Effect of Precipitation on Cryogenic Toughness of N-Containing Austenitic Stainless Steels After Aging

This chapter shows the effect of intergranular precipitation on the cryogenic toughness of N-containing austenitic stainless steels in comparison to that for 316-type austenitic stainless steels. First part of the chapter deals with the thermodynamic stability and growth kinetics of the precipitated phases in the austenite matrix based on Thermo-Calc software. To continue, the experimental evolution of precipitation for N-containing steels is compared to that of 316-type steel and the difference between them are explained based on the Thermo-Calc PRISMA-calculated results. Finally, the effect of intergranular precipitation on the cryogenic fracture toughness is also analyzed using Charpy V‐Notch impact test results. The fracture mode is also related to the precipitation characteristics

Sharing gNB components in RAN slicing: A perspective from 3GPP/NFV standards

To implement the next Generation NodeBs (gNBs) that are present in every Radio Access Network (RAN) slice subnet, Network Function Virtualization (NFV) enables the deployment of some of the gNB components as Virtual Networks Functions (VNFs). Deploying individual VNF instances for these components could guarantee the customization of each RAN slice subnet. However, due to the multiplicity of VNFs, the required amount of virtual resources will be greater compared to the case where a single VNF instance carries the aggregated traffic of all the RAN slice subnets. Sharing gNB components between RAN slice subnets could optimize the trade-off between customization, isolation and resource utilization. In this article, we shed light on the key aspects in the Third Generation Partnership Project (3GPP)/NFV standards for sharing gNB components. First, we identify four possible scenarios for sharing gNB components. Then, we analyze the impact of sharing on the customization level of each RAN slice subnet. Later, we determine the main factors that enable isolation between RAN slice subnets. Finally, we propose a 3GPP/NFV-based description model to define the lifecycle management of shared gNB componentsComment: Article accepted for publication in IEEE Conference on Standards and Networking (CSCN) 201

Application of Phase-Field Method to the Analysis of Phase Decomposition of Alloys

This chapter is focused on the application of the phase-field method to the analysis of phase decomposition during the isothermal aging of alloys. The phase-field method is based on a numerical solution of either the nonlinear Cahn-Hilliard equation or the Cahn-Allen equation. These partial differential equations can be solved using the finite difference method among other numerical methods. The phase-field method has been applied to analyze different types of phase transformations in alloys, such as phase decomposition, precipitation, recrystallization, grain growth, solidification of pure metals and alloys, martensitic transformation, ordering reactions, and so on. One of the main advantages of phase-field method is that this method permits to follow the microstructure evolution in two or three dimensions as the time of phase transformations progresses. Thus, the morphology, size, and size distribution could be determined to follow their corresponding growth kinetics. Additionally, the evolution of chemical composition can also be followed during the phase transformations. Furthermore, both Allen-Cahn and Cahn-Hilliard equations can be solved simultaneously to analyze the presence of ordered phases or magnetic domains in alloys

Fast analysis of relevant contaminants mixture in commercial shellfish

One of the major challenges currently faced is to develop systematic ways of addressing chemical mixtures in environmental assessment. With this purpose, a simple, rapid, and sensitive method for the detection and quantification of a mixture of relevant contaminants in molluscs has been developed. The method is based on QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) and Ultra-High Performance Liquid Chromatography-High Resolution Mass Spectrometry (UHPLC-HRMS). It includes a mixture of 23 compounds formed by pesticides, endocrine disruptors and pharmaceuticals (metolachlor, simazine, desethylatrazine, atrazine, thiabendazole, diazinon, malathion, bentazone, MCPA, propanil, acetamiprid, imidacloprid, caffeine, bisphenol A, triclosan, triclocarban, methylparaben, ethylparaben, propylparaben, 1H-benzotriazole, sulfamethoxazole, venlafaxine and carbamazepine). The method was developed and validated in 4 different types of shellfish of high commercial interest such as mussel (Mytilus galloprovincialis), oyster (Crassostrea gigas), cockle (Cerastoderma edule) and razor shell (Solen marginatus). The mean percentage of recoveries obtained for all the compounds in each mollusc type (intra-specie) ranged from 96% to 107% showing the good performance of the method developed. The relative standard deviation was under 10% for the intra-day and 17% inter-day analyses. Method detection limits and method quantification limits were below 10 ng/g dry weight for all the species and compounds targeted. Finally, the method was applied to aquaculture samples, oysters and cockles, from Ebro Delta (Spain), after some episodes of mortality occurred in 2017. A high level of bisphenol A was detected in C. edule which may explain the mortality suffered by this organism. C. gigas presented low levels of metolachlor, bentazone, acetamiprid, and methylparaben.info:eu-repo/semantics/acceptedVersio

PI3Kα inhibition reduces obesity in mice

Partial inhibition of PI3K is one of the best-validated and evolutionary conserved manipulations to extend longevity. The best known health beneficial effects of reduced PI3K are related to metabolism and include increased energy expenditure, reduced nutrient storage, and protection from obesity. We have previously shown that a dual chemical inhibitor of the alpha and delta PI3K isoforms (CNIO-PI3Ki) reduces obesity in mice and monkeys, without evident toxic effects after long-term treatment. Here, we dissect the role of the alpha and delta PI3K isoforms by making use of selective inhibitors against PI3Kα (BYL-719 also known as alpelisib) or PI3Kδ (GS-9820 also known as acalisib). Treatment of mice with the above mentioned inhibitors indicated that BYL-719 increases energy expenditure in normal mice and efficiently reduces body weight in obese (ob/ob) mice, whereas these effects were not observed with GS-9820. Of note, the dose of BYL-719 required to reduce obesity was 10x higher than the equivalent dose of CNIO-PI3Ki, which could suggest that simultaneous inhibition of PI3K alpha and delta is more beneficial than single inhibition of the alpha isoform. In summary, we conclude that inhibition of PI3Kα is sufficient to increase energy expenditure and reduce obesity, and suggest that concomitant PI3Kα inhibition could play an auxiliary role

Pancreatic Necrosectomy Through a Novel Double-flange Lumen-apposing Covered Metal Stent (Video)

AbstractPancreatic fluid collections (PFCs) represent a complication of acute pancreatitis. Endoscopic management of PFCs is an alternative to surgery [1]. Classic strategies include access to the collection under endoscopic ultrasound (EUS)-guidance and placement of several double-pigtail stents. PFCs containing organized necrosis are classified as walled-off necrosis (WON). In those cases necrosis is hardly evacuated and will require necrosectomy in most cases. Every necrosectomy session needs prior removal of the stents, dilatation of the tract, debridement and placement of new stents adding up a considerable overall cost to the intervention. A novel double-flanged lumen-apposing fully-covered self-expandable metal stent (FC-SEMS) with a 15mm diameter accelerates exit of the necrosis and facilitates multiple necrosectomy sessions.We present a 60 year old patient admitted to the intensive care unit for severe acute pancreatitis that developed WON with superinfection. The intensivists and surgeons indicated endoscopic cystgastrostomy to evacuate the collection. Using the echoendoscope we found a large collection adherent to the gastric wall. The collection was accessed under EUS-guidance using the Hot AXIOS™ catheter that features a cautery tip, then a 15mm AXIOS™ stent was deployed through the cystgastrostomy orifice to keep it patent. The patient required two necrosectomy sessions to clean the cavity. The WON resolved in 6 weeks and the stent was removed unevently. The patient was discharged.A double flange lumen apposing FC-SEMS used as a port for necrosectomy significantly improves management of walled-off pancreatic necrosis. Placement of this stents should be considered when multiple necrosectomy sessions are anticipated. Procedure time can be significantly decreased using a catheter that combines a cautery tip and stent delivery system

Leveraging Geologic CO2 Storage Technology for CO2-EOR Management

Enhanced oil recovery (EOR) through CO2 injection has evolved from the laboratory testing and field piloting phases in the early 1970s to the widespread and refined operations of today. Over the last 20 years, geological CO2 storage (GCS) has emerged as a promising approach to dispose of large volumes of CO2. Much of the early advances in the operational aspects of GCS were learned from CO2-EOR. However, given its “newness� and the health, safety, and environment (HSE) concerns related to CO2 emissions, considerable fundamental and applied research with heavily instrumented GCS field projects, from pilot to commercial scale, has produced data not ordinarily available from conventional CO2-EOR studies. A key exception is the Weyburn-Midale CO2-EOR project in Saskatchewan, Canada, which has had a dedicated characterization, reservoir dynamics and surveillance program in operation since 2000. Even though many of the processes and workflows for these two operations are similar, significant differences do exist primarily because of the different objectives and regulatory environments that exist for CO2-EOR and CO2 storage projects. Fundamentally, CO2 storage tools and processes are geared toward developing a much more detailed understanding of the storage system and the physical and chemical processes accompanying CO2 injection, with monitoring and surveillance being conducted during the pre-operational, operational, and post-operational stages of a project. Pre-operational monitoring for a CO2-EOR project is primarily focused on understanding the reservoir physical and petrophysical properties as well as the properties of the reservoir and injected fluids. Surveillance in the operational phase of an EOR flood is limited, with emphasis being placed on monitoring injection pressures and rates as well as the volumes and properties of the injected and produced fluids. Lessons learned from GCS research and field tests will likely benefit CO2-EOR project performance by employing aspects of characterization, simulation and surveillance. This study reviews the predictive and diagnostic tools currently applied to GCS projects and infers how their deployment might improve CO2-EOR projects. These improvements might include project conformance, CO2 utilization / oil produced, field management, and containment risks.Bureau of Economic Geolog

Temperature-dependence of the hyperfine interaction in the cubic phase of BaHfO₃

The temperature dependence of the hyperfine interaction in the paraelectric phase of BaHfO₃ in the temperature range from liquid-nitrogen temperature to 1350 K has been studied. The experimental results show an Abragam-Pound mechanism for the attenuation of the angular correlation. In this cubic structure the attenuation would be consistent with a relaxation mechanism that involves O-ion hopping between vacant sites in the lattice. Using the point-charge model for the estimation of the electric field gradient produced by an O vacancy in the coordination sphere of the probe ion, the process is characterized by a correlation time τ_(c) = 12 ± 1 ps at RT