Stochastic DES Fault Diagnosis with Coloured Interpreted Petri Nets

[EN] This proposal presents an online method to detect and isolate faults in stochastic discrete event systems without previous model. A coloured timed interpreted Petri Net generates the normal behavior language after an identification stage.The next step is fault detection that is carried out by comparing the observed event sequences with the expected event sequences. Once a new fault is detected, a learning algorithm changes the structure of the diagnoser, so it is able to learn new fault languages. Moreover, the diagnoser includes timed events to represent and diagnose stochastic languages. Finally, this paper proposes a detectability condition for stochastic DES and the sufficient and necessary conditions are proved.This work was supported by a grant from the Universidad del Cauca, Reference 2.3-31.2/05 2011.Muñoz-Añasco, DM.; Correcher Salvador, A.; García Moreno, E.; Morant Anglada, FJ. (2015). Stochastic DES Fault Diagnosis with Coloured Interpreted Petri Nets. Mathematical Problems in Engineering. 2015:1-13. https://doi.org/10.1155/2015/303107S1132015Jiang, S., & Kumar, R. (2004). Failure Diagnosis of Discrete-Event Systems With Linear-Time Temporal Logic Specifications. IEEE Transactions on Automatic Control, 49(6), 934-945. doi:10.1109/tac.2004.829616Zaytoon, J., & Lafortune, S. (2013). Overview of fault diagnosis methods for Discrete Event Systems. Annual Reviews in Control, 37(2), 308-320. doi:10.1016/j.arcontrol.2013.09.009Sampath, M., Sengupta, R., Lafortune, S., Sinnamohideen, K., & Teneketzis, D. (1995). Diagnosability of discrete-event systems. IEEE Transactions on Automatic Control, 40(9), 1555-1575. doi:10.1109/9.412626Sampath, M., Sengupta, R., Lafortune, S., Sinnamohideen, K., & Teneketzis, D. C. (1996). Failure diagnosis using discrete-event models. IEEE Transactions on Control Systems Technology, 4(2), 105-124. doi:10.1109/87.486338Estrada-Vargas, A. P., López-Mellado, E., & Lesage, J.-J. (2010). A Comparative Analysis of Recent Identification Approaches for Discrete-Event Systems. Mathematical Problems in Engineering, 2010, 1-21. doi:10.1155/2010/453254Cabasino, M. P., Giua, A., & Seatzu, C. (2010). Fault detection for discrete event systems using Petri nets with unobservable transitions. Automatica, 46(9), 1531-1539. doi:10.1016/j.automatica.2010.06.013Prock, J. (1991). A new technique for fault detection using Petri nets. Automatica, 27(2), 239-245. doi:10.1016/0005-1098(91)90074-cAghasaryan, A., Fabre, E., Benveniste, A., Boubour, R., & Jard, C. (1998). Discrete Event Dynamic Systems, 8(2), 203-231. doi:10.1023/a:1008241818642Hadjicostis, C. N., & Verghese, G. C. (1999). Monitoring Discrete Event Systems Using Petri Net Embeddings. Application and Theory of Petri Nets 1999, 188-207. doi:10.1007/3-540-48745-x_12Benveniste, A., Fabre, E., Haar, S., & Jard, C. (2003). Diagnosis of asynchronous discrete-event systems: a net unfolding approach. IEEE Transactions on Automatic Control, 48(5), 714-727. doi:10.1109/tac.2003.811249Genc, S., & Lafortune, S. (2003). Distributed Diagnosis of Discrete-Event Systems Using Petri Nets. Lecture Notes in Computer Science, 316-336. doi:10.1007/3-540-44919-1_21Genc, S., & Lafortune, S. (2007). Distributed Diagnosis of Place-Bordered Petri Nets. IEEE Transactions on Automation Science and Engineering, 4(2), 206-219. doi:10.1109/tase.2006.879916Ramirez-Trevino, A., Ruiz-Beltran, E., Rivera-Rangel, I., & Lopez-Mellado, E. (2007). Online Fault Diagnosis of Discrete Event Systems. A Petri Net-Based Approach. IEEE Transactions on Automation Science and Engineering, 4(1), 31-39. doi:10.1109/tase.2006.872120Dotoli, M., Fanti, M. P., Mangini, A. M., & Ukovich, W. (2009). On-line fault detection in discrete event systems by Petri nets and integer linear programming. Automatica, 45(11), 2665-2672. doi:10.1016/j.automatica.2009.07.021Fanti, M. P., Mangini, A. M., & Ukovich, W. (2013). Fault Detection by Labeled Petri Nets in Centralized and Distributed Approaches. IEEE Transactions on Automation Science and Engineering, 10(2), 392-404. doi:10.1109/tase.2012.2203596Basile, F., Chiacchio, P., & De Tommasi, G. (2009). An Efficient Approach for Online Diagnosis of Discrete Event Systems. IEEE Transactions on Automatic Control, 54(4), 748-759. doi:10.1109/tac.2009.2014932Roth, M., Lesage, J.-J., & Litz, L. (2011). The concept of residuals for fault localization in discrete event systems. Control Engineering Practice, 19(9), 978-988. doi:10.1016/j.conengprac.2011.02.008Roth, M., Schneider, S., Lesage, J.-J., & Litz, L. (2012). Fault detection and isolation in manufacturing systems with an identified discrete event model. International Journal of Systems Science, 43(10), 1826-1841. doi:10.1080/00207721.2011.649369Chung-Hsien Kuo, & Han-Pang Huang. (2000). Failure modeling and process monitoring for flexible manufacturing systems using colored timed Petri nets. IEEE Transactions on Robotics and Automation, 16(3), 301-312. doi:10.1109/70.850648Ramirez-Trevino, A., Ruiz-Beltran, E., Aramburo-Lizarraga, J., & Lopez-Mellado, E. (2012). Structural Diagnosability of DES and Design of Reduced Petri Net Diagnosers. IEEE Transactions on Systems, Man, and Cybernetics - Part A: Systems and Humans, 42(2), 416-429. doi:10.1109/tsmca.2011.2169950Cabasino, M. P., Giua, A., & Seatzu, C. (2014). Diagnosability of Discrete-Event Systems Using Labeled Petri Nets. IEEE Transactions on Automation Science and Engineering, 11(1), 144-153. doi:10.1109/tase.2013.2289360Yao, L., Feng, L., & Jiang, B. (2014). Fault Diagnosis and Fault Tolerant Control for Non-Gaussian Singular Time-Delayed Stochastic Distribution Systems. Mathematical Problems in Engineering, 2014, 1-9. doi:10.1155/2014/937583Murata, T. (1989). Petri nets: Properties, analysis and applications. Proceedings of the IEEE, 77(4), 541-580. doi:10.1109/5.24143Dotoli, M., Fanti, M. P., & Mangini, A. M. (2008). Real time identification of discrete event systems using Petri nets. Automatica, 44(5), 1209-1219. doi:10.1016/j.automatica.2007.10.014Muñoz, D. M., Correcher, A., García, E., & Morant, F. (2014). Identification of Stochastic Timed Discrete Event Systems with st-IPN. Mathematical Problems in Engineering, 2014, 1-21. doi:10.1155/2014/835312Latorre-Biel, J.-I., Jiménez-Macías, E., Pérez de la Parte, M., Blanco-Fernández, J., & Martínez-Cámara, E. (2014). Control of Discrete Event Systems by Means of Discrete Optimization and Disjunctive Colored PNs: Application to Manufacturing Facilities. Abstract and Applied Analysis, 2014, 1-16. doi:10.1155/2014/821707Cabasino, M. P., Giua, A., Lafortune, S., & Seatzu, C. (2012). A New Approach for Diagnosability Analysis of Petri Nets Using Verifier Nets. IEEE Transactions on Automatic Control, 57(12), 3104-3117. doi:10.1109/tac.2012.2200372Abdelwahed, S., Karsai, G., Mahadevan, N., & Ofsthun, S. C. (2009). Practical Implementation of Diagnosis Systems Using Timed Failure Propagation Graph Models. IEEE Transactions on Instrumentation and Measurement, 58(2), 240-247. doi:10.1109/tim.2008.200595

Identification of Stochastic Timed Discrete Event Systems with st-IPN

[EN] This paper presents amethod for the identification of stochastic timed discrete event systems, based on the analysis of the behavior of the input and output signals, arranged in a timeline. To achieve this goal stochastic timed interpreted Petri nets are defined.These nets link timed discrete event systems modelling with stochastic time modelling. The procedure starts with the observation of the input/output signals; these signals are converted into events, so that the sequence of events is the observed language. This language arrives to an identifier that builds a stochastic timed interpreted Petri net which generates the same language. The identified model is a deterministic generator of the observed language.The identification method also includes an algorithm that determines when the identification process is over.This work was supported by a Grant from the Universidad del Cauca, reference 2.3-31.2/05 2011.Muñoz-Añasco, DM.; Correcher Salvador, A.; García Moreno, E.; Morant Anglada, FJ. (2014). Identification of Stochastic Timed Discrete Event Systems with st-IPN. Mathematical Problems in Engineering. 2014:1-21. https://doi.org/10.1155/2014/835312S1212014Cassandras, C. G., & Lafortune, S. (Eds.). (2008). Introduction to Discrete Event Systems. doi:10.1007/978-0-387-68612-7Yingwei Zhang, Jiayu An, & Chi Ma. (2013). Fault Detection of Non-Gaussian Processes Based on Model Migration. IEEE Transactions on Control Systems Technology, 21(5), 1517-1526. doi:10.1109/tcst.2012.2217966Ichikawa, A., & Hiraishi, K. (s. f.). Analysis and control of discrete event systems represented by petri nets. Lecture Notes in Control and Information Sciences, 115-134. doi:10.1007/bfb0042308Fanti, M. P., Mangini, A. M., & Ukovich, W. (2013). Fault Detection by Labeled Petri Nets in Centralized and Distributed Approaches. IEEE Transactions on Automation Science and Engineering, 10(2), 392-404. doi:10.1109/tase.2012.2203596Cabasino, M. P., Giua, A., & Seatzu, C. (2010). Fault detection for discrete event systems using Petri nets with unobservable transitions. Automatica, 46(9), 1531-1539. doi:10.1016/j.automatica.2010.06.013Hu, H., Zhou, M., Li, Z., & Tang, Y. (2013). An Optimization Approach to Improved Petri Net Controller Design for Automated Manufacturing Systems. IEEE Transactions on Automation Science and Engineering, 10(3), 772-782. doi:10.1109/tase.2012.2201714Hu, H., Zhou, M., & Li, Z. (2011). Supervisor Optimization for Deadlock Resolution in Automated Manufacturing Systems With Petri Nets. IEEE Transactions on Automation Science and Engineering, 8(4), 794-804. doi:10.1109/tase.2011.2156783Hiraishi, K. (1992). Construction of a class of safe Petri nets by presenting firing sequences. Lecture Notes in Computer Science, 244-262. doi:10.1007/3-540-55676-1_14Estrada-Vargas, A. P., López-Mellado, E., & Lesage, J.-J. (2010). A Comparative Analysis of Recent Identification Approaches for Discrete-Event Systems. Mathematical Problems in Engineering, 2010, 1-21. doi:10.1155/2010/453254Shaolong Shu, & Feng Lin. (2013). I-Detectability of Discrete-Event Systems. IEEE Transactions on Automation Science and Engineering, 10(1), 187-196. doi:10.1109/tase.2012.2215959Li, L., & Hadjicostis, C. N. (2011). Least-Cost Transition Firing Sequence Estimation in Labeled Petri Nets With Unobservable Transitions. IEEE Transactions on Automation Science and Engineering, 8(2), 394-403. doi:10.1109/tase.2010.2070065Supavatanakul, P., Lunze, J., Puig, V., & Quevedo, J. (2006). Diagnosis of timed automata: Theory and application to the DAMADICS actuator benchmark problem. Control Engineering Practice, 14(6), 609-619. doi:10.1016/j.conengprac.2005.03.028Dotoli, M., Fanti, M. P., & Mangini, A. M. (2008). Real time identification of discrete event systems using Petri nets. Automatica, 44(5), 1209-1219. doi:10.1016/j.automatica.2007.10.014Chen, Y., Li, Z., Khalgui, M., & Mosbahi, O. (2011). Design of a Maximally Permissive Liveness- Enforcing Petri Net Supervisor for Flexible Manufacturing Systems. IEEE Transactions on Automation Science and Engineering, 8(2), 374-393. doi:10.1109/tase.2010.2060332Murata, T. (1989). Petri nets: Properties, analysis and applications. Proceedings of the IEEE, 77(4), 541-580. doi:10.1109/5.24143Ramirez-Trevino, A., Ruiz-Beltran, E., Aramburo-Lizarraga, J., & Lopez-Mellado, E. (2012). Structural Diagnosability of DES and Design of Reduced Petri Net Diagnosers. IEEE Transactions on Systems, Man, and Cybernetics - Part A: Systems and Humans, 42(2), 416-429. doi:10.1109/tsmca.2011.2169950Ramirez-Trevino, A., Ruiz-Beltran, E., Rivera-Rangel, I., & Lopez-Mellado, E. (2007). Online Fault Diagnosis of Discrete Event Systems. A Petri Net-Based Approach. IEEE Transactions on Automation Science and Engineering, 4(1), 31-39. doi:10.1109/tase.2006.872120Toutenburg, H. (1974). Fleiss, J. L.: Statistical Methods for Rates and Proportions. John Wiley & Sons, New York-London-Sydney-Toronto 1973. XIII, 233 S. Biometrische Zeitschrift, 16(8), 539-539. doi:10.1002/bimj.19740160814Livingston, E. H., & Cassidy, L. (2005). Statistical Power and Estimation of the Number of Required Subjects for a Study Based on the t-Test: A Surgeon’s Primer. Journal of Surgical Research, 126(2), 149-159. doi:10.1016/j.jss.2004.12.013Ruppert, D. (2011). Statistics and Data Analysis for Financial Engineering. Springer Texts in Statistics. doi:10.1007/978-1-4419-7787-

Autopsia de un body packer al que le habían extraído la droga siendo cadáver

Existen multitud de métodos empleados por los narcotraficantes para el traslado internacional de la droga, siendo el más peligroso para el individuo el transporte en el interior de su organismo, el denominado “body packer”. En ocasiones, alguno de los paquetes puede romperse y provocar la muerte por la salida masiva del tóxico. El hallazgo del envoltorio roto y el resto de paquetes íntegros, con la droga en su interior, al realizar la autopsia, son muy importantes para el diagnóstico. En el caso que nos ocupa, la previa manipulación del cadáver para extracción y recuperación de la droga, ha dificultado la determinación de la causa de la muerte.There are many methods used by drug traffickers for transfer international of drog, being the most dangerous to physical integrity the individual transport inside your body, known “body-packers”. These introduced drugs protected mainly for, arrived destination, extracting it by natural means and deliver it to the receptors, although some of the containers may break inside and cause death by the mass exodus of the toxic. In this case, the autopsy shows the continent broken or defective and other packages intact, with the drug inside. In the present case, the manipulation of the body prior to extraction and recovery of the drug, has made it difficult to determine the cause of deat

Copper(II) complexes of quinoline polyazamacrocyclic scorpiand-type ligands: X-ray, equilibrium and kinetic studies

The formation of Cu(II) complexes with two isomeric quinoline-containing scorpiand-type ligands has been studied. The ligands have a tetraazapyridinophane core appended with an ethylamino tail including 2-quinoline (L1) or 4-quinoline (L2) functionalities. Potentiometric studies indicate the formation of stable CuL2+ species with both ligands, the L1 complex being 3–4 log units more stable than the L2 complex. The crystal structure of [Cu(L1)](ClO4)2·H2O shows that the coordination geometry around the Cu2+ ions is distorted octahedral with significant axial elongation; the four Cu–N distances in the equatorial plane vary from 1.976 to 2.183 Å, while the axial distances are of 2.276 and 2.309 Å. The lower stability of the CuL22+ complex and its capability of forming protonated and hydroxo complexes suggest a penta-dentate coordination of the ligand, in agreement with the type of substitution at the quinoline ring. Kinetic studies on complex formation can be interpreted by considering that initial coordination of L1 and L2 takes place through the nitrogen atom in the quinoline ring. This is followed by coordination of the remaining nitrogen atoms, in a process that is faster in the L1 complex probably because substitution at the quinoline ring facilitates the reorganization. Kinetic studies on complex decomposition provide clear evidence on the occurrence of the molecular motion typical of scorpiands in the case of the L2 complex, for which decomposition starts with a very fast process (sub-millisecond timescale) that involves a shift in the absorption band from 643 to 690 nm

Autopsy on the corpse of a body packer, previously and postmortem emptied by others

Existen multitud de métodos empleados por los narcotraficantes para el traslado internacional de la droga, siendo el más peligroso para el individuo el transporte en el interior de su organismo, el denominado “body packer”. En ocasiones, alguno de los paquetes puede romperse y provocar la muerte por la salida masiva del tóxico. El hallazgo del envoltorio roto y el resto de paquetes íntegros, con la droga en su interior, al realizar la autopsia, son muy importantes para el diagnóstico. En el caso que nos ocupa, la previa manipulación del cadáver para extracción y recuperación de la droga, ha dificultado la determinación de la causa de la muerte.There are many methods used by drug traffickers for transfer international of drug, being the most dangerous to physical integrity the individual transport inside your body, known “body-packers”. These introduced drugs protected mainly for, arrived destination, extracting it by natural means and deliver it to the receptors, although some of the containers may break inside and cause death by the mass exodus of the toxic. In this case, the autopsy shows the continent broken or defective and other packages intact, with the drug inside. In the present case, the manipulation of the body prior to extraction and recovery of the drug has made it difficult to determine the cause of death

Rehabilitación de un espacio eclesial como espacio escénico

Cada vez con más frecuencia nos encontramos con ejemplos de antiguos espacios eclesiales, en avanzado estado de deterioro y abandono, cuya única salida para su conservación es la de albergar usos diferentes para los que fueron concebidos. Es obvio, por tanto, pensar que el comportamiento acústico de dichos espacios no será el más adecuado para las nuevas funciones, probablemente tampoco lo eran para las anteriores, siendo necesario ejecutar algún tipo de actuación que permita conseguir unas condiciones acústicas acordes con el nuevo uso planteado. En este marco se inscribe el proyecto para la rehabilitación y adecuación como espacio escénico de la Iglesia del Antiguo Convento de la Compañía de Jesús en Jerez de la Frontera (Cádiz), financiado por la Gerencia Municipal de Urbanismo, la cual nos planteó desarrollar el estudio acústico del edificio, así como la propuesta de medidas correctoras, para su adecuado comportamiento. Se muestran aquí los aspectos más relevantes de dicho estudio. Ponencia en Encuentro Ibérico de Acústica. EAA Symposium. Expoacústica. Bilbao. 2003.Each time more frecuently, we found examples of antique religious spaces, in advanced conditions of deterioration and forlornness, which the only way to preserve is giving them different uses of what they were designed for. It is obvious, therefore, to think that the acoustic conditions of these spaces are not the most adecuate for its new use and they need to be adapted. With this purpose is designed the Rehabilitation and Adaptation Project of the Church of the Compañía de Jesus Convent in Jerez de la Frontera (Cadiz), which is financed by the Gerencia Municipal de Urbanismo. They ask us to develope the acoustic study of the building and the proposal of the corrective actions for its new use. Here there are the more relevant aspects of this study

Resultados de la corrección acústica de un recinto eclesial tras su rehabilitación como espacio escénico.

Cada vez con más frecuencia, nos encontramos con ejemplos de antiguos espacios eclesiásticos, en avanzado estado de deterioro y abandono, cuya única salida para su conservación es la de albergar usos diferentes de aquellos para los que fueron concebidos. En un trabajo anterior presentamos el estudio previo y las propuestas de actuación correspondientes a uno de estos casos: la rehabilitación y adecuación como espacio escénico, para un uso multifuncional, de la Iglesia del Antiguo Convento de la Compañía de Jesús en Jerez de la Frontera (Cádiz). Una vez concluido el proceso de reforma, estamos en condiciones de comprobar cuál ha sido el resultado y hasta qué punto se han alcanzado los objetivos planteados en la propuesta inicial. Se muestran aquí, en comparación con las previsiones, los aspectos más relevantes de de dicho estudio, apoyándonos en las medidas experimentales realizadas durante y después de la rehabilitación.It’s becoming more and more frequent the case of some ancient ecclesial spaces with advanced injury and withdrawal conditions. To hold their preservation, the only way for these buildings is keeping different applications from those for they were conceived. We have presented in a previous work the foregoing planning and the proceeding motions corresponding to one of these instances: adaptation as scenic space for multifunctional use and rehabilitation in the former Company of Jesus friary in Jerez de la Frontera (Cádiz). With the improvement process concluded, we have the means to check the results and to prove how the initial aims are achieved. We have shown here, beside the foresights, the more outstanding aspects in that study supporting on the experimental measurements made during the rehabilitation and after

Rapid method for radiostrontium determination in milk in emergency situations using PS resin

[EN] This study describes a new and rapid procedure for radiostrontium determination in milk samples based on the use of plastic scintillation resins (PS resins). The proposed method reduces the time of analysis by at least 2 h by combining separation and measurement preparation into a single step and optimizing the pre-treatment steps. The method is robust and reproducible, with good total recoveries (65% on average) and a relative bias for total radiostrontium activity (Sr-89 + Sr-90) below 7%. The minimum detectable activity for 100 mL of milk sample measured for 60 min is about 0.34 Bq L-1. The proposed method can quantify radiostrontium content in 5 h, which makes it suitable for use in emergency situations.The authors are grateful to the Spanish Ministerio de Economia y Competitividad (MINECO) for financial support, under CTM2014-02020 and the Catalan Agencia de Gestio d'Ajuts Universitaris i de Recerca (AGAUR) for financial support, under 2014-SGR-1277. We should also like to thank the Universitat Politecnica de Valencia for finantial support under the "Programa propio para la Formacion de Personal Investigador (FPI) de la UniversitatPolitecnica de Valencia - Subprograma 100.Sáez-Muñoz, M.; Bagán, H.; Tarancón, A.; García, JF.; Ortiz Moragón, J.; Martorell Alsina, SS. (2018). Rapid method for radiostrontium determination in milk in emergency situations using PS resin. Journal of Radioanalytical and Nuclear Chemistry. 315(3):543-555. https://doi.org/10.1007/s10967-017-5682-3S5435553153International Atomic Energy Agency (2015) The fukushima daiichi accident, technical radiological consequences, vol 4. IAEA, ViennaInternational Atomic Energy Agency (2006) Environmental consequences of the chernobyl accident and their remediation: 20 years of experience, Report of the UN Chernobyl forum expert group “environment”, radiological assessment reports Series No. 8, IAEA, ViennaPovinec PP, Hirose K, Aoyama M (2013) Fukushima accident: radioactivity impact on the environment. Elsevier, ChinaCouncil Regulation (Euratom) 2016/52 of 15 January 2016 laying down maximum permitted levels of radioactive contamination of food and feed following a nuclear accident or any other case of radiological emergency, and repealing regulation (Euratom) No 3954/87 and commission regulations (Euratom) No 944/89 and (Euratom) No 770/90Vajda N, Kim CK (2010) Determination of radiostrontium isotopes: a review of analytical methodology. Appl Radiat Isot 68:2306–2326Brun S, Bessac S, Uridat D, Boursier B (2002) Rapid method for the determination of radiostrontium in milk. J Radioanal Nucl Chem 253(2):191–197Maxwell SL, Culligan BK (2009) Rapid method for determination of radiostrontium in emergency milk samples. J Radioanal Nucl Chem 279(3):757–760Kabai E, Hornung L, Savkin BT, Poppitz-Spuhler A, Hiersche L (2011) Fast method and ultra fast screening for determination of 90Sr in milk and dairy products. Sci Total Environ 410–411:235–240International Atomic Energy Agency (2013) Rapid simultaneous determination of 89Sr and 90Sr in milk: a procedure using cerenkov and scintillation counting, analytical quality in nuclear applications no. IAEA/AQ/27, IAEA, ViennaBagán H, Tarancón A, Rauret G, García JF (2011) Radiostrontium separation and measurement in a single step using plastic scintillators plus selective extractants application to aqueous sample analysis. Anal Chim Acta 686:50–56Barrera J, Tarancón A, Bagán H, García JF (2016) A new plastic scintillation resin for single-step separation, concentration and measurement of technetium-99. Anal Chim Acta 936:259–266Lluch E, Barrera J, Tarancón A, Bagán H, García JF (2016) Analysis of 210Pb in water samples with plastic scintillation resins. Anal Chim Acta 940:38–45Santiago L, Tarancón A, García JF (2016) Influence of preparation parameters on the synthesis of plastic scintillation microspheres and evaluation of sample preparation. Adv Powder Technol 27(4):1309–1317Savitzky A, Golay MJE (1964) Smoothing and differentiation of data by simplified least-squares procedures. Anal Chem 36:1627–1639Currie LA (1968) Limits for qualitative detection and quantitative determination. Application to radiochemistry. Anal Chem 40(3):586–593UNE 34829:1983, Determination of the calcium content of milkISO 12081:2010, IDF 36:2010, Milk—Determination of calcium content—titrimetric methodHeckel A, Vogl K (2009) Rapid method for determination of the activity concentrations of 89Sr and 90Sr. Appl Radiat Isot 67:794–796Kabai E, Savkin B, Mehlsam I, Poppitz-Spuhler A (2017) Combined method for the fast determination of pure beta emitting radioisotopes in food samples. J Radioanal Nucl Chem 311:1401–1408Eikenberg J, Beer H, Rüthi M, Zumsteg I, Vetter A (2005) Precise determination of 89Sr and 90Sr/90Y in various matrices: the LSC 3-window approach. LSC2005 Advances in Liquid Scintillation Spectrometry, Radiocarbon, AZ, pp 237–249Kim CK, Al-Hamwi A, Toervenyi A, Kis-Benedek G, Sansone U (2009) Validation of rapid method for the determination of radiostrontium in milk. Appl Radiat Isot 67:786–79

Platinum nanoparticles stabilized by N-heterocyclic thiones. Synthesis and catalytic activity in mono- and di-hydroboration of alkynes

N-Heterocyclic Thiones (NHT) proved to be efficient ligands for the stabilization of small platinum nanoparticles (1.3-1.7 nm), synthesized by decomposition of [Pt(dba)2], under a H2 atmosphere, in the presence of variable sub-stoichiometric amounts of the NHT. Full characterization by means of TEM, HR-TEM, NMR, ICP, TGA and XPS have been carried out, providing information about the nature of the metal nanoparticles and the interaction of the NHT ligands to the metal surface. Importantly, DFT calculations indicate that some NHT ligands interact with the metal through the C[double bond, length as m-dash]C double bond of the imidazole fragment in addition to the sulfur atom, thus providing additional stabilization to the nanoparticles. According to XPS, TGA and ICP techniques, the surface coverage by the ligand increases by decreasing the size of the substituents on the nitrogen atom. The platinum nanoparticles have been used as catalyst in the hydroboration of alkynes. The most active system is that with a less covered surface area lacking an interaction of the ligand by means of the C[double bond, length as m-dash]C double bond. This catalyst hydroborates alkynes with excellent selectivities towards the monoborylated anti-Markovnikov product (vinyl-boronate) when one equiv. of borane is used. Very interestingly, aliphatic alkynes undergo a second hydroborylation process leading to the corresponding 1,1- and 1,2-diboroylated species with good selectivities towards the former.España MINECO (Projects CTQ2016-76267-P, CTQ2016-80814-R and CTQ2016- 81797-REDC)España Junta de Andalucía Project FQM-212