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The physics of Radio-Frequency (RF) wave heating in the Ion Cyclotron Range of Frequencies (ICRF) in the core plasmas of fusion devices are relatively well understood while those in the Scrape-Off Layer (SOL) remain still unresolved. This paper is dedicated to study the ICRF interactions with the plasma edge, mainly from the theoretical and numerical point of view, in particular with the 3D edge plasma fluid and neutral transport code EMC3-EIRENE and various wave codes. Here emphasis is given to the improvement of ICRF coupling with local gas puffing and to the ICRF induced density convection in the SOL.

The recent scientific research on ASDEX Upgrade (AUG) has greatly advanced solutions to two issues of Radio Frequency (RF) heating in the Ion Cyclotron Range of Frequencies (ICRF): (a) the coupling of ICRF power to the plasma is significantly improved by density tailoring with local gas puffing; (b) the release of RF-specific impurities is significantly reduced by minimizing the RF near field with 3-strap antennas. This paper summarizes the applied methods and reviews the associated achievements.

The power depositions on EAST upgraded divertor plates effected by impurity injection positions are studied numerically by the 3D edge transport code EMC3-EIRENE. It is found that the toroidal widening of the non-axisymmetric heat fluxes reaches a maximum though differing for the individual radial injection positions of carbon (methane), nitrogen and neon. Line average of friction force and ion thermal gradient force along the magnetic field lines has been calculated to reveal the correlation between the non-axisymmetric heat loads on the target plates and the distributions of the radiation power density. The results illustrate that when impurities are injected away from the separatrix with the high scrape-off layer input power, the radiation power density is locally low but the total radiation power is significant. The reason is that the toroidal-symmetry-breaking distribution of electron temperature gives rise to the expanding diffusion of impurity density and radiation power density, which reduces the heat flux deposited on the divertor plates.

In magnetically confined tokamak plasmas the width of plasma Scrape-off Layer (SOL) allows direct estimation of anomalous diffusivity in limited and diverted versions of plasma configurations. The diffusivity coupled to edge and SOL plasma fluctuations is to be a decisive factor in stability of fusion grade plasmas and can be characterized for its dependence on 3D effects in moderate size tokamaks like Aditya. For Aditya tokamak configuration, 3D effects in SOL plasma transport are studied using 3D Monte-Carlo transport code combination EMC3-EIRENE to complement the limited probe measurements during experimental operation of the device. As an important 3D effects, variation from 1D estimates of up and downstream density scale lengths are recovered to generate appropriate corrections for estimates of plasma diffusivity and other transport propertied measured in Aditya tokamak plasma.

This paper analyzes the neutral fluxes in the divertor region of the W7-X standard configuration for different input powers, both under attached and detached conditions. The performed analysis is conducted through EMC3-EIRENE simulations. They show the importance of the horizontal divertor to generate neutrals, and resolve the neutral plugging in the divertor region. Simulations of detached cases show a decrease in the number of generated neutrals compared to the attached simulations, in addition to a higher fraction of the ion flux arriving on the baffles during detachment. As the ionization takes place further inside the plasma during detachment, a larger percentage of the generated neutral particles leave the divertor as neutrals. The leakage in the poloidal and toroidal direction increases, just as the fraction of collected particles at the pumping gap. The fraction of pumped particles increases with a factor two, but stays below one percent. This demonstrates that detachment with the current target geometry, although it improves the power exhaust, is not yet leading to an increased particle exhaust.

An integrated modeling framework for investigating the application of solid boron powder injection for real-time surface conditioning of plasma-facing components in tokamak environments is presented. Utilizing the DIII-D impurity powder dropper setup, this study simulates B powder injection scenarios ranging from mg/s to tens of mg/s, corresponding to B flux rates of \\(10^{20}-10^{21}\\) B/s in standard L-mode conditions. The comprehensive modeling approach combines EMC3-EIRENE for simulating the D plasma background and DIS for the ablation and transport of the B powder particles. The results show substantial transport of B to the inboard lower divertor, predominantly influenced by the main ion plasma flow. The dependency on powder particle size (5-250 \\(\\mu\\)m) was found to be insignificant for the scenario considered. The effects of erosion and redeposition were considered to reconcile the discrepancies with experimental observations, which saw substantial deposition on the outer divertor PFCs. For this purpose, the WallDYN3D code was updated to include B sources within the plasma domain and integrated into the modeling framework. The mixed-material migration modeling shows evolving B deposition patterns, suggesting the formation of mixed B-C layers or predominantly B coverage depending on the powder mass flow rate. While the modeling outcomes at lower B injection rates tend to align with experimental observations, the prediction of near-pure B layers at higher rates has yet to be experimentally verified in the C environment of the DIII-D tokamak. The extensive reach of B layers found in the modeling suggests the need for modeling that encompasses the entire wall geometry for more accurate experimental correlations. This integrated approach sets a precedent for analyzing and applying real-time in-situ boron coating techniques in advanced tokamak scenarios, potentially extendable to ITER.

Reduction of particle and heat fluxes to plasma facing components is critical to achieve stable conditions for both the plasma and the plasma material interface in magnetic confinement fusion experiments. A stable and reproducible plasma state in which the heat flux is almost completely removed from the material surfaces was discovered recently in the Wendelstein 7-X stellarator experiment. At the same time also particle fluxes are reduced such that material erosion can be mitigated. Sufficient neutral pressure was reached to maintain stable particle exhaust for density control in this plasma state. This regime could be maintained for up to 28 seconds with a minimum feedback control.

The microstructures of gypsum board and gypsum particleboard were observed by SEM. The effects of retarder and waterproof agent on the shape and the average dimension of the gypsum crystal were discussed. The mechanism was investigated as well. Four typical instances, i e, the gypsum crystal shape, the gypsum combined with particles on the particles surface, the gypsum combined with particles on the wood cross section and the gypsum combined with particles inside the wood cell cavity were selected and observed. Furthermore, the agglomeration and cementation mechanism between gypsum and particle were studied.

Current research on dosimeters based on radiation-induced attenuation (RIA) primarily focused on enhancing radiation sensitivity or reducing dependencies from interference factors. However, their intrinsic sensing performance has received limited attention. This work proposed application and analysis methods for RIA-based dosimeters, validated by a low-cost apparatus using commercial fibers. Initially, a generic protocol of high-dose detection after low-dose calibration was suggested to overcome the various dependencies of RIA, enabling repetitive monitoring of near-stable radiation by simple replacement of commercial fibers. Experiments comparing three dose-loss models demonstrated that the saturation-exponential model exhibited superior accuracy, achieving absolute errors below 4 Gy within a measurable range of up to ~300 Gy. Subsequently, the system’s RIA-based sensitivity was ~125.6 dB·Gy−1·km−1. The resolution and sensitivity expressed by optical power were newly defined, effectively quantifying the decline in precision and response ratio during detection. Moreover, an additional structure was introduced to extend the measurable range. Simulations and experiments under 1-MeV electron irradiation verified that adjustable ranges could be achieved through configuration of attenuation layers. In summary, these advancements provided critical guidance for component selection and operational evaluation, facilitating the commercialization and practical deployment of RIA-based dosimeters.

Introduction White blood cell count, a cost-effective blood test marker, is used extensively for the diagnosis and prognosis of diseases. Nevertheless, its association with the progression and prognosis of acute kidney injury remains unclear. Methods A retrospective analysis was conducted using data from a multicenter randomized trial on an acute kidney injury early warning system. Univariate analysis, multivariate logistic regression, and smooth curve fitting were used to evaluate the association between the white blood cell count and the progression and prognosis of acute kidney injury. Results A total of 5471 patients were included in the study. White blood cell counts were significantly associated with 14-day acute kidney injury progression (adjusted odds ratio: 1.04, 95% confidence interval: 1.02–1.06, P < 0.01) and 14-day mortality (adjusted odds ratio: 1.06, 95% confidence interval: 1.04–1.09, P < 0.01). However, white blood cell counts were not associated with 14-day dialysis (adjusted odds ratio: 1.01, 95% confidence interval: 0.97–1.05, P = 0.77). Further curve fitting analysis found a linear correlation between white blood cell counts and 14-day acute kidney injury progression and 14-day mortality. Conclusion White blood cell counts had a significant linear correlation with 14-day acute kidney injury progression and 14-day mortality, but not with 14-day dialysis.