bluuebunny/crossref_metadata_2025_split huggingface dataset:
On-Sun Characterization of Microchannel Supercritical Carbon Dioxide Solar Thermal Receivers: Preliminary Findings
Authors: Rasouli Erfan , Mande Caton W. , Stevens Matthew M. , Narayanan Vinod 
Published: December 2019

Abstract
The design of, and preliminary on-sun tests on, an 8 cm × 8 cm microchannel supercritical carbon dioxide (sCO2) receiver is presented. The receiver has a laminated design, wherein sheets of Haynes 230 nickel superalloy are patterned and diffusion bonded to form microscale flow passages. The microscale pattern is in the form of square pins with width and height of 500 μm and 200 μm respectively. The pins are arranged in an in-line pattern with respect to the flow direction. The longitudinal and transverse pitch ratios of the micro pin fins are identical and equal to two times the side width of the pillar. A sCO2 test facility is developed with the ability to supply sCO2 at 200 bar pressure and at temperatures between 300–500°C to the receiver inlet. The sCO2 facility is coupled to a seven meter diameter parabolic dish with a 25 kW rating and a concentration ratio of about 800. On-sun tests are performed at a receiver inlet pressure of 150 bar and a receiver inlet temperature between 110–130°C. Receiver and thermal efficiencies in excess of 0.91 and 0.96 respectively for the incident heat flux ranging from 8 to 80 W/cm2, and average surface temperatures ranging from 150–550°C are obtained in these experiments.
Demonstration Reactor System for the Indirect Solar-Thermochemical Reduction of Redox Particles: The Particle Mix Reactor
Authors: Richter Sebastian , Brendelberger Stefan , Gersdorf Felix , Oschmann Tobias , Sattler Christian 
Published: December 2019

Abstract
In contrast to thermal receivers that provide heat for steam cycles, in solar thermochemistry often receiver-reactors are used, where materials undergo a reaction while being irradiated by concentrated sunlight. When applied to two-step redox cycles, multiple processes take place in such receiver-reactors, though on different time scales. This leads to design compromises and to high technical requirements for the implementation. A concept for an indirect particle-based system for thermochemical cycles was therefore proposed in which the heat required for the reduction of redox particles is provided by inert heat transfer particles that absorb concentrated solar radiation in a dedicated particle receiver. The novel and central component in this indirect system is the particle mix reactor. It functions by mixing the two particle types for heat transfer and establishing a controlled atmosphere under decreased oxygen partial pressures in a common reactor chamber.
The design of an experimental setup for demonstration and investigation of the particle mix reactor is presented in this work. Potential operation modes and design options for particle heater, mixing unit and oxygen partial pressure decrease are discussed and illustrated. The selection of a mixer type is based on the homogeneity of the obtained mixture. It is supported by the use of Discrete Element Method (DEM) simulations, which were compared to experimental results from a separate setup. Heat loss estimations for the mixing process in the selected mixer geometry are performed for alumina heat transfer particles and strontium iron oxide redox particles.
The components’ geometries, the overall experimental setup design as well as operation steps are presented.
Risk Assessment in Offshore Salt Caverns to Store CO2
Authors: Pestana Marco Aurelio , Bittencourt Morais Carlos Henrique , da Costa Alvaro Maia , Brandão Camila , Martins Marcelo Ramos 
Published: December 2019

Abstract
Although factual experience of developing offshore salt cavern to CO2 disposal in ultra-deep water is unprecedent, the theme has been gaining relevant attention in Brazil, fueled by the challenges imposed by oil production on the Pre-Salt reservoirs. It is true that some authors have conducted researches related to CO2 disposal on onshore salt caverns, but most of the works regarding salt cavern are related to onshore constructions that are used as methane store to supplement gas consumption during the peak energy demands that historically occurs during the winter season in the North hemisphere. This paper aims to contribute for CO2 disposal research, describing the results obtained from the application of a Preliminary Risk Analysis (PRA) during the conceptual engineering phase of an offshore salt cavern to store CO2 in Brazilian Pre-Salt.
Development of Improved Reaction Technology Blading (RTB LAR) for Large Steam Turbines
Authors: Haller Brian , D’Ovidio Alberto , Henson Jonathan , Beevers Adam , Gupta Abhimanyu 
Published: December 2019

Abstract
The purpose of this paper is to present advances in Reaction Technology Blading design for large steam turbines at Low Aspect Ratio, based on ‘Controlled Flow 2-type’ technology. Reaction technology blading has not previously been evaluated like the impulse blading for improvements from advanced aerodynamic technologies. This paper identifies several unique design improvements and validated by advanced analytical modelling and model turbine testing.
Assessing Prestress Losses in a Nuclear Containment Structure for License Renewal
Authors: Kjolsing Eric , James Randy , Kubischta Keith , Parker Dan 
Published: December 2019

Abstract
Nuclear power plants around the world are nearing the end of their designed service life. Sufficient structural capacity must be demonstrated to extend each plant’s operating license when accounting for concrete creep, shrinkage, and tendon relaxation past the original design life. This may take the form of in-situ values which meet the design allowable or, as outlined in this paper, analysis models which demonstrate capacity.
This paper presents an analysis methodology for a concrete containment structure utilizing grouted post-tensioned tendons representative of a non-US design. The methodology is intended to demonstrate that a structure can still meet established design requirements while accounting for creep, shrinkage, and tendon relaxation. The analysis effort is performed in multiple stages. First, design parameters feeding into post-tensioning loss calculations are identified and assigned statistical distributions. Probabilistic estimates of the post-tensioning losses are developed using both a variational and Monte Carlo approach. Second, a finite element model of a representative containment structure is developed with tendons and reinforcement explicitly modeled. Lastly, the finite element model is used in example analyses to demonstrate future performance and pressure capacity accounting for projected tendon losses.
Size Effects on Thermo-Mechanical Performance of U-10Mo Monolithic Fuel Plates
Authors: Ozaltun Hakan , Roh Hee Seok , Mohamed Walid 
Published: December 2019

Abstract
Monolithic fuel is a fuel form that is considered for the conversion of high performance research reactors. This plate-type fuel consists of a high density U-Mo fuel in monolithic form that is sandwiched between zirconium diffusion barriers, and encapsulated in an aluminum cladding. To date, large number of plates have been irradiated with satisfactory perforamce. The program is now moving into the qualification phase, a predecessor to the timely conversion of the target reactors. It must be shown that the fuel system meets the safety standards and performs well in reactor. The requirement to satisfactory irradiation performance under normal operating conditions is primarily demonstrated by a successful testing. Since each reactor employs distinct fuel plate geometries for various consideration with unique plate design features and attributes, a single “generic” plate geometry capturing all of the extremities is not achievable. Furthermore, testing all these geometric and irradiation parameters on a large size plate is not practical. Therefore, a smaller, “down-scaled” versions of fuel plates, are often employed for experimental purposes. This limitation consequently requires much more cautious performance evaluations, as thermal and mechanical response of a plate with certain geometry may not be representative for a plate with a different geometry. To investigate if plate size has any effects on irradiation performance, the plates with various geometric dimensions were parametrically evaluated. In particular, length and width of the plates were varied between the bounding values. Temperature, deformation, stress values were comparatively evaluated. The results have indicated that effects of geometric ratios and plate size variations in length and width directions are insignificant. However, wider plates could become more prone to a warping-type deformation, if there are nonlinearities.
Running State Assessment for Induced Draft Fans Using Auto Encoder Model Combined With Fuzzy Synthetic
Authors: Yang Jiawei , Hu Di , Yang Tao , Gao Wei , Li Chunmei , Huang Zhihui 
Published: December 2019

Abstract
In order to explore the operation and maintenance characteristics of important auxiliary machines in large-scale power plant coal-fired boilers, a running state assessment model for auxiliary equipment is established. In this paper, taking the complex variability of the operating conditions of thermal power equipment into consider, auto encoder model combined with fuzzy synthetic is proposed. Based on the residual of the model results and the actual power plant operation data, combined with the fuzzy evaluation model to establish a state assessment model, and analyze the actual situation of the induced draft fan of the power plant, to make a real-time assessment of operation status. The evaluation results show the advantages of the state assessment strategy proposed in this paper, and it can reflect the deterioration of the induced draft fan status in time, providing guidance for the operation and maintenance of the equipment.
Experimental Investigation of Thermal Performance of Nano-Enhanced Phase Change Materials for Thermal Management of Electronic Components
Authors: Kothari Rohit , Vaidya Dattaraj V. , Shelke Vinay , Sahu Santosh K. , Kundalwal Shailesh I. 
Published: December 2019

Abstract
Present experimental investigation focuses on implementing passive cooling thermal management technique using heat sinks filled with paraffin wax as phase change material (PCM). Al2O3 nanoparticles are dispersed as thermal conductivity enhancer (TCE) in different weight fractions (φ) for improved performance in the PCM. Unfinned and two finned heat sinks are used in this investigation. Experimental analysis is performed on different configurations of heat sinks and nano-enhanced phase change materials (NePCMs) consisting various weight fraction of Al2O3 nanoparticles (φ = 0%, 0.5%, 4%, and 6%) for a constant heat flux of 2.0 kW/m2. Results show that latent heat and specific heat capacity decreases with increase in the Al2O3 nanoparticle loading. Addition of Al2O3 nanoparticles in the PCM results in the reduced melting time of PCM. While, pure PCM based heat sinks keeps heat sink base temperature lower for longer time duration.
Deflections of Plates in Research Reactor Fuel by Disparities in Thicknesses of Flow Channels
Authors: Bojanowski C. , Solbrekken G. L. , Schnieders G. H. , Rivers J. D. , Wilson E. H. , Foyto L. P. 
Published: December 2019

Abstract
Low-enriched uranium (LEU) fuel element designs for the U.S. high performance research reactors LEU conversion cores have been optimized by each reactor facility to allow the reactors to meet mission, operational, and safety basis requirements using monolithic uranium-molybdenum fuel. As a part of work supporting the Preliminary Safety Analysis Report (PSAR) submitted to the NRC by the University of Missouri Research Reactor (MURR), the impact of thinner 1.12 mm LEU curved fuel plates, compared to the currently used highly-enriched uranium (HEU) curved plate thickness of 1.27 mm, has been assessed for hydro-mechanical performance.
Plate deflection can be induced by the hydrodynamic pressure differential caused by differences in the thicknesses of surrounding coolant flow channels. An experimental study was conducted on relevant Materials Test Reactor-type (MTR-type) reactor plate geometries in a water flow test loop to validate computational models simulating flow-induced plate deflection. Three-dimensional fluid-structure interaction (FSI) simulations of the experiments were performed using several commercially available multi-physics simulation codes. Inclusion of as-built geometry of the plates and channels in the simulations was key to achieving good agreement with measured deflections.
The validated computational methodology was applied to a model of the prototypic MURR LEU plate. For the nominal flow conditions, a small deflection of the plate on the order of 5 micrometers was predicted. That deflection is significantly less than the allowances in the PSAR for change in coolant channel thickness.
The experimental model validation of plate deflection is important since conventional figures of merit for the robustness of MTR-type fuel plates under flow, such as the Miller critical velocity, often show a weak correlation with the prediction of stability. Subsequent to this work, irradiation qualification of the MURR LEU fuel element design has begun and will conclude with a full-size demonstration element test.
Optimizing Natural Gas Combined Cycle Part Load Operation
Authors: Flores Robert , Brouwer Jack 
Published: December 2019

Abstract
The University of California, Irvine (UCI) uses a 19 MW natural gas combined cycle (NGCC) to provide nearly all campus energy requirements. Meanwhile, the University of California system has committed to achieving carbon neutrality at all facilities by 2025. This has resulted in an influx of new energy efficiency and onsite solar generation, increasing the duration of NGCC part load operation. In addition, the shift towards carbon neutrality has resulted in the pursuit of renewable natural gas via anaerobic digestion to replace conventional fossil fuels. The combination of other sources of renewable generation and the shift towards more expensive fuels has created the need to boost NGCC part load performance. This work focuses on the methods used at UCI to explore the NGCC operating space in order to optimize part-load performance. In this work, a physical gas turbine and heat recovery steam generator model are developed and used with an exhaustive search optimization method to predict maximum part load plant efficiency. NGCC control elements considered in this work include gas turbine inlet guide vane modulation and changing combustor outlet temperature. This optimization was also used to explore replacing the current engine with a two-shaft or smaller gas turbine. Results indicate that there are some possible benefits with increased modulation of inlet guide vanes, but the largest efficiency gains are achieved when allowing the compressor to operate at variable speed. Shifting towards a smaller engine could also enable more consistent full power operation, but must be paired with additional resources in order to meet the campus demand.
Reporting specifications regarding epilepsy practice guidelines based on the RIGHT reporting checklist: an analysis
Authors: Wang Zhijie , Zhang Yu , Guo Wei , Hu Xiaoyang Mio , Gao Xiao , Lu Liming 
Published: December 2019

ObjectiveClinical guidelines are designed to optimise patient care and provide efficient approaches for therapy. Epilepsy is a chronic brain disorder that continues to experience a considerable treatment gap due to non-standard recommendations. We assessed the reporting quality of clinical practice guidelines on epilepsy over the past 5 years to generate a reporting specification for this study.SettingSeven databases were searched in May 2018 focusing on the period from 2013 to 2018. These included Medline, EMBASE, PubMed, Cumulative Index to Nursing and Allied Health Literature, China National Knowledge Infrastructure, Wanfang and Chinese Science and Technology Journal Database (VIP). Reporting quality of epilepsy guidelines was assessed by two independent authors using the Reporting Items for practice Guidelines in HealThcare (RIGHT) approach. Spearman’s correlation was used to assess inter-rater reliability.ParticipantsParticipants with epilepsy or seizure, not limited by age, gender, course of disease or cause of epilepsy, were included.InterventionsThere were no limitations with regard to intervention.Primary and secondary outcome measuresThe outcome was the ability of the RIGHT tool to measure reporting quality.ResultsTwelve relevant guidelines were included in this study. The reporting quality was not high in any of the included guidelines. The highest reporting quality included a ‘yes’ proportion of 77.1%, whereas the worst included a corresponding proportion of 37.1%. Overall evaluation results showed that 16.7% of the included guidelines were of high quality, 75% were of medium quality and 8.3% were of low quality. The correlation between the two estimators was credible (ρ>0.7).ConclusionsAppraisal of these guidelines using the RIGHT tool revealed that the quality of reporting varied among guidelines. Items that exhibited low quality in most included guidelines were healthcare questions, rationale/explanation for recommendations, quality assurance, funding source(s) and role(s) of the funder, and limitations of the guideline. Thus, these aspects should receive greater attention in future guideline reporting.
Paediatric chronic fatigue syndrome patients’ and parents’ perceptions of recovery
Authors: Harland Matthew Robert , Parslow Roxanne Morin , Anderson Nina , Byrne Danielle , Crawley Esther 
Published: December 2019

ObjectivesChronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) is common in children and adolescents; however, little is known about how we should define recovery. This study aims to explore perceptions of recovery held by paediatric patients with CFS/ME and their parents.MethodsChildren with CFS/ME and their parents were recruited through a single specialist paediatric CFS/ME service. Data were collected through semistructured interviews with children and parents. The interview questions explored how participants would know if they/their child had recovered from CFS/ME. Thematic analysis was used to identify patterns within the data.ResultsTwenty-one children with CFS/ME, twenty mothers and two fathers were interviewed. Some children found it hard to define recovery as the illness had become a ‘new normal’. Others thought recovery would indicate returning to pre-morbid levels of activity or achieving the same activity level as peers (socialising, education and leisure activities). Increased flexibility in routines and the absence of payback after activities were important. The interviews highlighted the concept of recovery as highly individual with wide variation in symptoms experienced, type and level of activity that would signify recovery. Parents describe how changes in mood and motivation would signify their child’s recovery, but children did not reflect on this.ConclusionSome parents and children struggle to define what would constitute complete recovery. However, signs of recovery were more easily identifiable. Definitions of recovery went far beyond symptom reduction and were focused towards rebuilding lives.
Good staining quality ensuring the reproducibility of Ki67 assessment
Authors: Wang Yeh-Han , Lai Chiung-Ru , Lien Huang-Chun , Hsu Chih-Yi 
Published: December 2019

AimsAlthough Ki67 labelling index (LI) is a prognostic and predictive marker in breast cancer, its accuracy and reproducibility must be validated before its clinical application. We aimed to evaluate the agreement of Ki67 LI in clinical practice in Taiwan.MethodsWe conducted a Ki67 immunohistochemistry (IHC) proficiency test. The participants performed the Ki67 IHC test and measured the Ki67 LI of 10 cases of breast cancer tissue on a microarray slide. The staining quality was centrally reviewed based on the Ki67 staining of the tonsil surface epithelium.ResultsKi67 staining and counting methods are diverse in Taiwan. The reproducibility of Ki67 LI was poor to good (intraclass correlation coefficient: 0.581, 95% CI 0.354 to 0.802). The reproducibility and agreement in the high staining quality group were significantly higher than those in the low staining quality group. The majority of the Ki67 LIs derived from the low staining quality group were underestimated. Different counting methods did not reveal significant differences when determining Ki67 LI with microarray sections.ConclusionsWe suggest using the surface epithelium of the tonsil as external control and achieving optimal staining results that consist of a high positive parabasal layer, a low positive intermediate layer and a negative superficial layer. Good Ki67 staining quality can minimise the staining variations among different laboratories, and it is essential for the reproducibility of Ki67 LI.
Relationship between Insurance Type at Diagnosis and Hepatocellular Carcinoma Survival
Authors: Adler Jaffe Shoshana , Myers Orrin , Meisner Angela L.W. , Wiggins Charles L. , Hill Deirdre A. , McDougall Jean A. 
Published: December 2019

Abstract

Background:
For individuals with hepatocellular carcinoma (HCC), type of insurance may be an important prognostic factor because of its impact on access to care. This study investigates the relationship between insurance type at diagnosis and stage-specific survival.

Methods:
This retrospective cohort analysis used data from 18 Surveillance, Epidemiology, and End Results Program cancer registries. Individuals ages 20 to 64 years, diagnosed with primary HCC between 2010 and 2015, with either private, Medicaid, or no insurance were eligible for cohort inclusion. Adjusted Cox proportional-hazards regression models were used to generate HRs and 95% confidence intervals (CI) for associations between insurance type at diagnosis and overall survival. All models were stratified by stage at diagnosis.

Results:
This analysis included 14,655 cases. Compared with privately insured individuals with the same stage of disease, those with Medicaid had a 43% (HR = 1.43; 95% CI, 1.13–1.32), 22% (HR = 1.22; 95% CI, 1.13–1.32), and 7% higher risk of death for localized, regional, and distant stage, respectively. Uninsured individuals had an 88% (HR = 1.88; 95% CI, 1.65–2.14), 59% (HR = 1.59; 95% CI, 1.41–1.80), and 35% (HR = 1.35; 95% CI, 1.18–1.55) higher risk of death for localized, regional, and distant stage, respectively, compared with privately insured individuals.

Conclusions:
Disparities in survival exist by the type of insurance that individuals with HCC have at the time of diagnosis.

Impact:
These findings support the need for additional research on access to and quality of cancer care for Medicaid and uninsured patients.