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Recent experiments have confirmed the compatibility of extended boron particulate injections with high performance plasma discharges in the full tungsten (W) environment of WEST. Utilizing an impurity powder dropper (IPD) equipped with boron (B) powders a series of extended experimental programs providing controlled injections have quantified plasma response to varying levels of injection rate and total injection quantity. Calibration of injection quantities confirmed through post-situ testing of the IPD and cross-correlated with both high-speed camera illumination and spectroscopic measurement have allowed for the first time a fine scale determination of the effects of powder introduction on plasma performance. Plasma enhancement, consistent with turbulence reduction through profile modification, has been observed with sustained increases in the stored energy (WMHD), by 18%, electron temperature (Te) by 35%, and neutron rate (Nn) by up to 200%, all of which scale positively with increasing powder injection rates. These injections have also resulted in both prompt and extended reductions in native impurity content, decreases in post injection radiated power, and strong decreases in divertor deuterium signatures signifying a reduction in recycling suggesting enhanced boron layer formation which provides a reduction of source terms and leads to enhanced gettering of main ion and impurity sources.

The effects of germanium (Ge)-doping with concentrations in the range of 10 18 –10 20  cm −3 on oxygen precipitation (OP) in Czochralski (CZ) silicon wafers subjected to the low (800 °C)–high (1000 °C) two-step anneal following the rapid thermal anneal (RTA) at 1250 °C, which is actually the RTA-based internal gettering (IG) process, have been comprehensively investigated. It is found that whether the Ge-doping enhances or suppresses OP in the CZ silicon wafers with the aforementioned three-step anneal is quite dependent on the Ge-doping concentration and on the nucleation time at 800 °C. On the one hand, the Ge-doping is experimentally and theoretically revealed to facilitate the formation of vacancy-oxygen (VO m , m ≥ 1) complexes in the CZ silicon wafer during the prior RTA at 1250 °C. In this sense, the Ge-doping enhances the nucleation of oxide precipitates thus being beneficial for OP. On the other hand, the considerably high concentration of Ge-doping introduces compressive stress into silicon lattice in a manner due to the slightly larger covalent radius of Ge atom. Such introduced compressive stress not only increases the critical size required for the onset growth of oxide precipitate nuclei at 1000 °C but also suppresses the growth of oxide precipitates in the course of 1000 °C anneal. Thus, the Ge-doping is unfavorable for the growth of oxide precipitates. Based on the advantageous and disadvantageous effects of Ge-doping on the nucleation and growth of oxide precipitates, respectively, which have been definitely revealed in this work, the above finding has been essentially understood. Of practical significance, this work offers technological guideline to improve the IG capability of CZ silicon wafer through adopting appropriate Ge-doping and RTA-based annealing scheme.

Enhanced deuterium retention in tantalum (Ta) cold spray coatings, compared to reference polycrystalline tantalum and tungsten materials, has been evaluated using the thermal desorption spectrometry technique. Tantalum coatings, deposited via cold spray technology on 316L stainless steel substrates, are proposed as plasma-facing material surfaces with hydrogen gettering functionality for advanced fusion concepts. The materials were exposed to 95 eV D ions at a flux of 1.6– 3.5×1021 D m−2 s−1. Retention was measured as a function of incident ion fluence and surface temperature. The results highlight an increased deuterium inventory in Ta cold spray coatings by a factor of 3.5 compared to polycrystalline tantalum and by two orders of magnitude compared to polycrystalline tungsten. A tendency for retention saturation in tantalum is observed at a fluence above 1×1024 D m−2. While deuterium retention gradually decreases with increasing surface temperature from 400 K to 925 K for polycrystalline tungsten, it remains constant for polycrystalline tantalum. In contrast, retention in Ta coatings significantly decreases when the surface temperature exceeds 750 K. The microstructure of the cold spray Ta coatings plays a crucial role in the dynamics of deuterium trapping and release. Tantalum also exhibits a superior resistance to blister formation compared to tungsten when subjected to a high dose of deuterium.

Boronization is a widely employed technique for oxygen gettering and impurity suppression. It is expected to be an initial routine wall conditioning method for tungsten (W) plasma-facing components (PFCs) in ITER. To assess boron (B) performance under metal wall conditions, experimental campaigns with boronization were conducted in the Experimental Advanced Superconducting Tokamak. A quartz crystal microbalance installed at the mid-plane of port C (C-QMB), positioned 0.5 m behind the limiter, enabled in-situ monitoring of material erosion and deposition in magnetic shadowed areas during the wall conditioning processes and subsequent plasma discharges. Material erosion was detected in the majority (>50%) of discharges, regardless of whether they were normal plasma operations or terminated by disruptions. Transitions from erosion to deposition during normal discharges at the C-QMB have been shown to provide critical insights for estimating the lifetime of B-based coatings on nearby PFCs. Erosion rates were also found to be significantly influenced by the heating configuration. Electron cyclotron resonance heating (ECRH) discharges induced erosion rates 1.95 times higher than those in combined lower hybrid wave and ECRH discharges. Following a single boronization using 10 g of carborane, the B-based coating on C-QMB exhibited a lifetime of ∼104 s under plasma exposure. Post-mortem analyses revealed that about 30 nm of a boron-carbon film remained on the C-QMB, demonstrating strong oxygen gettering capability and minor iron and copper contamination. This residual film exhibited a deuterium retention at a level of 2.12 × 1020 m−2, more than eight times higher than that of pure W, highlighting the pronounced trapping capacity of B-containing films in low-flux regions. These results provide valuable insights into the application of boron in next-step devices such as ITER.

We began our careers in public health practice around the time of the release of the landmark 1988 report, The Future of Public Health (FOPH).1 Perhaps the most widely publicized quote in the report was \"this nation has lost sight of its public health goals and has allowed the system of public health to fall into disarray.\"1(p1) The FOPH highlighted the fragmented and non-interconnected public health system, along with public complacency. While the theme of disarray was the attention getter, many other topics have resonated in the intervening 35years, showing the prescience of the FOPH, including the introduction of core functions of public health, the central role of science, and ongoing gaps in workforce development.Many others have expanded upon and critiqued the FOPH report. Critiques included a lack of a national vision and too much emphasis on site visits to six states.2 Largely missing was a central focus on health equity, particularly a focus on historical structural drivers of inequities.Multiple other reports from the Institute of Medicine covered related themes, including a 2003 report that focused on a policy approach to population health, the need to emphasize broader determinants of health, the power of partnerships, and the need for systems to address accountability and communication.3 Three related committees reviewed population health strategies, metrics, and interventions4; how statutes and regulations can optimize health outcomes5; and recommendations for funding state and local health systems6We provide our current snapshot of public health in light of the 1988 FOPH report and those that followed-we assess where we are making significant progress (\"the good\"), where progress is lagging (\"the bad\"), and where there are strong warning signs and harms (\"the ugly\"). Because we allocate more space to what needs more attention, our inclusion of \"the good\" will be brief.

Compliance with imposed hydrogen concentration limits in the lithium loop of the DEMO-Oriented Neutron Source (DONES) requires the installation of an yttrium-based hydrogen trap. To determine an appropriate H-trap design, it is essential to have access to a numerical tool capable of simulating hydrogen transport in the DONES lithium loop connected to an yttrium pebble-bed. In the past, a simplified model was created that allows such calculations when hydrogen concentrations in the lithium are low. However, in certain DONES operating phases, the concentration in the lithium is high and in a range where yttrium dihydride (YH 2 ) formation is likely. Due to the anticipated great impact of YH 2 formation on the H-trap performance a new model is developed that includes the mechanism of hydride formation. It is based on a mathematical reproduction of complete pressure-composition isotherms of the Li–H and Y–H systems. Thus, the conditions that trigger YH 2 formation are determined and the variation of hydrogen solubility in different yttrium hydride phases is deduced. An approximate concentration-dependent relationship of hydrogen diffusivity in yttrium is derived and incorporated into the model. Simulations are performed to analyze the dynamics of the concentration decrease during purification of the lithium circuit prior to the experimental DONES phase by varying design parameters of the trap. It is found that hydride formation greatly increases the hydrogen gettering capacity of the H-trap and limits the maximum concentration in the lithium. Indeed, YH 2 formation may be purposefully triggered to exploit its beneficial properties for DONES. Simulations of the hydrogen purification process during the experimental phase of DONES show that the H-trap must be replaced at least every 28 days to meet tritium limits. This work sets the conditions for the required pebble-bed mass of the H-trap at a given temperature to comply with the DONES safety requirements. Finally, the model is validated by numerical reproduction of experimental results.

The paper considers a mathematical model of the technical process of external gettering of silicon rods. The purpose of this process is to remove unwanted impurities from silicon. The model of this process is an initial-boundary value problem for a linear partial differential equation of parabolic type. A feature of this problem is the presence of a nonlocal in time boundary condition, which reflects the law of conservation of mass (matter). For numerical modeling, an algorithm based on difference approximations of differential operators of the 1st and 2nd order is proposed. The classical sweep method is used to find a solution to a discrete problem.

The impact of hydrocarbon-molecular (C3H6)-ion implantation in an epitaxial layer, which has low oxygen concentration, on the dark characteristics of complementary metal-oxide-semiconductor (CMOS) image sensor pixels was investigated by dark current spectroscopy. It was demonstrated that white spot defects of CMOS image sensor pixels when using a double epitaxial silicon wafer with C3H6-ion implanted in the first epitaxial layer were 40% lower than that when using an epitaxial silicon wafer with C3H6-ion implanted in the Czochralski-grown silicon substrate. This considerable reduction in white spot defects on the C3H6-ion-implanted double epitaxial silicon wafer may be due to the high gettering capability for metallic contamination during the device fabrication process and the suppression effects of oxygen diffusion into the device active layer. In addition, the defects with low internal oxygen concentration were observed in the C3H6-ion-implanted region of the double epitaxial silicon wafer after the device fabrication process. We found that the formation of defects with low internal oxygen concentration is a phenomenon specific to the C3H6-ion-implanted double epitaxial wafer. This finding suggests that the oxygen concentration in the defects being low is a factor in the high gettering capability for metallic impurities, and those defects are considered to directly contribute to the reduction in white spot defects in CMOS image sensor pixels.

Titanium zirconium vanadium (TiZrV) is a widely used non-evaporable getter (NEG) material with the characteristics of a low activation temperature and a large gas absorption capacity. At present, the research on TiZrV getters mainly focuses on the thin-film state, with little research on the bulk state. In this paper, a TiZrV getter was optimized by adding Al, and the phase structure, activation properties, and gettering performance were studied. With the addition of Al, the α-Zr phase and Ti2Zr phase changed into the Ti-Zr phase and Al-Zr, Al-Ti phase. The newly generated phase promoted the diffusion of hydrogen and oxygen atoms. The activation temperature decreased significantly, as shown in the in situ XPS results. The H2 and CO gettering performance of TiZrVAl samples was promoted to 2073 cm3·s−1 and 1912.8 cm3·s−1, increased by 40.7% and 40.3%. This paper provides valuable ideas for optimizing the properties of bulk TiZrV getters.

We developed silicon epitaxial wafers with high gettering capability by using hydrocarbon–molecular–ion implantation. These wafers also have the effect of hydrogen passivation on process-induced defects and a barrier to out-diffusion of oxygen of the Czochralski silicon (CZ) substrate bulk during Complementary metal-oxide-semiconductor (CMOS) device fabrication processes. We evaluated the electrical device performance of CMOS image sensor fabricated on this type of wafer by using dark current spectroscopy. We found fewer white spot defects compared with those of intrinsic gettering (IG) silicon wafers. We believe that these hydrocarbon–molecular–ion–implanted silicon epitaxial wafers will improve the device performance of CMOS image sensors.