Sensitivity of the neutron multiplication factor to water ingress into a spent fuel cask

Kerntechnik ◽  
2020 ◽  
Vol 85 (1) ◽  
pp. 38-53
Author(s):  
M. J. Leotlela ◽  
I. Petr ◽  
A. Mathye

Abstract An essential component of safety analyses is the investigation of accident scenarios. In this paper water ingress scenarios of spent fuel containers, as they may occur during transport or storage, are examined. In the main body of this paper, a number of paths are studied through which water can gain access to the spent fuel cask and eventually reach the fuel pellet, potentially resulting in an increase in reactivity as a result of over-moderation. The primary objective of this project was to perform an assessment of what, in the unlikely event of a Fukushima- type accident, the impact would be on the reactivity of the cask by analyzing a gradual increase in water level in the spent fuel casks. In addition, the way the keff of the system responds to such an increase is discussed. The paper also provides the results of an assessment of the reactivity effect of water ingress via various pathways/channels.

Author(s):  
Kwang-Il Ahn ◽  
Jae-Uk Shin

The primary purpose of this study is to assess the release of source terms into the environment for representative spent fuel pool (SFP) severe accident scenarios in a reference pressurized water reactor (PWR). For this, two typical accident scenarios (loss-of-cooling and loss-of-pool-inventory accidents) and two different reactor operating modes (normal and refueling modes) are considered in the analysis. The secondary purpose of this study is to assess the impact of an emergency makeup water injection strategy, which is one of representative SFP severe accident mitigation (SAM) strategies being employed after the Fukushima accident, upon the release of the radiological source terms. A total of 16 cases, consisting of four base cases and three injection cases for each base case were simulated using the MELCOR1.8.6 SFP version. The, analysis results are given in terms of (a) the key thermal-hydraulic behaviors during an accident progression and (b) releases of radiological fission products (such as Cesium and Iodine) into the environment. In terms of a release of Cesium and Iodine into the environment, the present study show that the two cases subject to a loss of pool inventory (i.e., LOPI-N-03 and LOPI-R-00) lead to the worst results with the respective release fractions of 77.5% and 59.4%.


Kerntechnik ◽  
2020 ◽  
Vol 85 (1) ◽  
pp. 38-53
Author(s):  
M. J. Leotlela ◽  
I. Petr ◽  
A. Mathye

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
James M. Gerrard ◽  
Shirley Godwin ◽  
Vivienne Chuter ◽  
Shannon E. Munteanu ◽  
Matthew West ◽  
...  

Abstract Background Developing since colonisation, Australia’s healthcare system has dismissed an ongoing and successful First Nations health paradigm in place for 60,000 years. From Captain James Cook documenting ‘very old’ First Nations Peoples being ‘far more happier than we Europeans’ and Governor Arthur Phillip naming Manly in admiration of the physical health of Gadigal men of the Eora Nation, to anthropologist Daisy Bates’ observation of First Nations Peoples living ‘into their eighties’ and having a higher life expectancy than Europeans; our healthcare system’s shameful cultural safety deficit has allowed for an Aboriginal and Torres Strait Islander child born in Australia today to expect to live 9 years less than a non-Indigenous child. Disproportionately negative healthcare outcomes including early onset diabetes-related foot disease and high rates of lower limb amputation in Aboriginal and Torres Strait Islander Peoples contribute to this gross inequity. Main body In 2020, the Australian Health Practitioner Regulation Authority released the National Scheme’s Aboriginal and Torres Strait Islander Health and Cultural Safety Strategy 2020–2025 - empowering all registered health practitioners within Australia to provide health care to Aboriginal and Torres Strait Islander Peoples that is inclusive, respectful and safe, as judged by the recipient of care. This recently released strategy is critically important to the podiatry profession in Australia. As clinicians, researchers and educators we have a collective responsibility to engage with this strategy of cultural safety. This commentary defines cultural safety for podiatry and outlines the components of the strategy in the context of our profession. Discussion considers the impact of the strategy on podiatry. It identifies mechanisms for podiatrists in all settings to facilitate safer practice, thereby advancing healthcare to produce more equitable outcomes. Conclusion Aboriginal and Torres Strait Islander Peoples access health services more frequently and have better health outcomes where provision of care is culturally safe. By engaging with the National Scheme’s Aboriginal and Torres Strait Islander Health and Cultural Safety Strategy, all registered podiatrists in Australia can contribute to achieving equity in health outcomes for Aboriginal and Torres Strait Islander Peoples.


2021 ◽  
pp. 0021955X2110137
Author(s):  
Yao Dou ◽  
Denis Rodrigue

In this study, foamed recycled high density polyethylene (rHDPE) parts were produced by rotational molding using different concentration (0 to 1% wt.) of a chemical blowing agent (CBA) based on azodicarbonamide. From the samples produced, a complete morphological, thermal and mechanical characterization was performed. The morphological analysis showed a gradual increase in the average cell size, while the cell density firstly increased and then decreased with increasing CBA content. As expected, increasing the CBA content decreased the foam density as well as the thermal conductivity. Although increasing the CBA content decreased both tensile and flexural properties, the impact strength showed a similar trend as the cell density with an optimum CBA content around 0.1% wt. Finally, neat rHDPE samples were also produced by compression molding. The results showed negligible differences between the rotomolded and compression molded properties indicating that optimal rotomolding conditions were selected. These results confirm the possibility of using 100% recycled polymers to produce rotomolded foam parts.


Electronics ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 996
Author(s):  
Norshakirah Aziz ◽  
Md Jan Nordin ◽  
Said Jadid Abdulkadir ◽  
Muhammad Muhaimin M. Salih

The advancement of technology has enabled powerful microprocessors to render high-quality graphics for computer gaming. Despite being intended for leisure purposes, several components of the games alongside the gamer’s environmental factors have resulted in digital addiction (DA) towards computer games such as massively multiplayer online games (MMOG). Excessive gaming among adolescents has various negative impacts on an individual. However, only a few researchers have addressed the impact of DA on physical health. Thus, the primary objective of this research is to study the impact of DA on physical health among Malaysian adolescents. This study focuses on Malaysian adolescents of ages 12–18 years old who are addicted to computer games, specifically the MMOG. The methodology used for the study involves focus group discussions (FGD) and extensive literature study. The FGD sessions have involved both medical experts and game experts. The outcome of FGD discussion is recorded and justified with the existing relevant literature from high-impact journals, theses, conferences, books, and reports. This paper provides evidence of five physical health impacts of DA associated with adolescents. The factors of DA, the addiction components existing in MMOG computer games, and the DA health risk assessment are presented in the results section. Based on the study, it is concluded that DA among Malaysian adolescents can cause various impacts on physical health such as obesity, back pain, and neck pain, orthopaedic/joint muscle, eyesight problem, hearing problem, as well as physical inactivity.


2021 ◽  
Vol 56 (2) ◽  
pp. 113-119
Author(s):  
Xinming Xia ◽  
Wan-Hsin Liu

AbstractThis paper analyses how China’s investments in Germany have developed over time and the potential impact of the COVID-19 pandemic in this regard, based on four different datasets, including our own survey in mid-2020. Our analysis shows that Germany is currently one of the most attractive investment destinations for Chinese investors. Chinese state-owned enterprises have played an important role as investors in Germany — particularly in large-scale projects. The COVID-19 pandemic has had some negative but rather temporary effects on Chinese investments in Germany. Germany is expected to stay attractive to Chinese investors who seek to gain access to advanced technologies and know-how in the future.


Vascular ◽  
2020 ◽  
pp. 170853812098369
Author(s):  
Stefano Fazzini ◽  
Giovanni Torsello ◽  
Martin Austermann ◽  
Efthymios Beropoulis ◽  
Roberta Munaò ◽  
...  

Objectives The results of branched endovascular repair of thoracoabdominal aneurysms are mainly dependent on durability of the graft used. The purpose of this study was to evaluate postoperative aortic main body and bridging stent-graft remodeling, and their impact on bridging stent-graft instability at one year. Methods Computed tomoangiographies of 43 patients (43 aortic main body mated with 171 bridging stent-grafts) were analyzed before and after branched endovascular repair as well as after a follow-up of 12 months. Primary endpoint was aortic main body remodeling (migration >5 mm, shortening >5 mm, scoliosis >5° or lordosis >5°). Shortening was defined as a reduced length in the long axis, scoliosis as left-right curvature, and lordosis as antero-posterior curvature. Aortic main body remodeling, aneurysm sac changes, and bridging stent-graft tortuosity were evaluated to study their correlations and the impact on the bridging stent-graft instability. Results At 12 months, aortic main body remodeling was observed in 72% of the cases, migration in 39.5% (mean 5.21 mm), shortening in 41.9% (mean 5.79 mm), scoliosis in 58.1%, (mean 10.10°), lordosis in 44.2% (mean 5.78°). Migration, shortening, and scoliosis were more frequent in patients with larger aneurysms ( p = .005), while scoliosis was significantly more frequent in type II thoracoabdominal aneurysm ( p = .019). Aortic main body remodeling was significantly associated to bridging stent-graft remodeling (r: 0.3–0.48). The bridging stent-graft instability rate was 9.3%. Despite a trend toward significance ( p = .07), none of the evaluated aortic main body and bridging stent-graft changes were associated with bridging stent-graft instability at 12 months. Conclusions Aortic main body remodeling is frequent especially in large and extended thoracoabdominal aneurysm aneurysms. Aortic main body and bridging stent-graft remodeling was significantly correlated. While these geometric changes had no significant impact on bridging stent-graft instability at one year, a close long-term follow-up after branched endovascular repair could predict bridging stent-graft failures.


Stroke ◽  
2021 ◽  
Vol 52 (Suppl_1) ◽  
Author(s):  
Ann Smith ◽  
Kathleen Bledsoe ◽  
Thomas Madden ◽  
Jamie Artale ◽  
Ted Sindlinger

Introduction: The utility of pharmacist-managed collaborative practice agreements (CPA) in the management of hypertension is well established in the outpatient setting. There has been little evaluation of the use of CPAs in the inpatient acute care setting, and none described specifically in the vascular neurology population. Treatment of hypertension is a critical intervention for the secondary prevention of acute ischemic stroke. This quality improvement project evaluated the implementation of a CPA for the inpatient acute care management of hypertension in vascular neurology patients at University of Virginia Health. Methods: A CPA was developed between the neurosciences clinical pharmacist group and the inpatient vascular neurology service, legally vetted, and implemented in June 2019. All vascular neurology patient charts in which an electronic CPA referral was placed from June 2019 through June 2020 were reviewed. Patients were excluded if they were discharged within 24 hours of the referral being placed. The primary objective was to describe and evaluate the implementation of a pharmacist-driven hypertension management practice in the inpatient acute care setting. All patient demographic and clinical data were analyzed using descriptive statistics. Secondary safety outcomes included documented hypotensive events (SBP <90) and acute kidney injury (AKI, increase in SCr by 0.3 mg/dl within 48 hours). Results: During the study period, 26 referrals were placed, and 19 patients were included for review. On average, patients were on 2 anti-hypertensive medications prior to admission. From the time of referral to discharge (mean 6 days), systolic blood pressure (SBP) was reduced on average by 36 mmHg (mean percentage reduction 20%) and diastolic blood pressure (DBP) by 12 mmHg (mean percentage reduction 7%). Ten patients (53%) met the goal of SBP < 140 at discharge. There were 5 hypotensive events and 4 instances of AKI, all of which were mild and recovered prior to discharge. Conclusion: A pharmacist-managed hypertension CPA was successfully implemented in vascular neurology patients in the inpatient acute care setting. The practice demonstrated improved blood pressure control and minimal adverse outcomes.


2015 ◽  
Vol 103 (6) ◽  
Author(s):  
Hildegard Curtius ◽  
Gabriele Kaiser ◽  
Norman Lieck ◽  
Murat Güngör ◽  
Martina Klinkenberg ◽  
...  

AbstractThe impact of burn-up on the instant release fraction (IRF) from spent fuel was studied using very high burn-up UO


2018 ◽  
Vol 34 (2) ◽  
pp. 118-125 ◽  
Author(s):  
Jonathon Judkins ◽  
Irena Laska ◽  
Judith Paice ◽  
Priya Kumthekar

Purpose: The primary objective of this study was to quantify cancer family caregiver (FCG) quality of life (QOL) in a Southern Albanian population and to determine whether differences exist between 4 domains of QOL (physical, psychological, social, and spiritual). This study also sought to compare QOL in our cohort to QOL in historical studies that used the same survey instrument, and to examine correlations between demographic characteristics and QOL to identify any high-risk groups. Methods: A sample of 40 FCGs was recruited at the Mary Potter Palliative Care Clinic in Korçe, Albania. Each participant completed the City of Hope Quality of Life (Family Version), a validated 37-question instrument that measures caregiver well-being in 4 domains: physical, psychological, social, and spiritual well-being. Results: There were no significant differences between the composite scores of the 4 QOL domains in our study. However, there were differences when comparing self-reported QOL between domains (“Rate your overall physical/psychological/social/spiritual well-being”). The QOL measured in our study was significantly lower than in 3 studies from the United States that used the same questionnaire. There were no significant correlations between demographic groups and QOL. Conclusions: This study examines the impact that the paucity of palliative services has on the QOL of Albanian cancer FCGs. Although there were no domains of QOL or demographic groups identified in our study that were faring significantly worse than others, the poor overall QOL provides further evidence to support the continued development of palliative services for both patients and family members in Albania.


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