bluuebunny/crossref_metadata_2025 huggingface dataset:
Colon cancer cells secreted CXCL11 via RBP‐Jκ to facilitated tumour‐associated macrophage‐induced cancer metastasis
Authors: Liu Mengjie , Fu Xiao , Jiang Lili , Ma Jiequn , Zheng Xiaoqiang , Wang Shuhong , Guo Hui , Tian Tao , Nan Kejun , Wang Wenjuan
Published: October 2021

Metastasis is the main cause of colon cancer‐related deaths. RBP‐Jκ is involved in colon cancer development, but its function in colon cancer metastasis is still unclear. Tumour‐associated macrophages are the main cell components in tumour microenvironments. Here, we aimed to determine the function of RBP‐Jκ in colon cancer metastasis and its underlying mechanisms for modulating interactions between colon cancer cell and tumour‐associated macrophages. Through bioinformation analysis, we found that RBP‐Jκ was overexpressed in colon cancer tissues and associated with advanced colon cancer phenotypes, macrophage infiltration and shorter survival overall as confirmed by our patients’ data. And our patients’ data show that RBP‐Jκ expression and tumour‐associated macrophages infiltration are associated with colon cancer metastasis and are independent prognostic factors for colon cancer patients. Tumour‐associated macrophages induced colon cancer cell migration, invasion and epithelial‐mesenchymal transition through secreting TGF‐β1. Colon cancer cells with high RBP‐Jκ expression induced the expression of TGF‐β1 in tumour‐associated macrophages by secreting CXCL11. Our research revealed that colon cancer cells secreted CXCL11 via overexpression of RBP‐Jκ to enhance the expression of TGF‐β1 in tumour‐associated macrophages to further promote metastasis of colon cancer cells.
Evolution of seed mass associated with mating systems in multiple plant families
Authors: Tateyama Hirofumi , Chimura Kaori , Tsuchimatsu Takashi
Published: October 2021

In flowering plants, the evolution of self‐fertilization (selfing) from obligate outcrossing is regarded as one of the most prevalent evolutionary transitions. The evolution of selfing is often accompanied by various changes in genomic, physiological and morphological properties. In particular, a set of reproductive traits observed typically in selfing species is called the “selfing syndrome”. A mathematical model based on the kinship theory of genetic imprinting predicted that seed mass should become smaller in selfing species compared with outcrossing congeners, as a consequence of the reduced conflict between maternally and paternally derived alleles in selfing plants. Here, we test this prediction by examining the association between mating system and seed mass across a wide range of taxa (642 species), considering potential confounding factors: phylogenetic relationships and growth form. We focused on three plant families—Solanaceae, Brassicaceae and Asteraceae—where information on mating systems is abundant, and the analysis was performed for each family separately. When phylogenetic relationships were controlled, we consistently observed that selfers (represented by self‐compatible species) tended to have a smaller seed mass compared with outcrossers (represented by self‐incompatible species) in these families. In summary, our analysis suggests that small seeds should also be considered a hallmark of the selfing syndrome, although we note that mating systems have relatively small effects on seed mass variation.
Adsorption of PCE in alkali‐activated materials analysed by fluorescence microscopy
Authors: Wetzel Alexander , Link Janna , Middendorf Bernhard
Published: October 2021

The realisation of high‐performance concrete mixtures requires the use of superplasticizers to achieve a low water/binder ratio and thus high strengths. Polycarboxylate ethers (PCE) are mostly used as superplasticizers. The effectiveness of these superplasticizers depends on their chemical structure, the binders’ alkaline environment and the ions present in the pore solution of the binder. In high alkaline systems like some alkali‐activated materials no effective superplasticizer have been found yet. To unravel the compatibility of certain PCE to such a highly alkaline system a fluorescence microscopy approach was used. In first experiments, the adsorption of APEG (allyl ether) and MPEG (methacrylate) PCE on ground granulated blast furnace slag and fly ash was investigated varying the concentration of the activators. At a certain concentration, a complexation of the PCE can be recognised in fluorescence microscope. APEG shows a better stability compared to MPEG; this correlates with rheological investigations.
Hearing test results of newborns born from the coronavirus disease 2019 (COVID‐19) infected mothers: A tertiary center experience in Turkey
Authors: Yıldız Gazi , Kurt Didar , Mat Emre , Yıldız Pınar , Başol Gülfem , Gündogdu Elif Cansu , Kuru Betül , Topcu Bahtisen , Kale Ahmet
Published: October 2021

Objective

Congenital infections can cause newborn hearing loss. Although vertical transmission of coronavirus disease 2019 (COVID‐19) infection is theoretically possible, this has not been proven yet. To our knowledge, there is no previous report on whether COVID‐19 infection during pregnancy can cause congenital hearing loss. This paper aimed to find an answer to this question.

Method

This retrospective, single‐center study was performed between April 2020 and May 2021 at a tertiary care referral center in Turkey. A total of 422 pregnant women who had coronavirus infection during pregnancy were followed and 203 of them gave birth in our institution. Results of hearing screening tests of 199 newborns were assessed retrospectively.

Results

Of patients included in the study, 23 (11.6%) had the disease in the first trimester, 62 (31.2%) in the second trimester, and 114 (57.3%) in the third trimester. In the first hearing test performed on newborns, unilateral hearing loss was observed in 21 babies (10.5%). Hearing tests of these newborns were found to be normal in the second test performed 15 days later.

Conclusion

Considering the incidence of congenital hearing loss, the absence of hearing loss in our newborn population does not confirm the argument that coronavirus infection does not cause congenital hearing loss. This issue should be evaluated with larger patient series. In addition, it should be kept in mind that hearing loss can occur at later ages as well.
How Do People Disclose Their Mild‐To‐Moderate Hearing Loss?1,2
Authors: Katsuya Noriko , Sano Tomoko
Published: October 2021

This study used the Trajectory Equifinality Approach (TEA) to examine how people with acquired hearing loss and who are hard of hearing, without physical disability certificates, disclose their hearing loss. Eleven people with hearing loss participated in semi‐structured interviews. They talked about the process of their disclosure of their hearing loss from the time they became aware of it to the present. Participants who used not to actively disclose their hearing loss problem were divided into four types. These types were different in coping behaviors for hearing loss, perceptions of hearing‐loss problems, and the turning point (bifurcation point [BFP]) for the disclosure of hearing loss. The psychological support necessary for each type of person with hearing loss was discussed.
Terpene synthases in cucumber (Cucumis sativus) and their contribution to herbivore‐induced volatile terpenoid emission
Authors: He Jun , Verstappen Francel , Jiao Ao , Dicke Marcel , Bouwmeester Harro J. , Kappers Iris F.
Published: October 2021

Terpenoids play important roles in flavour, pollinator attraction and defence of plants. In cucumber (Cucumis sativus) they are important components of the herbivore‐induced plant volatile blend that attracts natural enemies of herbivores.

We annotated the cucumberTERPENE SYNTHASEgene (CsTPS) family and characterized their involvement in the response towards herbivores with different feeding guilds using a combined molecular and biochemical approach.

Transcripts of multipleCsTPSgenes were upregulated in leaves upon herbivory and the products generated by the expressed proteins match the terpenoids recorded in the volatile blend released by herbivore‐damaged leaves. Spatial and temporal analysis of the promoter activity ofCsTPSgenes showed that cell content‐feeding spider mites (Tetranychus urticae) and thrips (Frankliniella occidentalis) induced promoter activity ofCsTPS9andCsTPS19within hours after initiation of infestation, while phloem‐feeding aphids (Myzus persicae) inducedCsTPS2promoter activity.

Our findings offer detailed insights into the involvement of theTPSgene family in the dynamics and fine‐tuning of the emission of herbivore‐induced plant volatiles in cucumber, and open a new avenue to understand molecular mechanisms that affect plant–herbivore interactions.
Exogenous progesterone‐dependent modulation in the follicular dynamics of Bos indicus cattle undergoing repeated ovum pick‐up sessions
Authors: Nawaz Mudussar , Saleem Muhammad , Ullah Farid , Shabbir Khan Ghulam , Zahoor Imran , Ahmad Nasim , Riaz Amjad
Published: October 2021

The objective of the present study was to evaluate the role of serum progesterone (P4) in follicular dynamics, oocytes’ recovery and quality and their in vitro developmental competence during consecutive ovum pick‐up (OPU) sessions in Bos indicus dairy cows. Wave‐synchronized Sahiwal cattle (n = 20) were randomly divided into treatment (n = 10) and control (n = 10) groups. CIDR was used as a source of external progesterone in the treatment group. Four consecutive OPU sessions at 96‐hr intervals were conducted and repeated ultrasonography at 12‐hr intervals was done to monitor follicular dynamics. The viable oocytes were processed for IVC following IVM and IVF until day 7. The serum P4 concentrations in the P4 and control groups were recorded as 2.31 ± 0.059 versus.0.32 ± 0.065 ng/ml, respectively (p < .05). In the treatment group, the total number of recorded follicles was higher (p < .05; 12.05 ± 0.37 versus. 10.87 ± 0.40), whilst the growth rate (mm/day) of follicles was lower (p > .05). Per session recovered oocytes (5.31 ± 0.19 versus. 3.58 ± 0.21; p < .0001) and recovery rate (54.23 versus. 42.53%; p < .05) were also higher in the treatment group compared to control. Similarly, the viable oocytes (4.54 ± 0.187 versus. 3.06 ± 0.199) and the number of grade I and II oocytes per session (3.37 ± 0.196 versus. 2.06 ± 0.21) were higher (p < .05) in the treatment group compared with the control group. However, the nuclear maturation, cleavage, and blastocyst rate did not differ (p > .05) between the groups. Taken together, during OPU sessions, serum P4 improves oocytes’ recovery and quality, whilst does not affect the in vitro developmental competence of recovered oocytes.
Factors influencing seed mix design for prairie restoration
Authors: Barak Rebecca S. , Ma Zhao , Brudvig Lars A. , Havens Kayri
Published: October 2021

Decision‐making is central to restoration practice, from the framing of objectives to the employment of tools and strategies. Yet, it remains largely unclear how decisions are made during restoration and this limits understanding of how restoration managers design and implement restoration projects and what restoration approaches may be most effective. This is true for tallgrass prairies in the Midwestern United States, which are commonly restored through seed sowing. To understand how managers make decisions during prairie restoration, we used a mixed‐methods approach including interviews, a focus group, and an online survey, to ask managers about: restoration objectives, factors influencing seed mix design, tools and resources used in seed mix design, seeding methods, and monitoring. Respondents considered biodiversity the most important restoration objective, and the most important biodiversity measures were species richness and functional group diversity. Seed mix design was influenced by seed availability. We identified 141 taxa that managers would like to use in restoration, but cannot due to factors like cost, availability, or problems with germination or establishment. Managers most frequently used their own experience and consultation with other practitioners to guide seed mix design; and commonly used tools developed within their organization. Most managers agreed that monitoring was important for assessing restoration outcomes, but were unable to devote enough time to monitoring. These findings illustrate opportunities for partnerships, among restoration managers, and among managers, seed producers, and researchers.
Is Crisis and Emergency Risk Communication as Effective as Vaccination for Preventing Virus Diffusion? Measuring the Impacts of Failure in CERC with MERS‐CoV Outbreak in South Korea
Authors: Yoon Ho Young
Published: October 2021

This study measured the impacts of failure in Crisis and Emergency Risk Communication (CERC) during the outbreak of a contagious Corona viral disease. The study measured the impacts by the number of individuals and hospitals exposed to the virus. The 2015 Middle East Respiratory Syndrome (MERS) outbreak in South Korea was used to investigate the consequences of CERC failure, where the names of hospitals exposed to MERS‐CoV were withheld from the public during the early stage of virus diffusion. Empirical data analyses and simulated model tests were conducted. The findings of analyses and tests show that an early announcement of the hospital names and publicizing the necessary preventive measures could have reduced the rate of infection by approximately 85% and the number of contaminated healthcare facilities by 39% at maximum. This level of reduction is comparable to that of vaccination and of social distancing.
Korean Relative Clauses: Metonymy, Zone Activation, and Reference Point*
Authors: Park Chongwon
Published: October 2021

This article develops an analysis of three types of Korean Relative Clauses (RCs) from a Cognitive Grammar perspective. The three types under examination are the Internally Headed RC Construction (IHRCC), the Externally Headed RC Construction (EHRCC), and the Double RC Construction (DRCC) which is a subtype of the EHRCC. It is demonstrated that the notion of metonymy helps us properly tease out the nature and provide a uniform account of the hitherto neglected Korean RC constructions. The “mismatch” observed between the syntactic object and the semantic head in the IHRCC is nothing but a case of the active‐zone/profile discrepancy. The putative island constraint or subjacency violations in the EHRC and the DRCC are not an issue because the head nominals in those examples are associated with reference points that are exocentrically‐created and thus exist outside of the inner RCs.
In vitro compatibility testing of canine and rabbit blood
Authors: Cutler Simone M. , Richardson Jenna , Eatwell Kevin , Llewellyn Efa A.
Published: October 2021

Objective

To determine the in vitro compatibility of rabbit and canine blood using both a tube and slide agglutination crossmatch technique and to compare the results obtained from these 2 methods.

Design

Prospective observational laboratory study from January to March 2020.

Setting

University veterinary teaching hospital.

Animals

Six client‐owned rabbits ≥3.5 kg undergoing phlebotomy for a clinical reason. “Pigtail” blood samples from 3 dog erythrocyte antigen (DEA) 1‐positive and 3 DEA 1‐negative canine packed red blood cell units.

Interventions

Blood from each rabbit was crossmatched with a single unit of canine blood using both a standard laboratory tube agglutination technique and a simple slide agglutination method with each rabbit/canine unit serving as its own intraassay control. Tube crossmatches were evaluated for agglutination both macro‐ and microscopically and assessed for hemolysis. Slide crossmatches were assessed for the presence of agglutination both macro‐ and microscopically. 

Measurements and Main Results

All crossmatches were incompatible. Varying degrees of agglutination were seen for all crossmatches. Hemolysis was observed with all minor tube crossmatches. Results of both crossmatch techniques were in close agreement. 

Conclusions

The crossmatch results in this present study strongly demonstrate in vitro incompatibility between canine and rabbit blood. Agreement between the 2 techniques in this study indicates that the slide agglutination technique may be quicker, require less blood, and provide reliable results in exclusively assessing the compatibility of canine and rabbit blood. Based on the results of this study, emergency xenotransfusion of canine blood to rabbits cannot be recommended.
Espacio urbano periférico y la construcción social del riesgo en ciudades intermedias
Authors: Narváez Quiñonez Iván Tarcicio , Durán Saavedra Gustavo Adolfo , Menoscal Cevallos Jonathan Javier , Bayón Jiménez Manuel
Published: October 2021

La expansión urbana en Latinoamérica es un fenómeno que se ha hecho más visible durante las últimas décadas; en Ecuador, se ha materializado con la generación de nuevas ciudades intermedias, a lo largo de ejes antes inexistentes. Este crecimiento está relacionado con el asentamiento de nuevos barrios sobre áreas amenazadas. Lo expuesto ha dado lugar al cuestionamiento de los métodos de medición del riesgo y su naturalización, y al desarrollo de una propuesta teórico-metodológica que coadyuva a problematizar y complejizar la construcción social del riesgo. En el caso de la Costa ecuatoriana, la existencia de ciudades intermedias con nuevos asentamientos en áreas amenazadas es común. En la presente investigación, a través del estudio de los barrios Cruz María y Rosa María 2, de las ciudades de Quevedo y de Milagro, respectivamente, se desarrolla una metodología de análisis de la construcción social del riesgo, que se proyecta para el nuevo eje urbano interno costero de Ecuador
Imprinted Glass Fiber-Reinforced Polymer Vascular Networks for Creating Self-Healing Wind Turbine Blades
Authors: Amano Ryoichi S. , Lewinski Giovanni , Shen Rulin
Published: October 2021

Self-healing wind turbine blades can reduce costs associated with maintenance, repair, and energy compensation. Self-healing is the ability to sustain and recover from damage autonomously. We discuss the efforts made to optimize the self-healing properties of wind turbine blades and provide a new system to maximize this offset. This system utilizes vacuum-assisted resin transfer molding (VARTM), and 3D printed templates to imprint a vascular network onto a single glass fiber-reinforced polymer (FRP) sheet. This imprinted layer is infused with Grubbs first-generation catalyst and filled with dicyclopentadiene (DCPD) which is then sealed using plastic sheeting. The sealed imprint layer is embedded into a larger multilayer FRP prior to VARTM. After VARTM, the completed multilayer FRP is fully capable of self-healing microcracks. Three-dimensional printed templates with square grid and hexagonal patterns were used to evaluate how differences in DCPD distribution affect overall recovery. Three-point bending tests were performed to obtain the maximum flexural strengths of the FRP samples before and after self-healing to evaluate recovery. Overall, with the imprint layer method, the catalyst was focused in one area of the complete FRP, reducing the amount of unused catalyst present in the FRP. Also, the samples created using the imprint method were able to achieve a maximum average recovery of over 200% and a storage efficiency of 100%.
Singular and Nonsingular Kernels Aspect of Time-Fractional Coupled Spring-Mass System
Authors: Jena Rajarama Mohan , Chakraverty Snehashish
Published: October 2021

Dynamical behaviors of the time-fractional nonlinear model of the coupled spring-mass system with damping have been explored here. Fractional derivatives with singular and nonsingular kernels are used to assess the suggested model. The fractional Adams–Bashforth numerical method based on Lagrange polynomial interpolation is applied to solve the system with nonlocal operators. Existence, Ulam–Hyers stability, and uniqueness of the solution are established by using fixed-point theory and nonlinear analysis. Further, the error analysis of the present method has also been included. Finally, the behavior of the solution is explained by graphical representations through numerical simulations.
Scenario Development for Nuclear Emergency Decision Deduction Training Platform for Radiographers in Developing Countries (Case Study, Ghana)
Authors: Oforiwaa Priscilla Obeng , Manchun Liang , Chao Zhang , Guofeng Su , Ke Li
Published: October 2021

Nuclear Radiological accident is of great threat to the Nuclear Agency aside nuclear terrorism. In countries with little or no major nuclear infrastructural facilities, it is of great importance to educate stakeholders and employees in the handling and emergency decision involved in the usage of these radionuclides, thus training on this platform gives the maximum and technical know-how in cases where it is difficult to procure types of equipment needed for such educational exercise in real life. Ghana is a country that seeks to increase the use of nuclear technological applications. Sealed Radioactive Sources are used in Ghana for research, Agriculture, mining exploration and brachytherapy. Operators need to train immensely in the handling of these sources.

The NEDDTP is a software system to help conduct training and emergency exercises simulation. The NEDDTP is developed by the China Nuclear Security center of excellence with the aim of performing the simulation and training of radiographers and emergency workers in the nuclear industry. This training platform gives a 3D real-life training scenarios, emergency simulation, command and dispatch, Process record and evaluation in exercise with virtual reality display for radiological worker. This paper elaborates on the process for scenario design, types of scenario development for different types of radiological accidents and the stages involved in training with these scenarios.
System Modelling Approach of Radionuclide Soil-to-Plant Transfer for Nuclear Emergencies Decision; Case Study - China
Authors: Oforiwaa Priscilla Obeng , Manchun Liang , Guofeng Su
Published: October 2021

Nuclear Energy Development is gradually gaining root in the energy mix of the Chinese society. It is quite evident to develop all possible emergency evaluation situation in the event of nuclear energy. Nuclear Emergency falls under the relative serious emergency incident grades according to the degree of social harm done and the extent of repercussions and other factors.

This paper illustrates system modelling predictions of the transfer of radiocesium from soil-to-plant during nuclear emergency. Planned discharges of radionuclides are passed by mathematical models that can be used as tools to evaluate the effective ways of countermeasure actions in an event of an emergency.

The empirical approach often associates with considerably uncertainty due to the large variability in the transfer factor The mechanistic approach also presents complexities and a large amount of specific parameters makes this approach impractical for nuclear emergency preparedness and response purposes.

The semi-mechanistic approach factorizes more soil and plant parameters than the empirical approach. Therefore, it is applicable to a wider range of environmental conditions. The nuclear emergency adapts the parameterization of the Absalom model which is sufficiently robust and practical, hence fit more for the purpose of planning and responding to nuclear emergencies as compared to the empirical and mechanistic approaches.
Numerical Evaluation of Sodium-Water Reaction Based on Engineering Approach With Particle Method
Authors: Kosaka Wataru , Uchibori Akihiro , Yanagisawa Hideki , Takata Takashi , Jang Sunghyon
Published: October 2021

For safety assessment or design of a steam generator (SG) of a sodium-cooled fast reactor, it is important to evaluate the effects of a multiphase flow involving sodium-water reaction. If pressurized water/water-vapor leaks from a tube, it forms a corrosive, high-temperature, and high-velocity jet, and may cause failure of the adjacent tubes. The occurrence of tube failure on many tubes will lead to failure of the boundary between the primary and secondary cooling loops.

The numerical analysis code, LEAP-III, has been developed to evaluate water leak rate considering the effects of the above-mentioned phenomena with short computational time. In some cases, however, the current LEAP-III provides excessive conservativeness due to its temperature distribution evaluation model.

In order to reduce this excess, we have developed a new Lagrange particle method with several engineering approaches. We also performed test analyses which simulate time development of the vapor jet with chemical reaction in a SG. The results of the developed method were compared with ones of the multi-dimensional multiphase thermal hydraulic analysis code, SERAPHIM which considers compressibility and chemical reaction. Through the test analyses, the basic capability of the developed method was confirmed.
Experimental Study on Bubble and Aerosol Behavior During Pool Scrubbing
Authors: Yoshida Kohei , Fujiwara Kota , Kaneko Akiko , Abe Yutaka
Published: October 2021

Understanding radioactive aerosol behavior is important during severe accidents in nuclear power plants. In particular, pool scrubbing at a suppression pool is a key factor for estimating the leakage of radioactive aerosol into the environment. Therefore, we have to elucidate the mechanism of the aerosol transfer from the gas phase to the liquid phase during bubbly flow. Currently, models to evaluate the amount of aerosol removal by pool scrubbing have been incorporated into integrated severe accident analysis codes such as MELCOR. However, the models for bubbles and aerosols behavior have not been validated enough by experiment. Therefore, the measurement of bubbles and aerosols behavior is required for validation and reconstruction pool scrubbing model. However, the quantitative measurement of bubbly flow is very difficult by complicated bubble shape and overlapping of bubbles in visualization. The wire-mesh sensor (WMS) is one of the most effective measuring methods for complicated bubbly flow. The reconstruction method of bubbly flow by WMS measurement is suggested by Prasser et al. This method can measure the bubble surface, meanwhile, individual bubble velocity and volume are not one-to-one correspondence because bubble volume is calculated by using radial average velocity. Kanai et al. proposed a method for acquisition bubble three-dimensional velocity method by bubble tracking. In this method, bubble velocity and volume are one-to-one correspondence. Thus, we suggested an algorithm of bubble surface measurement by applying a bubble tracking method. The bubble three-dimensional velocity and surface area is obtained by this algorithm. As a result, bubble rising velocity in bubbly flow is higher than bubble terminal velocity according to causing liquid phase velocity. In addition, the gas-liquid total interfacial area is overestimated in MELCOR predict by overestimating bubble breakup. This result suggests that the overestimating of DF at downstream is caused by overestimating bubble breakup in MELCOR model.
Microscopic Heat Transfer Characteristics During Cooling of High Temperature Surface by a Falling Liquid Film
Authors: Umehara Yutaro , Okawa Tomio
Published: October 2021

When the dry region on the high-temperature wall is cooled down by liquid, the dry region is transformed into wet region as the temperature shifts in a short time. Vigorous boiling occurs during the temperature transition. Especially, it is called the rewetting phenomenon that liquid contacts dry region on the high-temperature wall in the first time. In nuclear plants, it is essential for nuclear power plant safety to understand this phenomenon. Under severe accidents, a liquid film formed by an emergency core cooling system (ECCS) removes the decay heat of fuel rods. To determine the start time of ECCS, the time required for the liquid film to cover the fuel rods needs to be clarified. Working time is calculated by using rewetting velocity which means the boundary movement speed between liquid and dry region. Previous research reported rewetting velocity was calculated by heat conduction equation using the boundary condition (= heat transfer coefficient (HTC) distribution). However, proposed HTC distributions were not defined directly from experimental data but defined to match experimental results. This is because the temperature was measured by thermocouples which were not enough to obtain temperature distribution. In this study, two kinds of experiments were done to define HTC distribution from experimental results and to elucidate the rewetting phenomenon. First, as liquid film fell along high temperature wall, the transition of temperature distribution of the wall was measured by an infrared camera. Copper plate was used to heat transfer surface. From the results of temperature distribution, HTC distribution was calculated. And then, four critical parameters that consisted of HTC distribution were investigated against experimental parameters.

Second, a similar experiment was conducted using silicon wafer which is transparent for infrared rays as the heat transfer surface to observe the rewetting phenomenon, especially the precursory cooling region. The precursory cooling region is considered as one of the important regions to calculate exact rewetting velocity. An infrared camera and high speed camera was used in this experiment. An infrared camera took temperature distribution from the backside which is the opposite side of the liquid film. A high-speed camera took liquid film condition from the front side. Since both cameras were synchronized, this experimental apparatus was able to observe both HTC distribution and liquid film condition at the same time. As a result of observation, the precursory cooling region is the area where drying and wetting are repeated by boiling.
Outline of Guideline for Seismic Response Analysis Method Using 3D Finite Element Model of Reactor Building
Authors: Choi Byunghyun , Nishida Akemi , Shiomi Tadahiko , Kawata Manabu , Li Yinsheng
Published: October 2021

In the seismic safety assessment and design of building structures in nuclear facilities, lumped mass models are conventionally used. However, they cannot possess the required high-accuracy evaluation of nuclear facilities, such as the local response at the equipment location in a reactor building. From this point of view, a seismic response analysis method using a three-dimensional finite element (3D FE) model is indispensable. Furthermore, because analysis results obtained using 3D FE models vary to a large degree depending on the experience and knowledge of analysts, the quality of analysis results should be ensured by developing a standard analysis method. In the Japan Atomic Energy Agency, we have developed a guideline for seismic response analysis methods that adopt 3D FE models of reactor buildings, and we plan to publish it as JAEA report. The guideline consists of a main body, commentary, and several appendixes; it also includes procedures, recommendations, points of attention, and a technical basis for conducting seismic response analysis using 3D FE models of reactor buildings. In this paper, the outline of the guideline and analysis examples based on the guideline are presented.
Research on Eccentricity Performance of Capacitance Rod Position Measurement Sensor for Measuring Non-Metallic Rod
Authors: Li Yanlin , Qin Benke , Bo Hanliang
Published: October 2021

Rod position measurement sensor is the key equipment of control rod hydraulic drive line, the measurement accuracy of the sensor is directly related to the safety and reliability of the reactor. Capacitance rod position measurement sensor is generally composed of excitation and detection electrodes, ceramic tube, outer shielding layer and measuring rod. For the double helix capacitance rod position measurement sensor with non-metallic measuring rod, the static characteristic experiment of the sensor was completed, the finite element method was used to establish the calculation model and the model was verified by the experimental results. By the calculation model, the influence of electrode angle, pitch, thickness and relative permittivity of ceramic tube on the eccentricity error of the sensor was systematically analyzed, the optimal combination of design parameters were obtained by orthogonal test method. The results show that the calculation results are in good agreement with the experimental results, the eccentricity error can be reduced by reducing the electrode angle, increasing the electrode pitch, increasing the thickness and reducing the relative permittivity of the ceramic tube. The design scheme of the sensor obtained by the orthogonal test can greatly reduce the eccentricity error and realize the requirement of rod position measurement without losing step. The research results provide guidance for the design and optimization of capacitance rod position measurement sensor.
A New Concept for Irradiation Experiments in Fast-Reactor Environment: CFD Simulation of the LBE Loop in HYST
Authors: Kong Ran , Kim Seungjin , Wahlen Robert , Grimm Terry
Published: October 2021

The current work investigates the thermal-hydraulics of the fast core of a HYbrid fast/thermal core configuration Subcritical Testbed (HYST), a new concept for irradiation experiments in fast-reactor-like environment. The Reynolds-Averaged Navier Stokes (RANS) simulations using ANSYS Fluent are performed. A benchmark study is first performed to validate the simulation of liquid LBE flow in a wire-wrapped rod bundle geometry using the experimental data in Pacio et al. (2016), which provides the most detailed data for rod surface temperature, LBE temperature in the subchannel, and pressure drop along the test section. Two turbulence models (Standard k-ε model with Standard Wall Function and Realizable k-ε model with Enhanced Wall Treatment), two approaches to simplify the wire-rod contact and different models for turbulent Prandtl number (Prt) are tested. It is found that the selected models can predict the data well and are therefore used for simulations of the LBE loop in HYST. A mesh independence study is performed in simulating the LBE loop in HYST with three different meshes being generated (number of cells: 14.8 million, 25.8 million, and 45.4 million). It is found that the mesh independency is reached using the mesh with 25.8 million cells. The effect of non-uniform power distribution in the radial direction of the core is investigated. It is found that the temperature profiles change significantly when uniform power distribution changes to non-uniform. An experimental facility is being constructed and newly collected data will be used to evaluate the RANS simulations. Once validated, the current model will be valuable for the design, licensing, and operation of the HYST prototype.
Study on Heat Transfer Coefficient of Supercritical Water Based on Factorial Analysis
Authors: Xu Peng , Zhou Tao , Chen Ning , Chen Juan , Fu Zhongguan
Published: October 2021

Heat transfer coefficient has an important influence on the flow and heat transfer of supercritical water in the core channels. The effects of different factors and their interactions on the heat transfer coefficient of the supercritical water were studied by full factorial experimental design method, such as pressure, mass flow rate, heat flux, and inlet temperature. The results show that: Within the range of the tested working conditions, effect D (inlet temperature), effect B (mass flow rate) and effect A (pressure) had a significant impact on the heat transfer coefficient, where the percentage contribution of effect D was 48.21%; effect B was 21.58%; effect A was 15.1%. The percentage contribution of other factors and their interactions on the heat transfer coefficient of the supercritical water can be ignored. At the same time, a prediction formula of heat transfer coefficient on supercritical water was fitted, and it was found that the prediction error of this formula conformed to the assumption of normality, and the prediction error was 10.5%.
Risk Factors Selection Approach for Nuclear Decommissioning Risk Assessment, Modeling, and Management
Authors: Junior Awodi Ngbede , Liu Yong-Kuo , Ayodeji Abiodun , Adibeli Justina Onyinyechukwu
Published: October 2021

Due to the complexity of nuclear decommissioning projects, developing a risk assessment model to manage the project risk is paramount. The current study is an attempt to identify all the possible risk factors that can arise in a nuclear decommissioning project. A literature review and the expert judgement method were used to identify and analyse all the possible risk factors. The identified factors are then further refined, and the most important risk factors are selected to be included in the final risk assessment model. This work presents the criteria developed for the simplification, refinement, and assessment of risk factors. The criteria used considered the availability of data, the clarity, and the measurability of the selected factors. Risk factors with a lower rating are eliminated, and those with a similar focus of attention are grouped, enabling the selection of a simplified final list of risk factors for the model. This work also proposed a method of assessment for the remaining factors to allow the quantification of individual risk factors within the model. From the 81 risk factors initially identified, 18 consolidated factors are considered for the development of the risk assessment model. The selection process and risk rating approach presented in this work serves as a critical foundation for the development of a robust nuclear decommissioning risk assessment and management.
Study on Eutectic Melting Behavior of Control Rod Materials in Core Disruptive Accidents of Sodium-Cooled Fast Reactors: (1) Project Overview and Progress Until 2019
Authors: Yamano Hidemasa , Takai Toshihide , Furukawa Tomohiro , Kikuchi Shin , Emura Yuki , Kamiyama Kenji , Fukuyama Hiroyuki , Higashi Hideo , Nishi Tsuyoshi , Ohta Hiromichi , Morita Koji , Nakamura Kinya
Published: October 2021

One of the key issues in a core disruptive accident (CDA) evaluation in sodium-cooled fast reactors is eutectic reactions between boron carbide (B4C) and stainless steel (SS) as well as its relocation. Such behaviors have never been simulated in CDA numerical analyses in the past, therefore it is necessary to develop a physical model and incorporate the model into the CDA analysis code. This study focuses on B4C-SS eutectic melting experiments, thermophysical property measurement of the eutectic melt, and physical model development for the eutectic melting reaction. The eutectic experiments involve the visualization experiments, eutectic reaction rate experiments and material analyses. The thermophysical properties are measured in a range from solid to liquid state. The physical model is developed for a CDA computer code based on the measured data of the eutectic reaction rate and the physical properties. This paper describes the project overview and progress of experimental and analytical studies conducted until 2019. Specific results in this paper are the validation of physical model describing B4C-SS eutectic reaction in the CDA analysis code, SIMMER-III, through the numerical analysis of the B4C-SS eutectic melting experiments in which a B4C block was placed in a SS pool.
Nanoindentation Test of F321 Austenitic Stainless Steel Under Fe-ion Irradiation
Authors: Liu Meidan , Nie Junfeng , Lin Pandong
Published: October 2021

Nuclear technology, as a high quality, clean and reliable energy supply, is attracting broad interest from countries across the world. F321 austenitic stainless steel (F321SS) is widely utilized in key components of nuclear power plant due to its excellent corrosion resistance and high temperature mechanical properties. Irradiation can easily lead to the degradation behaviors of materials, such as irradiation hardening, irradiation embrittlement and high-temperature He embrittlement, etc. Understanding such degradation is important for predicting the evolution of material behavior under irradiation and extending the lifespan of existing nuclear reactors. Ion irradiation is most commonly used to model neutron-induced damage since the irradiation conditions (temperature, flux, spectrum, etc.) can be regulated more accurately and flexibly. In this paper, the Fe-ion irradiation experiments of F321SS at different temperatures and doses were carried out, and the nanoindentation experiments under different conditions were further conducted. Irradiation hardening is observed in all specimens and strongly depending on irradiation temperature and damage dose. The hardness after irradiating increases with doses and saturates for at least 1dpa under low temperature regimes (< 300°C). However, at higher temperature (450°C and 560°C), nano-hardness reaches the peak at ∼0.5dpa and then declines. Moreover, the hardness of all specimens has a similar trend with temperature, that is, it first increases, reaches the peak, and then decreases.
Numerical Simulation of Vortex Shedding Downstream of a Thermoacoustic Engine Stack
Authors: Qiao Bowen , Yamada Shota , Tanaka Gaku
Published: October 2021

Thermoacoustic engines use waste heat available at a higher temperature to produce mechanical energy in the form of waves. The purpose of this study is to visualize the fluid behavior downstream of the stack of a thermoacoustic engine by applying numerical analysis and to explore the effect of vortex shedding on the temperature field. The self-sustained oscillation is reproduced by two-dimensional numerical analysis using the compressible solver of OpenFOAM, and the vorticity field and temperature field were visualized. The vortex downstream of the stack changed from symmetric to asymmetric near the peak of the flow velocity. Changes in the vortex structure by the unsteady flow caused irregular and non-uniform temperature field. It is found that the vortex significantly affects the heat transfer between the heat exchanger and the fluid.
Measurement of Liquid Film Thickness for Annular Two-Phase HFC134a Gas-Liquid Ethanol Flow in the Vertical Tube
Authors: Zhang Huacheng , Hisano Tutomo , Mori Shoji , Yoshida Hiroyuki
Published: October 2021

Annular gas-liquid two-phase flows, such as the flows attached to the fuel rods of boiling water reactors (BWR), are a prevalent occurrence in industrial processes. At the gas-liquid interface of such flows, disturbance waves with diverse velocity and amplitude commonly arise. Since the thin liquid film between two successive disturbance waves leads to the dryout on the heating surface and limits the performance of the BWRs, complete knowledge of the disturbance waves is of great importance for the characterized properties of disturbance waves. The properties of disturbance waves have been studied by numerous researchers through extensive experimental and analytical approaches. However, most of the experimental data and analyses available in the literature are limited to the near atmospheric condition. In consideration of the properties of liquids and gases under atmospheric pressure which are distinct from those under BWR operating conditions (7 MPa, 285 °C), we employed the HFC134a gas and liquid ethanol whose properties at relatively low pressure and temperature (0.7 MPa, 40 °C) are similar to those of steam and water under BWR operating conditions as working fluids in a tubular test section having an inside diameter 5.0mm. Meanwhile, the liquid film thickness is measured by conductance probes. In this study, we report the liquid film thickness characteristics in a two-phase HFC134a gas-liquid ethanol flow. A simple model of the height of a disturbance wave was also proposed.
Preliminary Simulations on the Atmospheric Dispersion of Radioactive Substance for the Two Sites in Tunisia
Authors: Ghannouchi Elyes , Wang Yu , Cao Jianzhu , Xie Feng , Zhang Liguo , Tong Jiejuan , Yao Rentai , Debbabi Khaled
Published: October 2021

Global climate change, record-high oil prices and the deceasing availability of fossil fuels are forcing us to rethink the way we deal with our energy needs. In response to this growing concern, and as an indication of the seriousness of these issues, the current administration of Tunisia is executing strategic plans to increase green energy sources. Nuclear energy is one such alternative source. The evaluation of the transport in the atmosphere of radioactive substance discharged from a nuclear power plant under normal operational or accidental conditions is a requirement of design and licensing. The atmosphere is a major exposure pathway by which radioactive materials that are either routinely discharged under authorization or accidentally released from a nuclear power plant could be dispersed in the environment and transported to locations where they may reach the public. In this paper, the development plan for nuclear energy in Tunisia will be introduced, and the atmospheric dispersion model of radioactive substance for the two sites in Tunisia will be presented. The meteorological parameters for specific site will be illustrated with the evaluation of the meteorological investigation. Contamination in the air and on the ground over short and long time periods will be described in the atmospheric dispersion models. Several related issues will be discussed, including the suitability of the meteorological investigation, appropriateness of the dispersion models, etc.
Grey Correlation Study on Natural Circulation Heat Transfer Coefficient of Liquid Metal
Authors: Ning Chen , Tao Zhou , Lanyu Zhou , Tian Qi , Juan Chen , Xiang Feng
Published: October 2021

Liquid metals have excellent thermal, nuclear physics, and high-density power properties that allow them to efficiently take heat out of the reactor. Based on the data of Natrium, Natrium-Kalium, Plumbum and Plumbum-Bismuth simulated by CFX software, the three factors of heating power, system pressure and inlet temperature were selected, and the analysis method of grey correlation model was used to analyze the correlation degree and weight of these factors to the heat transfer coefficient of different liquid metals. Through analysis, it can be concluded that: under Natrium, Plumbum and Plumbum-Bismuth working medium, the correlation degree and weight importance of heating power to heat transfer coefficient are greater than that of system pressure, while under NatriumKalium working medium, the correlation degree and weight of system pressure and heating power to heat transfer coefficient are roughly equal; The inlet temperature has the greatest correlation to the heat transfer coefficients of the four liquid metals, and the inlet temperature contributes the largest weight to the change in the heat transfer coefficient, that is, the inlet temperature and the heat transfer coefficient are most closely related; When the resolution is 0.01, the correlation degree ofthe heat transfer coefficient can be clearly distinguished between these three factors. Through the analysis of the degree of correlation and the weight of the influencing factors of different liquid metal heat transfer coefficients, it is helpful to discover the unstable factors that cause the deterioration of liquid metal heat transfer, and it is of great significance to the choice of new reactor coolants.