Selective oxidation of sulfides to sulfoxides and sulfones using a new catalyst with Keggin type-structure (H5PMo11Al0.5V0.5O40)

En esta investigación, se ha encontrado un nuevo y selectivo procedimiento de oxidación de sulfuros aromáticos y alifáticos, en sulfóxidos y sulfonas, empleando 35% H2O2 y acetonitrilo como solvente de reacción. Esta oxidación selectiva se realiza en presencia de cantidades catalíticas de un nuevo heteropoliácido, H5PMo11Al0.5V0.5O40, con estructura tipo Keggin. Los rendimientos fueron excelentes y todos los reactivos son baratos y de fácil acceso. La reacción para la preparación de sulfóxidos fue llevada a cabo a temperatura ambiente y a cortos tiempos. La oxidación a sulfotas procede a 40 C dando también excelentes rendimientos.In this research, a new and selective procedure for the oxidation of sulfides, aromatics and aliphatics, to sulfoxides and sulfones, with 35 % aqueous H2O2 and acetonitrile as solvent. Catalytic amount of new Keggin heteropolyacid H5PMo11Al0.5V0.5O40 were used. The yields were excellent and all reagents are cheap and easily available. The reaction for preparation of sulfoxides was carried out at room temperature and short times. The oxidation to sulfones proceeded at 40 °C in also excellent yields.Fil: Romanelli, Gustavo Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo En Ciencias Aplicadas "Dr. Jorge J. Ronco". Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Ciencias Aplicadas; ArgentinaFil: Vazquez, Patricia Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo En Ciencias Aplicadas "Dr. Jorge J. Ronco". Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Ciencias Aplicadas; ArgentinaFil: Dimitroff, Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo En Ciencias Aplicadas "Dr. Jorge J. Ronco". Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Ciencias Aplicadas; ArgentinaFil: Tundo, Pietro. Consorzio Interuniversitario Nazionale La Chimica per l; Itali

Toward Autonomous Guidance and Control: A Robust AI-Based Solution for Low-Thrust Orbit Transfers

The focus of our initial application scenario centers around a low-thrust orbit transfer in Low-Earth Orbit (LEO). This specific use-case has been chosen due to its inherent challenges, including the requirements for robustness and real-time computation. We propose an AI-based solution capable of autonomous and robust on-board G&C. The core of our approach leverages a Deep Neural Network (DNN) trained through Reinforcement Learning (RL) techniques. Our method aims at enhancing a traditional guidance approach by managing environmental perturbations, it processes the on-board navigation coordinates and provides the thrust to be imposed by the propulsion subsystem. Our approach demonstrates effectiveness in performing maneuvers changing semi-major axis (SMA), eccentricity (ECC), and inclination (INC), operating continuously with a control horizon of several days. Robustness is tested by using physical model uncertainties, introducing disturbances in the mission coordinates, and injecting perturbations in subsystems

MATERIALS SELECTION AND DEVELOPMENT FOR CENTRIFUGAL COMPRESSORS OPERATING IN EXTREME SOUR & ACID GAS SERVICE

TutorialThe rising demand for oil and gas has led us to exploit oil fields and gas reservoirs with increasing amounts of contaminants. Reserves of natural gas are abundant, but about 40% of the fields contain high concentrations of hydrogen sulfide, carbon dioxide, and chlorides. The harshening environment represents a challenge for the suitability of common classes of materials used for design and manufacturing of centrifugal compressor components. According to NACE MR0175/ISO15156, a fit-for-purpose approach has been extensively used to prove the steel’s resistance in simulated field conditions and characterize the environmental limits of most martensitic and precipitation hardening stainless steels in terms of partial pressure of carbon dioxide, hydrogen sulfide, and chlorides. The literature available on the subject generally agrees that the contaminants’ concentration levels exceed the possibility of risk presented by stainless steels to turbo-machine reliability, and in worst cases to operators’ safety. Nickel-based alloys are the most robust solution to overcome the above limitations, guaranteeing high mechanical strength and resistance against stress corrosion cracking mechanisms in expected compressors’ environments. This paper describes the advance in nickel-based alloys’ application and production of centrifugal compressors (CC) for extreme sour and acid conditions, with work that reveals the development of alternative manufacturing routes for rotor and stator components in turbomachinery. A detailed explanation of nickel-based alloys’ metallurgy, application and manufacturing capability is also given, along with recent developments of new alloys to bridge the gap between iron-base and nickel-base alloys, providing cost effective materials with enhanced corrosion resistance

Sensors and Biosensors for C-Reactive Protein, Temperature and pH, and Their Applications for Monitoring Wound Healing: A Review

Wound assessment is usually performed in hospitals or specialized labs. However, since patients spend most of their time at home, a remote real time wound monitoring would help providing a better care and improving the healing rate. This review describes the advances in sensors and biosensors for monitoring the concentration of C-reactive protein (CRP), temperature and pH in wounds. These three parameters can be used as qualitative biomarkers to assess the wound status and the effectiveness of therapy. CRP biosensors can be classified in: (a) field effect transistors, (b) optical immunosensors based on surface plasmon resonance, total internal reflection, fluorescence and chemiluminescence, (c) electrochemical sensors based on potentiometry, amperometry, and electrochemical impedance, and (d) piezoresistive sensors, such as quartz crystal microbalances and microcantilevers. The last section reports the most recent developments for wearable non-invasive temperature and pH sensors suitable for wound monitoring

Selective oxidation of sulfides to sulfoxides and sulfones using a new catalyst with Keggin type-structure (H5PMo11Al 0.5V0.5O40)

En esta investigación, se ha encontrado un nuevo y selectivo procedimiento de oxidación de sulfuros aromáticos y alifáticos, en sulfóxidos y sulfonas, empleando 35% H2O2 y acetonitrilo como solvente de reacción. Esta oxidación selectiva se realiza en presencia de cantidades catalíticas de un nuevo heteropoliácido, H5PMo11Al0.5V0.5O40, con estructura tipo Keggin. Los rendimientos fueron excelentes y todos los reactivos son baratos y de fácil acceso. La reacción para la preparación de sulfóxidos fue llevada a cabo a temperatura ambiente y a cortos tiempos. La oxidación a sulfotas procede a 40 C dando también excelentes rendimientos.In this research, a new and selective procedure for the oxidation of sulfides, aromatics and aliphatics, to sulfoxides and sulfones, with 35 % aqueous H2O2 and acetonitrile as solvent. Catalytic amount of new Keggin heteropolyacid H5PMo11Al0.5V0.5O40 were used. The yields were excellent and all reagents are cheap and easily available. The reaction for preparation of sulfoxides was carried out at room temperature and short times. The oxidation to sulfones proceeded at 40 °C in also excellent yieldsCentro de Investigación y Desarrollo en Ciencias Aplicada

Non-invasive sensors for wound monitoring and therapy

Chronic wounds such as diabetic foot ulcers and venous leg ulcers affect in Europe more than 10 million people, a number that is expected to grow due to the aging of the population. Sensors can be a valid tool to improve the quality of healthcare for wound monitoring and management. The integration of sensor data within health information and decision support systems may allow the delivery of personalized treatments at decreased cost. The EU FP7 SWAN-iCare project is developing a negative-pressure device associated with non-invasive sensors capable to monitor some physiological parameters related to the wound status, such as pH, temperature and transepidermal water loss. These sensors will help to provide personalized therapies to patients and check the effectiveness of treatments remotely

Temperature-and pH-sensitive wearable materials for monitoring foot ulcers

Foot ulcers account for 15% of comorbidities associated with diabetes. Presently, no device allows the status of foot ulcers to be continuously monitored when patients are not hospitalized. In this study, we describe a temperature and a pH sensor capable of monitoring diabetic foot and venous leg ulcers developed in the frame of the seventh framework program European Union project SWAN-iCare (smart wearable and autonomous negative pressure device for wound monitoring and therapy). Temperature is measured by exploiting the variations in the electrical resistance of a nanocomposite consisting of multiwalled carbon nanotubes and poly(styrene-b-(ethylene-co-butylene)-b-styrene). The pH sensor used a graphene oxide (GO) layer that changes its electrical potential when pH changes. The temperature sensor has a sensitivity of ~85 Ω/°C in the range 25°C-50°C and a high repeatability (maximum standard deviation of 0.1% over seven repeated measurements). For a GO concentration of 4 mg/mL, the pH sensor has a sensitivity of ~42 mV/pH and high linearity (R2=0.99)

MATERIALS SELECTION AND DEVELOPMENT FOR CENTRIFUGAL COMPRESSORS OPERATING IN EXTREME SOUR & ACID GAS SERVICE

TutorialThe rising demand for oil and gas has led us to exploit oil fields and gas reservoirs with increasing amounts of contaminants. Reserves of natural gas are abundant, but about 40% of the fields contain high concentrations of hydrogen sulfide, carbon dioxide, and chlorides. The harshening environment represents a challenge for the suitability of common classes of materials used for design and manufacturing of centrifugal compressor components. According to NACE MR0175/ISO15156, a fit-for-purpose approach has been extensively used to prove the steel’s resistance in simulated field conditions and characterize the environmental limits of most martensitic and precipitation hardening stainless steels in terms of partial pressure of carbon dioxide, hydrogen sulfide, and chlorides. The literature available on the subject generally agrees that the contaminants’ concentration levels exceed the possibility of risk presented by stainless steels to turbo-machine reliability, and in worst cases to operators’ safety. Nickel-based alloys are the most robust solution to overcome the above limitations, guaranteeing high mechanical strength and resistance against stress corrosion cracking mechanisms in expected compressors’ environments. This paper describes the advance in nickel-based alloys’ application and production of centrifugal compressors (CC) for extreme sour and acid conditions, with work that reveals the development of alternative manufacturing routes for rotor and stator components in turbomachinery. A detailed explanation of nickel-based alloys’ metallurgy, application and manufacturing capability is also given, along with recent developments of new alloys to bridge the gap between iron-base and nickel-base alloys, providing cost effective materials with enhanced corrosion resistance

Abuses and Distortions in Emotional Processes as Risk Factors for Parricide

Parricide is a rare case of murder having a strong emotional impact on public opinion, especially when it is heinous and perpetrated by minors. Based on the analysis of the judicial files archived at the Minor Penal Institute "N. Fornelli" of Bari, the authors will report three impressive cases perpetrated by minors, by focusing on their emotional features. Differences between the crimes of parricide committed by adults and minors will be highlighted, by analyzing the peculiar relations between the problems underlying parricide and the role played by abuses and maltreatments experienced by minors perpetrating such crime. In particular, attention will be paid to the emotional processes aroused in minor parricide offenders