on short timescales. The impact on the beam due to failures of the beam-beam compensating wires as well as coherent excitations by the transverse beam damper are also discussed.

An energy of 362 MJ is stored in each of the two LHC proton beams for nominal beam parameters. This will be further increased to about 700 MJ in the future high luminosity LHC (HL-LHC) and uncontrolled beam losses represent a significant hazard for the integrity and safe operation of the machine. In this paper, a number of failure mechanisms that can lead to a fast increase of beam losses are analyzed. Most critical are failures in the magnet protection system, namely the quench heaters and a novel protection system called coupling-loss induced quench (CLIQ). An important outcome is that magnet protection has to be evaluated for its impact on the beam and designed accordingly. In particular, CLIQ, which is to protect the new HL-LHC triplet magnets, constitutes the fastest known failure in the LHC if triggered spuriously. A schematic change of CLIQ to mitigate the hazard is presented. A loss of the beam-beam kick due to the extraction of one beam is another source of beam losses with a fast onset. A significantly stronger impact is expected in the upcoming LHC Run III and HL-LHC as compared to the current LHC, mainly due to the increased bunch intensity. Its criticality and mitigation methods are discussed. It is shown that symmetric quenches in the superconducting magnets for the final focusing triplet can have a significant impact on the beam on short timescales. The impact on the beam due to failures of the beam-beam compensating wires as well as coherent excitations by the transverse beam damper are also discussed.

An energy of 362 MJ is stored in each of the two LHC proton beams for nominal beam parameters. This will be further increased to about 700 MJ in the future high luminosity LHC (HL-LHC) and uncontrolled beam losses represent a significant hazard for the integrity and safe operation of the machine. In this paper, a number of failure mechanisms that can lead to a fast increase of beam losses are analyzed. Most critical are failures in the magnet protection system, namely the quench heaters and a novel protection system called coupling-loss induced quench (CLIQ). An important outcome is that magnet protection has to be evaluated for its impact on the beam and designed accordingly. In particular, CLIQ, which is to protect the new HL-LHC triplet magnets, constitutes the fastest known failure in the LHC if triggered spuriously. A schematic change of CLIQ to mitigate the hazard is presented. A loss of the beam-beam kick due to the extraction of one beam is another source of beam losses with a fast onset. A significantly stronger impact is expected in the upcoming LHC Run III and HL-LHC as compared to the current LHC, mainly due to the increased bunch intensity. Its criticality and mitigation methods are discussed. It is shown that symmetric quenches in the superconducting magnets for the final focusing triplet can have a significant impact on the beam on short timescales. The impact on the beam due to failures of the beam-beam compensating wires as well as coherent excitations by the transverse beam damper are also discussed.

An energy of 362 MJ is stored in each of the two LHC proton beams for nominal beam parameters. This will be further increased to about 700 MJ in the future high luminosity LHC (HL-LHC) and uncontrolled beam losses represent a significant hazard for the integrity and safe operation of the machine. In this paper, a number of failure mechanisms that can lead to a fast increase of beam losses are analyzed. Most critical are failures in the magnet protection system, namely the quench heaters and a novel protection system called coupling-loss induced quench (CLIQ). An important outcome is that magnet protection has to be evaluated for its impact on the beam and designed accordingly. In particular, CLIQ, which is to protect the new HL-LHC triplet magnets, constitutes the fastest known failure in the LHC if triggered spuriously. A schematic change of CLIQ to mitigate the hazard is presented. A loss of the beam-beam kick due to the extraction of one beam is another source of beam losses with a fast onset. A significantly stronger impact is expected in the upcoming LHC Run III and HL-LHC as compared to the current LHC, mainly due to the increased bunch intensity. Its criticality and mitigation methods are discussed. It is shown that symmetric quenches in the superconducting magnets for the final focusing triplet can have a significant impact on the beam on short timescales. The impact on the beam due to failures of the beam-beam compensating wires as well as coherent excitations by the transverse beam damper are also discussed.

An energy of 362 MJ is stored in each of the two LHC proton beams for nominal beam parameters. This will be further increased to about 700 MJ in the future high luminosity LHC (HL-LHC) and uncontrolled beam losses represent a significant hazard for the integrity and safe operation of the machine. In this paper, a number of failure mechanisms that can lead to a fast increase of beam losses are analyzed. Most critical are failures in the magnet protection system, namely the quench heaters and a novel protection system called coupling-loss induced quench (CLIQ). An important outcome is that magnet protection has to be evaluated for its impact on the beam and designed accordingly. In particular, CLIQ, which is to protect the new HL-LHC triplet magnets, constitutes the fastest known failure in the LHC if triggered spuriously. A schematic change of CLIQ to mitigate the hazard is presented. A loss of the beam-beam kick due to the extraction of one beam is another source of beam losses with a fast onset. A significantly stronger impact is expected in the upcoming LHC Run III and HL-LHC as compared to the current LHC, mainly due to the increased bunch intensity. Its criticality and mitigation methods are discussed. It is shown that symmetric quenches in the superconducting magnets for the final focusing triplet can have a significant impact on the beam on short timescales. The impact on the beam due to failures of the beam-beam compensating wires as well as coherent excitations by the transverse beam damper are also discussed.

The European Organization for Nuclear Research (CERN) and U.S. LHC Accelerator Research Program (LARP) are jointly developing Nb-3Sn quadrupole magnets to be installed in the LHC for its upgrade to higher luminosity. These magnets' quench protection system will include a combination of quench heaters attached to the coil surfaces and coupling-loss-induced quench (CLIQ) units electrically connected to the magnets. Different protection elements have been characterized separately and simultaneously by implementing them on two 1.2-m-long model quadrupole magnets, tested at Fermi National Acceleration Laboratory and CERN, and one 4-m-long mirror magnet tested at Brookhaven Nation Laboratory. After analyzing the test data, their performances have been positively evaluated. Furthermore, the electrothermal transients occurring after a quench have been simulated with the LEDET software and the results are compared to experimental results. The preferred quench protection system configuration relies both on heaters and CLIQ. This solution is based on electrically robust components, achieves an effective reduction of the coils hot spot temperature after a quench, and offers increased redundancy against component failures.

The European Organization for Nuclear Research (CERN) and U.S. LHC Accelerator Research Program (LARP) are jointly developing Nb-3Sn quadrupole magnets to be installed in the LHC for its upgrade to higher luminosity. These magnets' quench protection system will include a combination of quench heaters attached to the coil surfaces and coupling-loss-induced quench (CLIQ) units electrically connected to the magnets. Different protection elements have been characterized separately and simultaneously by implementing them on two 1.2-m-long model quadrupole magnets, tested at Fermi National Acceleration Laboratory and CERN, and one 4-m-long mirror magnet tested at Brookhaven Nation Laboratory. After analyzing the test data, their performances have been positively evaluated. Furthermore, the electrothermal transients occurring after a quench have been simulated with the LEDET software and the results are compared to experimental results. The preferred quench protection system configuration relies both on heaters and CLIQ. This solution is based on electrically robust components, achieves an effective reduction of the coils hot spot temperature after a quench, and offers increased redundancy against component failures.

The goal of the High Luminosity LHC project is upgrading the LHC in order to increase its luminosity by a factor of five. To achieve this, 24 150-mm-aperture 12-T Nb 3Sn quadrupole magnets are to be installed close to the two interaction regions at ATLAS and CMS. This new generation of high-field magnets poses a significant challenge concerning the protection of the coils in the case of a quench. The very high stored energy per unit volume requires a fast and effective quench heating system in order to limit the hot-spot temperature and hence avoid damage due to overheating. Conventional protection systems based on quench heaters have a limited response time due to the thermal insulation between the heater and the coil. An advanced solution for the protection of high-field magnets is the coupling-loss induced quench (CLIQ) system, recently developed at CERN. Due to its fast intrawire energy-deposition mechanism, CLIQ is a very effective, yet electrically robust, quench protection system. Various protection scenarios, including quench heaters, CLIQ, or combinations of the two methods, are analyzed and discussed, with the aim of minimizing the coil's hot-spot temperature and thermal gradients during the discharge. The proposed design assures a fully redundant system.

The goal of the High Luminosity LHC project is upgrading the LHC in order to increase its luminosity by a factor of five. To achieve this, 24 150-mm-aperture 12-T Nb 3Sn quadrupole magnets are to be installed close to the two interaction regions at ATLAS and CMS. This new generation of high-field magnets poses a significant challenge concerning the protection of the coils in the case of a quench. The very high stored energy per unit volume requires a fast and effective quench heating system in order to limit the hot-spot temperature and hence avoid damage due to overheating. Conventional protection systems based on quench heaters have a limited response time due to the thermal insulation between the heater and the coil. An advanced solution for the protection of high-field magnets is the coupling-loss induced quench (CLIQ) system, recently developed at CERN. Due to its fast intrawire energy-deposition mechanism, CLIQ is a very effective, yet electrically robust, quench protection system. Various protection scenarios, including quench heaters, CLIQ, or combinations of the two methods, are analyzed and discussed, with the aim of minimizing the coil's hot-spot temperature and thermal gradients during the discharge. The proposed design assures a fully redundant system.

We have recently described the antiviral effect in mice of in vitro-transcribed RNAs mimicking structural domains in the non-coding regions of the foot-and-mouth disease virus (FMDV) genome RNA. These small, synthetic and non-infectious RNA molecules (ncRNAs) are potent type-I interferon (IFN) inducers in vivo. In this work, the immunomodulatory effect of the ncRNA corresponding to the internal ribosome entry site (IRES) on immunization with two different FMD vaccine formulations, both based on inactivated virus, including or not a commercial adjuvant, was analyzed in the mice model. The effect of the time interval between RNA inoculation and immunization was also studied. RNA delivery consistently increased the titers of specific anti-FMDV antibodies, including neutralizing antibodies, elicited after vaccination. Moreover, at day 2 after immunization, significant differences in mean antibody titers could be detected between the groups of mice receiving either vaccine co-administered with the RNA and the control group, unlike those immunized with the vaccine alone. When vaccinated mice were challenged with FMDV, the mean values of viral load were lower in the groups receiving the RNA together with the vaccine. Our results show the enhancing effect of the IRES RNA on the immune response elicited after vaccination and suggest the potential of this molecule as an adjuvant for new FMD vaccine design. © 2013 Elsevier Ltd.

Las patologías que se originan en pizarra para cubiertas son debidas fundamentalmente a la presencia de materiales alterables (sulfuros de hierro, carbonatos y materia orgánica). Estos minerales pueden llegar a alterarse por efecto de los agentes medioambientales, una vez que la pizarra es puesta en obra. Las patologías están principalmente asociadas a procesos de oxidación y yesificación de las citadas fases minerales. En este trabajo se determinan las patologías potenciales de varias pizarras para cubiertas españolas, utilizando los ensayos definidos en las normas UNE-EN 12326:2005, 14147:2004 y 11597:2007., The pathologies formed in slate roofs are mainly due to the presence of potentially unstable minerals (iron sulfides, carbonates and organic matter). These minerals may become altered by the effect of environmental agents, once the slate roof is finished. The pathologies are mainly associated with oxidation and gypsification processes of the cited mineral phases. In this work, the potential pathologies of several Spanish roofing slates are identified, using the tests defined in the European Norms EN 12326:2005, 14147:2004 and 11597:2007.

Noroviruses (NoVs) are responsible for the majority of gastroenteritis outbreaks in humans. Recently, NoV strains which are genetically closely related to human genogroup II (GII) NoVs have been detected in fecal specimens from swine. These findings have raised concern about the possible role of pigs as reservoirs for NoVs that could infect humans. To better understand the epidemiology of swine NoVs in both the swine and the human populations, rapid immunoassays are needed. In this study, baculovirus recombinants were generated to express the capsid gene of a swine NoV GII genotype 11 (GII.11) strain which self-assembled into virus-like particles (VLPs). Subsequently, the purified VLPs were used to evoke monoclonal antibodies (MAbs) in mice. A panel of eight promising MAbs was obtained and evaluated for their ability to bind to heterologous VLPs, denaturated antigens, and truncated capsid proteins. The MAbs could be classified into two groups: two MAbs that recognized linear epitopes located at the amino-terminal half (shell domain) of the swine NoV GII.11 VLPs and that cross-reacted with human GII.4 NoV VLPs. The other six MAbs bound to conformational epitopes and did not cross-react with the human GII.4 VLPs. To our knowledge, this is the first report on the characterization of MAbs against swine NoVs. The swine NoV VLPs and the MAbs described here may be further used for the design of diagnostic reagents that could help increase our knowledge of the prevalence of NoV infections in pigs and the possible role of pigs as reservoirs for NoVs.

Se estudia un procedimiento para la obtención de Biodiesel a partir de las “Oleínas”. Biodiesel es un producto capaz de sustituir al combustible Diesel ordinario que se obtiene del petróleo y que consiste en una mezcla de ésteres metílicos de ácidos grasos. Las oleínas son unos residuos que resultan del proceso de refina- do de aceites vegetales para su uso alimentario y se componen de una mezcla de triglicéridos y ácidos grasos libres, con un con- tenido de estos últimos componentes superior al 50% . El merca- do de oleinas es fluctuante, con lo que en ocasiones surge el problema de su eliminación. Como resultado del trabajo efectua- do se define un proceso de obtención que consta de las siguien- tes etapas: 1. Esterificación de los ácidos libres de la Oleína con meta- nol, aplicando catálisis ácida, centrifugando el producto obtenido y separándolo de la fase metanol-ácido. En ésta etapa se obtiene un producto que contiene alrededor de un 70% de metil- esteres. 2. Transesterificación de los triglicéridos presentes en el producto esterificado con metanol, aplicando catálisis alcalina. El producto obtenido, previamente separado de la fase metanol- agua, contiene alrededor de un 90% de metil-esteres. 3. Purificación del producto resultante de las etapas 1 y 2 , por rectificación a vacío. El producto destilado tiene un contenido en metil-esteres superior al 98%., A procedure to obtain Biodiesel from “Oleinas” is studied. Biodiesel is a suitable product to replace diesel oil currently used to power the Diesel engines. It consists of a mixture of methyl esters of the fatty acids presents as triglycerides in vegetables oils (olive, sunflower, soya, rape oils). As a result of the refining of these oils for their use as food, a waste product is formed, the “oleinas” (acidulated soapstock). The oleinas consist of a mixture of triglycerides and free fatty acids, the latter amounting to 50% or more of the mixture and are subject to a fluctuating market, therefore it exist at times a problem for their disposal. In our research work we have tried to obtain biodiesel from oleinas. The process resulting from our experimental work is as follows: 1. Sterification of the free fatty acids with methanol, by acid catalysis, centrifuging the reaction product and removal of the acid-methanol phase. Drying of the latter. At this stage we have a product containing about 70% of methyl esters. 2. Transesterification of the triglycerides present in the sterified product with methanol by alkaline catalysis, washing the reaction product with a water methanol solution. Centrifuging and removal of the water-methanol phase. At this stage a biodiesel product is obtained containing about 90% of methyl esters. 3. Fractional vacuum distillation of the 90% biodiesel gives a final product with a methyl esters content higher than 98%.

Se estudia un procedimiento para la obtención de Biodiesel a partir de las “Oleínas”. Biodiesel es un producto capaz de sustituir al combustible Diesel ordinario que se obtiene del petróleo y que consiste en una mezcla de ésteres metílicos de ácidos grasos. Las oleínas son unos residuos que resultan del proceso de refina- do de aceites vegetales para su uso alimentario y se componen de una mezcla de triglicéridos y ácidos grasos libres, con un con- tenido de estos últimos componentes superior al 50% . El merca- do de oleinas es fluctuante, con lo que en ocasiones surge el problema de su eliminación. Como resultado del trabajo efectua- do se define un proceso de obtención que consta de las siguien- tes etapas: 1. Esterificación de los ácidos libres de la Oleína con meta- nol, aplicando catálisis ácida, centrifugando el producto obtenido y separándolo de la fase metanol-ácido. En ésta etapa se obtiene un producto que contiene alrededor de un 70% de metil- esteres. 2. Transesterificación de los triglicéridos presentes en el producto esterificado con metanol, aplicando catálisis alcalina. El producto obtenido, previamente separado de la fase metanol- agua, contiene alrededor de un 90% de metil-esteres. 3. Purificación del producto resultante de las etapas 1 y 2 , por rectificación a vacío. El producto destilado tiene un contenido en metil-esteres superior al 98%., A procedure to obtain Biodiesel from “Oleinas” is studied. Biodiesel is a suitable product to replace diesel oil currently used to power the Diesel engines. It consists of a mixture of methyl esters of the fatty acids presents as triglycerides in vegetables oils (olive, sunflower, soya, rape oils). As a result of the refining of these oils for their use as food, a waste product is formed, the “oleinas” (acidulated soapstock). The oleinas consist of a mixture of triglycerides and free fatty acids, the latter amounting to 50% or more of the mixture and are subject to a fluctuating market, therefore it exist at times a problem for their disposal. In our research work we have tried to obtain biodiesel from oleinas. The process resulting from our experimental work is as follows: 1. Sterification of the free fatty acids with methanol, by acid catalysis, centrifuging the reaction product and removal of the acid-methanol phase. Drying of the latter. At this stage we have a product containing about 70% of methyl esters. 2. Transesterification of the triglycerides present in the sterified product with methanol by alkaline catalysis, washing the reaction product with a water methanol solution. Centrifuging and removal of the water-methanol phase. At this stage a biodiesel product is obtained containing about 90% of methyl esters. 3. Fractional vacuum distillation of the 90% biodiesel gives a final product with a methyl esters content higher than 98%.

Se estudia un procedimiento para la obtención de Biodiesel a partir de las “Oleínas”. Biodiesel es un producto capaz de sustituir al combustible Diesel ordinario que se obtiene del petróleo y que consiste en una mezcla de ésteres metílicos de ácidos grasos. Las oleínas son unos residuos que resultan del proceso de refina- do de aceites vegetales para su uso alimentario y se componen de una mezcla de triglicéridos y ácidos grasos libres, con un con- tenido de estos últimos componentes superior al 50% . El merca- do de oleinas es fluctuante, con lo que en ocasiones surge el problema de su eliminación. Como resultado del trabajo efectua- do se define un proceso de obtención que consta de las siguien- tes etapas: 1. Esterificación de los ácidos libres de la Oleína con meta- nol, aplicando catálisis ácida, centrifugando el producto obtenido y separándolo de la fase metanol-ácido. En ésta etapa se obtiene un producto que contiene alrededor de un 70% de metil- esteres. 2. Transesterificación de los triglicéridos presentes en el producto esterificado con metanol, aplicando catálisis alcalina. El producto obtenido, previamente separado de la fase metanol- agua, contiene alrededor de un 90% de metil-esteres. 3. Purificación del producto resultante de las etapas 1 y 2 , por rectificación a vacío. El producto destilado tiene un contenido en metil-esteres superior al 98%., A procedure to obtain Biodiesel from “Oleinas” is studied. Biodiesel is a suitable product to replace diesel oil currently used to power the Diesel engines. It consists of a mixture of methyl esters of the fatty acids presents as triglycerides in vegetables oils (olive, sunflower, soya, rape oils). As a result of the refining of these oils for their use as food, a waste product is formed, the “oleinas” (acidulated soapstock). The oleinas consist of a mixture of triglycerides and free fatty acids, the latter amounting to 50% or more of the mixture and are subject to a fluctuating market, therefore it exist at times a problem for their disposal. In our research work we have tried to obtain biodiesel from oleinas. The process resulting from our experimental work is as follows: 1. Sterification of the free fatty acids with methanol, by acid catalysis, centrifuging the reaction product and removal of the acid-methanol phase. Drying of the latter. At this stage we have a product containing about 70% of methyl esters. 2. Transesterification of the triglycerides present in the sterified product with methanol by alkaline catalysis, washing the reaction product with a water methanol solution. Centrifuging and removal of the water-methanol phase. At this stage a biodiesel product is obtained containing about 90% of methyl esters. 3. Fractional vacuum distillation of the 90% biodiesel gives a final product with a methyl esters content higher than 98%.

Se estudia un procedimiento para la obtención de Biodiesel a partir de las “Oleínas”. Biodiesel es un producto capaz de sustituir al combustible Diesel ordinario que se obtiene del petróleo y que consiste en una mezcla de ésteres metílicos de ácidos grasos. Las oleínas son unos residuos que resultan del proceso de refina- do de aceites vegetales para su uso alimentario y se componen de una mezcla de triglicéridos y ácidos grasos libres, con un con- tenido de estos últimos componentes superior al 50% . El merca- do de oleinas es fluctuante, con lo que en ocasiones surge el problema de su eliminación. Como resultado del trabajo efectua- do se define un proceso de obtención que consta de las siguien- tes etapas: 1. Esterificación de los ácidos libres de la Oleína con meta- nol, aplicando catálisis ácida, centrifugando el producto obtenido y separándolo de la fase metanol-ácido. En ésta etapa se obtiene un producto que contiene alrededor de un 70% de metil- esteres. 2. Transesterificación de los triglicéridos presentes en el producto esterificado con metanol, aplicando catálisis alcalina. El producto obtenido, previamente separado de la fase metanol- agua, contiene alrededor de un 90% de metil-esteres. 3. Purificación del producto resultante de las etapas 1 y 2 , por rectificación a vacío. El producto destilado tiene un contenido en metil-esteres superior al 98%., A procedure to obtain Biodiesel from “Oleinas” is studied. Biodiesel is a suitable product to replace diesel oil currently used to power the Diesel engines. It consists of a mixture of methyl esters of the fatty acids presents as triglycerides in vegetables oils (olive, sunflower, soya, rape oils). As a result of the refining of these oils for their use as food, a waste product is formed, the “oleinas” (acidulated soapstock). The oleinas consist of a mixture of triglycerides and free fatty acids, the latter amounting to 50% or more of the mixture and are subject to a fluctuating market, therefore it exist at times a problem for their disposal. In our research work we have tried to obtain biodiesel from oleinas. The process resulting from our experimental work is as follows: 1. Sterification of the free fatty acids with methanol, by acid catalysis, centrifuging the reaction product and removal of the acid-methanol phase. Drying of the latter. At this stage we have a product containing about 70% of methyl esters. 2. Transesterification of the triglycerides present in the sterified product with methanol by alkaline catalysis, washing the reaction product with a water methanol solution. Centrifuging and removal of the water-methanol phase. At this stage a biodiesel product is obtained containing about 90% of methyl esters. 3. Fractional vacuum distillation of the 90% biodiesel gives a final product with a methyl esters content higher than 98%.

The process, which proceeds at a very slow rate, can be improved by performing separately the two operations relating to the two effects involved in the indirect contact mechanism: chemical leaching and biological oxidation of the Fe2+ produced. Chemical leaching of the concentrate can be carried out so that preferential dissolution of zinc with respect to copper is achieved. The addition of a small proportion of a silver salt to the ferric leaching solution increases the rate of Cu leaching and decreases that of Zn. The silver used in the process can be recovered by transferring it from the chalcopyrite leached residue to the chalcopyrite concentrate to be leached., The process, which proceeds at a very slow rate, can be improved by performing separately the two operations relating to the two effects involved in the indirect contact mechanism: chemical leaching and biological oxidation of the Fe2+ produced. Chemical leaching of the concentrate can be carried out so that preferential dissolution of zinc with respect to copper is achieved. The addition of a small proportion of a silver salt to the ferric leaching solution increases the rate of Cu leaching and decreases that of Zn. The silver used in the process can be recovered by transferring it from the chalcopyrite leached residue to the chalcopyrite concentrate to be leached.

The rate of leaching of chalcopyrite decrease with time, apparently as the result of the formation of a passivating layer consisting of a sulphide or polysulphide reaction product (rather than of elemental sulphur). Reactivation could be acheived by precipitating sulphides (preferably of Ag, Hg or As) on to the passivated surface., The rate of leaching of chalcopyrite decrease with time, apparently as the result of the formation of a passivating layer consisting of a sulphide or polysulphide reaction product (rather than of elemental sulphur). Reactivation could be acheived by precipitating sulphides (preferably of Ag, Hg or As) on to the passivated surface.