bluuebunny/crossref_metadata_2025_split huggingface dataset:
Study on Dynamic Buckling Behavior and Post-Buckling Stability of Thin-Walled Cylinders Subjected to Lateral Vibration
Authors: Ye Yiji , Hasegawa Sho , Kasahara Naoto 
Published: November 2023

Abstract
Severe earthquakes are regarded as Beyond Design Basis Events (BDBEs) in nuclear safety. In the case of buckling of the fast reactor vessel under severe earthquakes, previous research indicated that no immediate collapse occurs due to buckling. Therefore, the objective of safety design of FRV under severe earthquakes is to achieve a stable post-buckling state.
In this paper, dynamic buckling behavior and post-buckling stability of thin-walled cylinders subjected to lateral vibration are studied. It is found that the structural integrity is well maintained after buckling occurrence and thus no threat of major collapse. Firstly, due to phase-inverse phenomenon, the response tends to be stabilized in the out-of-phase region after buckling. In addition, large energy dissipation capacity due to hysteresis behavior prevents the increase of kinematic energy after buckling.
A parametric survey of dominant parameters shows that input acceleration with a low input frequency can cause a more severe destructive effect. Furthermore, the response characteristics under composite sinusoidal excitation and seismic excitation are similar to those of single sinusoidal excitation regarding phase-inverse, acceleration reduction and post-buckling hysteresis behavior.
Effect of Normalizing Temperature on Impact Toughness of ASME SA – 350 LF2 Cl1 Forgings
Authors: Hernández Soto Ricardo , Gómez de Salazar José María 
Published: November 2023

Abstract
Four slabs cut out from a forging ring were normalized at 870°C, 885 °C, 900°C and 915°C for three hours. Cooling from normalizing to room temperature proceeded under forced air. Test specimens were extracted for Charpy impact testing at −46°C and metallographic examination. Furthermore, open-source image analysis software ImageJ was used on SEM micrographs to evaluate the size distribution of pearlite nodules.
The four different normalizing temperatures yielded impact test values above the minimum threshold of SA – 350 for LF2 Cl1 classification. However, the slab normalized at 870 °C showed the best performance, being significantly higher (122 Joules average – 53 Joules minimum) than slab normalized at 915°C (86 Joules average – 33 Joules minimum). Normalizing temperatures of 885°C and 900°C behaved similarly (104 J and 113 J average, respectively).
After the metallographic characterization, it was concluded that higher normalizing temperatures increase the austenite grain size and promote finer pearlites made of single-colony nodules. Lower normalizing temperatures restrict the austenitic grain growth, leading to coarser pearlites made of smaller nodules with multiple colonies. These smaller nodules of coarse pearlite oppose more effectively to brittle crack propagation since colony boundaries function as an additional barrier.
Uncertain Factors in Elastic-Plastic Finite Element Analysis for Elbows and Tees
Authors: Azuma Kisaburo , Fujiwara Keita , Kai Satoru , Otani Akihito , Furuya Osamu 
Published: November 2023

Abstract
Low-cycle fatigue is one of the possible failure modes of piping systems caused by severe earthquakes. Fatigue is a type of cumulative damage during long-term operation; hence, fatigue life evaluation could be critical for the piping systems in existing plants. Considering the fatigue evaluation uncertainty, a considerable margin must be included for the seismic design of the piping systems.
Low-cycle fatigue failure is thought to be associated with the equivalent strain obtained by the elastic-plastic finite element analysis. However, some uncertain factors affect the prediction of the equivalent strain of piping systems, like the actual size and material properties of pipe fittings. These properties are not always readily available in existing plants; therefore, an inevitable uncertainty remains in the analysis. Quantifying the influence of these factors is expected to provide a better understanding of the seismic margin of piping systems.
In this study, we investigate the influence of model assumptions on the equivalent strain range of pipe fittings. We model elbows and equal and reducing tees as the typical pipe fittings used in piping systems. Comparing the results of the elastic-plastic analysis associated with various model assumptions, such as hardening models and structural geometries, we discuss herein how uncertain factors affect the equivalent strain prediction.
Experimental Investigation on Temperature Field Evolution of P280GH Pipeline in Butt Welding Process
Authors: Hu Maiwen , Su Hao , Wang Yanping , Han Zelin , Song Yan 
Published: November 2023

Abstract
It is of great significance to investigate the welding temperature field of pipeline around weld joint during welding process for analyzing the thermal stress and evaluating the performance and service life of welded pipelines. In this work, a pipeline butt welding experiment of P280GH steel was conducted to figure out the evolution of welding temperature field and parameters that affected welding temperature field. 27 effective measuring points were placed at different positions along external and internal surfaces in 3 directions (3, 9, and 12 o’clock directions on the circumference of the cross section). By using the thermocouple temperature measurement method, the welding temperatures for all 37 cycles of the argon arc welding process were monitored and recorded. The results indicate that the most critical parameter of temperature field was the distance from the welding position to measuring point. The temperature rose significantly and then dropped as the welding torch passed by a measuring point. The temperature of the measuring point changed more dramatically as it was closer to the weld joint. With the increase in the number of welding cycles resulting in the superposition of weld metal, the magnitude of temperature evolution at the measuring points on the external surface increased progressively, whereas that on the internal surface decreased gradually.
Hot Spent/Waste Heat Boiler Tube Sheet Reliability Analysis
Authors: Subramanian Kannan , Parker Daniel 
Published: November 2023

Abstract
The tube sheet and several tube-to-tube sheet joints at the flue gas inlet of a hot spent boiler experienced failures in a sulfur processing unit. To address this, plugging of tubes that failed at the joint locations, weld repair on the tube sheet, and post weld heat treatment (PWHT) were performed to bring the boiler back to operation. In addition, a few more tubes were also plugged. In these applications, the selection of tubes to be plugged is based on operator’s historical experience-based information. However, such an approach may not adequately address the mechanical integrity of the unplugged tube-to-tube sheet joints and the tube sheet itself. The repair process adds complexity to the problem that already involves numerous parameters that affect this region of the subject boiler. In this work, a case study of the subject boiler presents a systematic approach involving advanced analytical tools that provided insights into the historical reliability issues and a solution to address tube plugging for continued service. It is demonstrated that such engineering approaches can minimize further failures, repair costs, and loss of production time/costs. It is important to note that many of these boilers were designed to ASME Section I, and may benefit from approaches prescribed in ASME Section VIII, Division I, and design by analysis approaches.
Deterministic Leak-Before-Break Treatment of Uncertainties: Part 2 – Example Application
Authors: Kozluk Michael J. , Al-Dojayli Maher , Pavia Renita , Mileta Ernie 
Published: November 2023

Abstract
The Canadian CANDU® Industry has developed and is implementing a composite analytical approach (CAA) to demonstrate, with high confidence, appropriate safety margins for deterministic nuclear safety analysis of large-break loss-of-coolant accident events in existing CANDU reactors. A key element of the CAA is the deterministic leak-before-break (CAA/DLBB) assessment for postulated through-wall cracks in all butt welds in the large-diameter primary heat transport system piping and reactor headers.
The companion paper proposes an approach to integrate the uncertainties of the key leak-rate parameters into a single metric (a quantitative indicator of the uncertainty in the CAA/DLBB assessment, a.k.a., performance indicator). This approach ensures that the uncertainty in individual key parameters is not taken out of the context of the uncertainty of the other key parameters.
This paper illustrates the application of this systematic approach for quantifying the uncertainty in the CAA/DLBB assessment to a specific postulated break location. The example application illustrates how the bounding values of the key leak-rate factors are quantified and how the uncertainties in the factors are integrated using the analytical and numerical approaches and discuss how the proposed approach provides an unbiased estimate of the leak-rate factor for the postulated break location that is assessed.
Development of a Numerical Framework for Microstructure Sensitive Fatigue Life Investigations
Authors: Henrich Manuel , Dölz Michael , Münstermann Sebastian 
Published: November 2023

Abstract
Modern steel grades with increasingly complex microstructure morphologies demand advanced modeling methods. Especially in terms of geometrical microstructure modeling these steels tend to be very challenging. In this study a framework is presented that tackles the modelling of modern microstructures using a new generator for representative volume elements called DRAGen (Discrete Rve Automation and Generation), and a strategy for the numerical investigation of the influence of the surface roughness and residual stresses on the fatigue life and endurance is proposed. The proposed framework consists mainly of three parts: microstructural characterization, generation of statistical representative volume elements and the investigation of micromechanical behavior under extrinsic loading conditions. The microstructural characterization is supported by neural networks while the generation algorithms of the representative volume elements uses the information generated by those neural networks. The mechanical behavior of these representative volume elements is simulated with Abaqus. Due to the usage of a neural network DRAGen can produce very realistic microstructure models following the statistical behavior of the real world material with a high level of detail. It is also possible to introduce features such as surface roughness and residual stresses into the simulations of DRAGen’s representative volume elements. Therefore, the fatigue life estimations performed with these representative volume elements enable a better understanding of the influences that single microstructural features have on fatigue life. This understanding will help to generate a good basis for numerical optimization of the structural integrity of safety-related components.
Study on the Effect of Local Segregations on the Charpy Impact Toughness Scatter, in RCC-M Code 18 and 20MND5 (SA 508 Gr3) Steel Grade Forgings for Nuclear Components
Authors: Joly Pierre , Roch François , Sun Lingtao , Deneuvillers Elizabeth 
Published: November 2023

Abstract
The microstructure of SA508 Gr3 steel heavy forgings features, in some zones coming from the original ingot where solidification took place with equiaxial grains, local segregations between the solidification grains. These segregations were studied in two different forgings, where the mean local composition is offset from the original heat analysis, at two different levels because of macro-segregation. The local chemical compositions show significant peaks in alloying elements associated with a rather high level of impurity (phosphorus). The resulting structures after forging feature “bands” of segregated material elongated in directions normal to the short direction (perpendicular to the surfaces) of the forging. These structures are analyzed, by metallographical and micro-analytical means. Mechanical testing and fractographic analysis showed that these segregations contribute to brittle fracture initiation in the ductile-brittle transition because of their harder and more brittle character than the surrounding matrix. Because of the relatively large distance between them (several mm) and depending on their random position with respect to the specimen notch tip, significant scatter is observed in the Charpy impact energy. An analysis of the scatter of Charpy impact energy in relation with the position of segregated bands in the ligament and their distance from the specimen notch tip is presented.
A Multi-Scale Creep, Fatigue, and Creep-Fatigue Interaction Model for Estimating Reliability of Steel Components at Elevated Temperatures
Authors: Fong Jeffrey T. , Marcal Pedro V. , Cohn Marvin J. , Heckert N. Alan 
Published: November 2023

Abstract
The American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (BPVC) Committee has recently developed a new Section XI (Nuclear Components Inspection) Division 2 Code named “Reliability and Integrity Management (RIM).” RIM incorporates a new concept known as “System-Based Code (SBC)” originally due to Asada and his colleagues (2001–2004), where an integrated approach from design to service inspection is introduced using three new types of statistical quantities: (1) “system reliability index,” or “system co-reliability target” for any system consisting of structures and components, (2) “structural co-reliability,” for any structure, and (3) “component co-reliability” for any component, where co-reliability is defined as “1 – reliability” and is equal to failure probability. In a recent paper published in the International Journal of Pressure Vessels and Piping (Vol. 173 (2019), pp. 79–93). Fong, Heckert, Filliben, and Freiman developed a new theory of fatigue and creep rupture life modeling for metal alloys at room and elevated temperatures such that the failure probability upper bound (FPUB) of a smooth component can be estimated from fatigue life and creep rupture time test data with simple loading histories. In this paper, we extend the theory to include a methodology to estimate not only the failure probability upper bound, but also the damage state of metal alloy components undergoing creep and fatigue with creep-fatigue interactions. To illustrate our methodology, we present numerical examples based on high temperature creep rupture time test data of stainless steel 316L(N) and room temperature fatigue life test data of AISI 4340 aircraft-quality steel. The significance and limitations of this new damage-state-based approach to modeling creep and fatigue reliability of steel components at elevated temperatures are presented and discussed.
Study on Molten Zone of Butt Fusion Welding Process With Phased Array Ultrasonic Technology for Polyethylene Pipe
Authors: Tao Yangji , Guo Weican , Shi Yan , Miao Cunjian , Tang Ping 
Published: November 2023

Abstract
Butt fusion welding is one of the main methods of connecting polyethylene pipes, widely used in the construction of large diameter thick wall pipes. However, the butt fusion joints are the weak link in the polyethylene pipeline. The butt fusion welding parameters such as the heat plate temperature, heating time and welding pressure affect the properties of welded joints. Previous studies have shown that the welded joint properties are related to the size and shape of the molten zone. The molten zone characteristics can be used to assess the welding process parameters for butt fusion welding. In this study, during the butt fusion welding, the changing state of the molten zone was recorded to obtain the optimal welding process parameters. The real-time video recording of the whole process for polyethylene butt fusion welding was proposed, using ultrasonic phased array focusing and imaging techniques. The ultrasonic signal was detected at the boundary of the molten zone based on the acoustic impedance contrast between the molten and unmolten zones. According to the change of boundary ultrasonic signal, the changing state in the distance of the molten zone was recorded and compared in real time. This experimental method is provided to evaluate the welding process parameters for polyethylene butt fusion welding.
Seismic Design Method of Crossover Piping Across Building Isolation Boundary
Authors: Shibukuwa Kenichi 
Published: November 2023

Abstract
Base-isolated structures for non-nuclear buildings rapidly spreaded after Great Hanshin Earthquake in 1995 and the needs for adopting the base-isolated structure to nuclear power plants have increased since Great East Japan Earthquake in 2011. In the case that base-isolated structure is installed in nuclear power plants, there are technical issues to be addressed such as extreme large anchor movement, design seismic cycle number and buckling failure of vertical component in seismic design of crossover piping across the building isolation boundary, which are supported at many support points. This paper provides specific design methods for crossover piping across the building isolation boundary, such as low cycle fatigue evaluation method by using detail fatigue evaluation method to develop the rational seismic design methods of piping in the future.
Application of Dynamic RBI and IOW Technology in Crude Distillation Unit
Authors: Liu Juanbo , Li Jun , Liu Chang , Han Zhiyuan , Xie Guoshan , Song Libin , Chen Sheng , Kang Haoyuan 
Published: November 2023

Abstract
Crude distillation unit (CDU) generally exists severe corrosion. Risk-based inspection (RBI) technology can effectively assess risk of stationary equipment in petrochemical industry. Meanwhile, integrity operating window (IOW) can effectively control risk by establishing standard and critical limits. Limited of data integrated analysis and the complexity of interfaces connecting in different systems, current risk assessment of complete sets of equipment mainly adopted static method. API 584-2021describes the IOW parameters of the crude distillation unit, but there are few reports about how to apply the dynamic RBI and IOW in the field engineering to achieve real-time risk assessment and warning control of the safety operation boundary. Combining RBI and IOW technology, we recently developed a dynamic risk assessment and IOW warning system by interacting three types dynamic interface data, i.e., medium composition in laboratory information management system (LIMS), real-time process operation parameters in distributed control system (DCS) and equipment thickness in corrosion monitoring system (CMS). The developed system was further applied to the crude distillation unit. Taking three typical corrosion circuits of crude oil circuit before desalting, atmospheric tower overhead circuit and second-line circuit of vacuum tower as examples, the variation of dynamic indicators and risk were investigated. Firstly, the damage modes were analyzed according to API 581 and GB/T 30579. And then the monitoring points including medium compositions, process operation parameters and wall thickness were respectively established by analyzing the corresponding data in LIMS, DCS and CMS. Thus, the risk results will update dynamically with the variations of abovementioned data. Based on dynamic risk results, the critical IOW operation boundaries in typical circuits were also displayed. This research will facilitate grasping the equipment risk state in real-time with dynamic RBI technology while ensuring the equipment steady operation by IOW warning technology.
Life, the genome and everything
Authors: Rosenberg Susan M. 
Published: November 2023

ABSTRACT

In this issue of the
Journal of Bacteriology
, N. J. Bonde, E. A. Wood, K. S. Myers, M. Place, J. L. Keck, and M. M. Cox (J Bacteriol 205:e00184-23, 2023,
https//doi.org/10.1128/jb.00184-23
) used an unbiased transposon-sequencing (Tn-seq) screen to identify proteins required for life when cells lose the RecG branched-DNA helicase (synthetic lethality). The proteins’ identities indicate pathways that prevent endogenous DNA damage, pathways that prevent its homology-directed repair (HDR) “strand-exchange” intermediates between sister chromosomes, and pathways that resolve those intermediates. All avoid intermediate pile-up, which blocks chromosome segregation, causing “death-by-recombination.” DNA damage is managed to regulate crucial but potentially lethal HDR.
The common origin and degenerative evolution of flagella in
Actinobacteria
Authors: Zhu Siqi , Sun Xian , Li Yuqian , Feng Xueyin , Gao Beile 
Published: November 2023

ABSTRACT

Species of the phylum
Actinobacteria
have long time been thought mostly non-motile and non-flagellated, in spite of their extraordinary diversity in morphology, physiology, and ecology. It remains unclear how very few actinobacterial species acquired their flagellar genes and the role of flagellar motility in the evolution of different lineages within this large phylum. Here, we performed a comprehensive phylogenomic analysis of flagellar components in all actinobacterial species, including the deepest branches of this phylum identified recently. Our results provide robust evidence that all actinobacterial flagella shared a common origin and likely evolved from their last common flagellated ancestor by vertical inheritance. Later lineages underwent massive flagellar losses with the ecological switch from aquatic to terrestrial land or host-associated environments. In addition, the actinobacterial flagella also showed degenerative evolution in terms of their composition, leading to the simplest rod known so far. Furthermore, these evolutionary changes of flagella were accompanied by noteworthy variations in the chemosensory system and c-di-GMP mediated signaling network. Overall, we present here a detailed picture of flagellar evolution in
Actinobacteria
, which provides new insights into the evolution of major actinobacterial lineages and previously unobserved links between flagella and other biological features. The simplest flagellar rod as a product of degenerative evolution could possibly serve as a model for future nanomachine reconstruction in synthetic biology.

IMPORTANCE

Flagellar motility plays an important role in the environmental adaptation of bacteria and is found in more than 50% of known bacterial species. However, this important characteristic is sparsely distributed within members of the phylum
Actinobacteria
, which constitutes one of the largest bacterial groups. It is unclear why this important fitness organelle is absent in most actinobacterial species and the origin of flagellar genes in other species. Here, we present detailed analyses of the evolution of flagellar genes in
Actinobacteria
, in conjunction with the ecological distribution and cell biological features of major actinobacterial lineages, and the co-evolution of signal transduction systems. The results presented in addition to clarifying the puzzle of sporadic distribution of flagellar motility in
Actinobacteria
, also provide important insights into the evolution of major lineages within this phylum.
Draft genome sequence of
Lacticaseibacillus rhamnosus
CRL 2244, a strain with strong killing effect on carbapenem-resistant
Acinetobacter baumannii
Authors: Traglia German Matias , Rodriguez Cecilia , Leal Camila , Gasca Briea , Aziz Adiba , Lopez Christina , Petrelli Maria Lucia , Salzameda Nicholas T. , Bonomo Robert A. , Raya Raúl , Ramirez Maria Soledad 
Published: November 2023

ABSTRACT

We report here a draft genome assembly of
Lacticaseibacillus rhamnosus
CRL 2244, recovered from wastewater in Argentina. The genome has a size of 2,898,100 bp, with G + C content of 46.73%. Comparative analysis reveals that its closest relative is
L. rhamnosus
1.0320 (GCF_006151905.1), with an average nucleotide identity of 97.46%.