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At least 235 records · Page 13
All sourcesNASA NTRSDOE OSTI
DOE OSTI2026

Helium co-implantation effects on dislocation loop evolution during in situ ion irradiations of a novel additive-manufactured Fe-9Cr steel alloy

This study examines the impact of helium injection rate on dislocation loop evolution during ion irradiation of a novel, additively manufactured (AM) 9Cr reduced-activation ferritic/martensitic (RAFM) steel. Through in situ transmission electron microscopy ion irradiations and post-irradiation characterization, the effects of simultaneous 1 MeV Kr²⁺ and 12 keV He⁺ ion irradiation at 400°C to 5 dpa with varying helium levels were examined. The findings reveal that helium co-injection significantly increases dislocation loop density, primarily through the formation of small defect features exhibiting contrast and projected morphologies consistent with a⟨100⟩ loops (∼1 nm), while suppressing larger a/2⟨111⟩ loops. The findings underscore the complex interplay among continuously increasing helium content, temperature, and alloy composition in the evolution of dislocation loops under irradiation in RAFM steels. The study highlights the need for further investigation into helium-mediated mechanisms, such as proposed interactions between self-interstitial atoms and helium atoms, to enhance the performance of RAFM steels in advanced nuclear reactors.

ANA2↗
DOE OSTI2018

Helium-implantation-induced lattice strains and defects in tungsten probed by X-ray micro-diffraction

Tungsten is the main candidate material for plasma-facing armour components in future fusion reactors. Bombardment with energetic fusion neutrons causes collision cascade damage and defect formation. Interaction of defects with helium, produced by transmutation and injected from the plasma, modifies defect retention and behaviour. Here we investigate the residual lattice strains caused by different doses of helium-ion-implantation into tungsten and tungsten-rhenium alloys. Energy and depth-resolved synchrotron X-ray micro-diffraction uniquely permits the measurement of lattice strain with sub-micron 3D spatial resolution and ~10 -4 strain sensitivity. Increase of helium dose from 300 appm to 3000 appm increases volumetric strain by only ~2.4 times, indicating that defect retention per injected helium is ~3 times higher at low helium doses. This suggests defect retention is not a simple function of implanted helium dose, but strongly depends on material composition and presence of impurities. Conversely, analysis of W-1 wt% Re alloy samples and of different crystal orientations shows that both the presence of rhenium, and crystal orientation, have a comparatively small effect on defect retention. These insights are key for the design of armour components in future reactors where it will be essential to account for irradiation-induced dimensional change when predicting component lifetime and performance.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Helium Incorporation into Scandium Fluoride, a Model Negative Thermal Expansion Material

Scandium trifluoride is a model negative thermal expansion (NTE) material. Its simple structure can be described as an A-site vacant perovskite, and it shows isotropic NTE over a very wide temperature range (up to ~1100 K), due to transverse vibrational motion of the fluoride. Like many framework NTE materials, it undergoes a phase transition at low pressures, adopting a rhombohedral (R3̅c) structure at >0.7 GPa and 300 K in commonly used nonpenetrating pressure media, such as silicone oil. High pressure X-ray diffraction data and gas uptake/release measurements indicate that, on compression in helium above ~200 K, helium is inserted into ScF 3 to form the defect perovskite He x ScF 3 . The incorporation of helium stiffens the structure and changes its phase behavior. At room temperature, complete filling of the structure with helium does not occur until >1.5 GPa. On compression, a cubic perovskite structure is maintained until ~5 GPa. As the pressure was increased to ~9.5 GPa, a further transition occurred at ~7 GPa. The first transition at ~5 GPa is likely to a tetragonal (P4/mbm) perovskite, but the detailed structure of the perovskite phase formed on compression above ~7 GPa is unclear. Cooling down from 300 to 100 K in helium at ~0.4 GPa leads to an approximate composition of He 0.1 ScF 3 . High pressure neutron diffraction measurements, in the temperature range 15–150 K show that the incorporation of helium increases the pressure at which the cubic (Pm3̅m) to rhombohedral (R3̅c) putative quantum structural phase transition occurs from close to 0 GPa to ~0.2 GPa at 0 K.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Simulations and Experiments Reveal Effect of Nanopores on Helium Diffusion in Quartz

The diffusion properties of noble gases in minerals are widely used to reconstruct the thermal histories of rocks. In this work, we combine density functional theory (DFT) calculations with laboratory experiments to investigate controls on helium diffusion in quartz. DFT calculations for perfect α-quartz predict substantially lower activation energies and frequency factors for helium diffusion than observed in laboratory experiments, especially in the [001] direction. These results imply that no helium could be retained in quartz at Earth surface temperatures, which conflicts with observations of partial cosmogenic 3 He retention over geologic time scales. Here, we implement a model of helium diffusion in α-quartz modulated by nanopore defects that disrupt energetically favorable diffusion pathways. In this model, we find that laboratory-determined diffusivities can be most closely reproduced when a helium atom encounters ~70 nanopore sites per million interstitial sites. The results of our model indicate that diffusion of helium in natural quartz, like other noble gases in other minerals, can be significantly modulated by extended defects.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2013

Effects of sequential tungsten and helium ion implantation on nano-indentation hardness of tungsten

To simulate neutron and helium damage in a fusion reactor first wall sequential self-ion implantation up to 13 dpa followed by helium-ion implantation up to 3000 appm was performed to produce damaged layers of {approx}2 {mu}m depth in pure tungsten. The hardness of these layers was measured using nanoindentation and was studied using transmission electron microscopy. Substantial hardness increases were seen in helium implanted regions, with smaller hardness increases in regions which had already been self-ion implanted, thus, containing pre-existing dislocation loops. This suggests that, for the same helium content, helium trapped in distributed vacancies gives stronger hardening than helium trapped in vacancies condensed into dislocation loops.

36 MATERIALS SCIENCE↗
DOE OSTI2014

Superfluid helium cryogenic systems for superconducting RF cavities at KEK

Recent accelerator projects at KEK, such as the Superconducting RF Test Facility (STF) for R and D of the International Linear Collider (ILC) project and the compact Energy Recovery Linac (cERL), employ superconducting RF cavities made of pure niobium, which can generate high gradient acceleration field. Since the operation temperature of these cavities is selected to be 2 K, we have developed two 2 K superfluid helium cryogenic systems for stable operation of superconducting RF cavities for each of STF and cERL. These two 2 K superfluid helium cryogenic systems are identical in principle. Since the operation mode of the cavities is different for STF and cERL, i.e. the pulse mode for STF and the continuous wave mode for cERL, the heat loads from the cavities are quite different. The 2 K superfluid helium cryogenic systems mainly consists of ordinary helium liquefiers/refrigerators, 2 K refrigerator cold boxes, helium gas pumping systems and high-performance transfer lines. The 2 K refrigerators and the high-performance transfer lines are designed by KEK. Some superconducting RF cavity cryomodules have been already connected to the 2 K superfluid helium cryogenic systems for STF and cERL respectively, and cooled down to 2 K successfully.

43 PARTICLE ACCELERATORS↗
DOE OSTI2014

Modeling the pressure increase in liquid helium cryostats after failure of the insulating vacuum

The pressure relief system of liquid helium cryostats requires a careful design, due to helium's low enthalpy of vaporization and due to the low operating temperature. Hazard analyses often involve the failure of the insulating vacuum in the worst-case scenario. The venting of the insulating vacuum and the implications for the pressure increase in the helium vessel, however, have not yet been fully analyzed. Therefore, the dimensioning of safety devices often requires experience and reference to very few experimental data. In order to provide a better foundation for the design of cryogenic pressure relief systems, this paper presents an analytic approach for the strongly dynamic process induced by the loss of insulating vacuum. The model is based on theoretical considerations and on differential equation modeling. It contains only few simplifying assumptions, which will be further investigated in future experiments. The numerical solutions of example calculations are presented with regard to the heat flux into the helium vessel, the helium pressure increase and the helium flow rate through the pressure relief device. Implications concerning two-phase flow and the influence of kinetic energy are discussed.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2014

Cavity morphology in a Ni based superalloy under heavy ion irradiation with cold pre-injected helium. I

In order to understand radiation damage in the nickel based superalloy Inconel X-750 in thermal reactors, where (n, α) transmutation reaction also occurred in addition to fast neutron induced atomic displacement, heavy ion (1 MeV Kr{sup 2+}) irradiation with pre-injected helium was performed under in-situ observations of an intermediate voltage electron microscope at Argonne National Laboratory. By comparing to our previous studies using 1 MeV Kr{sup 2+} irradiation solely, the pre-injected helium was found to be essential in cavity nucleation. Cavities started to be visible after Kr{sup 2+} irradiation to 2.7 dpa at ≥200 °C in samples containing 200 appm, 1000 appm, and 5000 appm helium, respectively, but not at lower temperatures. The cavity growth was observed during the continuous irradiation. Cavity formation appeared along with a reduced number density of stacking fault tetrahedra, vacancy type defects. With higher pre-injected helium amount, a higher density of smaller cavities was observed. This is considered to be the result of local trapping effect of helium which disperses vacancies. The average cavity size increases with increasing irradiation temperatures; the density reduced; and the distribution of cavities became heterogeneous at elevated temperatures. In contrast to previous characterization of in-reactor neutron irradiated Inconel X-750, no obvious cavity sink to grain boundaries and phase boundaries was found even at high doses and elevated temperatures. MC-type carbides were observed as strong sources for agglomeration of cavities due to their enhanced trapping strength of helium and vacancies.

36 MATERIALS SCIENCE↗
DOE OSTI2014

Laser induced fluorescence spectroscopy of the Ca dimer deposited on helium and mixed helium/xenon clusters

We study how the laser induced fluorescence spectroscopy of the calcium dimer deposited on pure helium clusters is modified by the addition of xenon atoms. In the wavelength range between 365 and 385 nm, the Ca dimer is excited from its ground state up to two excited electronic states leading to its photodissociation in Ca({sup 1}P)+Ca({sup 1}S): this process is monitored by recording the Ca({sup 1}P) fluorescence at 422.7nm. One of these electronic states of Ca{sub 2} is a diexcited one correlating to the Ca(4s4p{sup 3}P(+Ca(4s3d{sup 3}D), the other one is a repulsive state correlating to the Ca(4s4p1P)+Ca(4s21S) asymptote, accounting for the dissociation of Ca{sub 2} and the observation of the subsequent Ca({sup 1}P) emission. On pure helium clusters, the fluorescence exhibits the calcium atomic resonance line Ca({sup 1}S←{sup 1}P) at 422.7 nm (23652 cm{sup −1}) assigned to ejected calcium, and a narrow red sided band corresponding to calcium that remains solvated on the helium cluster. When adding xenon atoms to the helium clusters, the intensity of these two features decreases and a new spectral band appears on the red side of calcium resonance line; the intensity and the red shift of this component increase along with the xenon quantity deposited on the helium cluster: it is assigned to the emission of Ca({sup 1}P) associated with the small xenon aggregate embedded inside the helium cluster.

74 ATOMIC AND MOLECULAR PHYSICS↗
DOE OSTI2015

Molecular-dynamics analysis of mobile helium cluster reactions near surfaces of plasma-exposed tungsten

We report the results of a systematic atomic-scale analysis of the reactions of small mobile helium clusters (He{sub n}, 4 ≤ n ≤ 7) near low-Miller-index tungsten (W) surfaces, aiming at a fundamental understanding of the near-surface dynamics of helium-carrying species in plasma-exposed tungsten. These small mobile helium clusters are attracted to the surface and migrate to the surface by Fickian diffusion and drift due to the thermodynamic driving force for surface segregation. As the clusters migrate toward the surface, trap mutation (TM) and cluster dissociation reactions are activated at rates higher than in the bulk. TM produces W adatoms and immobile complexes of helium clusters surrounding W vacancies located within the lattice planes at a short distance from the surface. These reactions are identified and characterized in detail based on the analysis of a large number of molecular-dynamics trajectories for each such mobile cluster near W(100), W(110), and W(111) surfaces. TM is found to be the dominant cluster reaction for all cluster and surface combinations, except for the He{sub 4} and He{sub 5} clusters near W(100) where cluster partial dissociation following TM dominates. We find that there exists a critical cluster size, n = 4 near W(100) and W(111) and n = 5 near W(110), beyond which the formation of multiple W adatoms and vacancies in the TM reactions is observed. The identified cluster reactions are responsible for important structural, morphological, and compositional features in the plasma-exposed tungsten, including surface adatom populations, near-surface immobile helium-vacancy complexes, and retained helium content, which are expected to influence the amount of hydrogen re-cycling and tritium retention in fusion tokamaks.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2016

Mass separation of deuterium and helium with conventional quadrupole mass spectrometer by using varied ionization energy

Deuterium pressure in deuterium-helium mixture gas is successfully measured by a common quadrupole mass spectrometer (model: RGA200) with a resolution of ∼0.5 atomic mass unit (AMU), by using varied ionization energy together with new developed software and dedicated calibration for RGA200. The new software is developed by using MATLAB with the new functions: electron energy (EE) scanning, deuterium partial pressure measurement, and automatic data saving. RGA200 with new software is calibrated in pure deuterium and pure helium 1.0 × 10{sup −6}–5.0 × 10{sup −2} Pa, and the relation between pressure and ion current of AMU4 under EE = 25 eV and EE = 70 eV is obtained. From the calibration result and RGA200 scanning with varied ionization energy in deuterium and helium mixture gas, both deuterium partial pressures (P{sub D{sub 2}}) and helium partial pressure (P{sub He}) could be obtained. The result shows that deuterium partial pressure could be measured if P{sub D{sub 2}} > 10{sup −6} Pa (limited by ultimate pressure of calibration vessel), and helium pressure could be measured only if P{sub He}/P{sub D{sub 2}} > 0.45, and the measurement error is evaluated as 15%. This method is successfully employed in EAST 2015 summer campaign to monitor deuterium outgassing/desorption during helium discharge cleaning.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2014

Asteroseismic estimate of helium abundance of a solar analog binary system

16 Cyg A and B are among the brightest stars observed by Kepler. What makes these stars more interesting is that they are solar analogs. 16 Cyg A and B exhibit solar-like oscillations. In this work we use oscillation frequencies obtained using 2.5 yr of Kepler data to determine the current helium abundance of these stars. For this we use the fact that the helium ionization zone leaves a signature on the oscillation frequencies and that this signature can be calibrated to determine the helium abundance of that layer. By calibrating the signature of the helium ionization zone against models of known helium abundance, the helium abundance in the envelope of 16 Cyg A is found to lie in the range of 0.231 to 0.251 and that of 16 Cyg B lies in the range of 0.218 to 0.266.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2014

The initiation and propagation of helium detonations in white dwarf envelopes

Detonations in helium-rich envelopes surrounding white dwarfs have garnered attention as triggers of faint thermonuclear '.Ia' supernovae and double detonation Type Ia supernovae. However, recent studies have found that the minimum size of a hotspot that can lead to a helium detonation is comparable to, or even larger than, the white dwarf's pressure scale height, casting doubt on the successful ignition of helium detonations in these systems. In this paper, we examine the previously neglected effects of C/O pollution and a full nuclear reaction network, and we consider hotspots with spatially constant pressure in addition to constant density hotspots. We find that the inclusion of these effects significantly decreases the minimum hotspot size for helium-rich detonation ignition, making detonations far more plausible during turbulent shell convection or during double white dwarf mergers. The increase in burning rate also decreases the minimum shell mass in which a helium detonation can successfully propagate and alters the composition of the shell's burning products. The ashes of these low-mass shells consist primarily of silicon, calcium, and unburned helium and metals and may explain the high-velocity spectral features observed in most Type Ia supernovae.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2015

The effects of He I λ10830 on helium abundance determinations

Observations of helium and hydrogen emission lines from metal-poor extragalactic H II regions, combined with estimates of metallicity, provide an independent method for determining the primordial helium abundance, Y{sub p}. Traditionally, the emission lines employed are in the visible wavelength range, and the number of suitable lines is limited. Furthermore, when using these lines, large systematic uncertainties in helium abundance determinations arise due to the degeneracy of physical parameters, such as temperature and density. Recently, Izotov, Thuan, and Guseva (2014) have pioneered adding the He I λ10830 infrared emission line in helium abundance determinations. The strong electron density dependence of He I λ10830 makes it ideal for better constraining density, potentially breaking the degeneracy with temperature. We revisit our analysis of the dataset published by Izotov, Thuan, and Stasi and apos;nska (2007) and incorporate the newly available observations of He I λ10830 by scaling them using the observed-to-theoretical Paschen-gamma ratio. The solutions are better constrained, in particular for electron density, temperature, and the neutral hydrogen fraction, improving the model fit to data, with the result that more spectra now pass screening for quality and reliability, in addition to a standard 95% confidence level cut. Furthermore, the addition of He I λ10830 decreases the uncertainty on the helium abundance for all galaxies, with reductions in the uncertainty ranging from 10–80%. Overall, we find a reduction in the uncertainty on Y{sub p} by over 50%. From a regression to zero metallicity, we determine Y{sub p} = 0.2449 ± 0.0040, consistent with the BBN result, Y{sub p} = 0.2470 ± 0.0002, based on the Planck determination of the baryon density. The dramatic improvement in the uncertainty from incorporating He I λ10830 strongly supports the case for simultaneous (thus not requiring scaling) observations of visible and infrared helium emission line spectra.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2024

The impact of helium on plasma-driven hydrogen permeation and implications for direct internal recycling in the fusion fuel cycle

Abstract Metal foil pumps (MFPs) are the leading technology for direct internal recycling (DIR) of hydrogen isotopes from the plasma exhaust in future fusion plants. MFPs rely on the concept of superpermeation, where superthermal H atoms directly absorb into the metal foil, rapidly diffuse, and desorb downstream. To date, studies of superpermeation have predominantly employed either pure hydrogen or in some cases trace levels of impurities. The plasma exhaust is expected to contain just ∼1% helium, but in DIR the source gas would be enriched in helium as hydrogen isotopes are extracted. In this work, we explore the impact of helium on hydrogen superpermeation at low temperature (75 °C–200 °C) using Pd-based foils. To first order, the flux scaled linearly with the hydrogen mole fraction. Stable permeation was observed until the helium fraction reached ∼80%, where the flux began to decline slowly with time. In addition, short term (1–5 min) exposure to pure helium plasma significantly attenuated subsequent hydrogen plasma permeation, and the degree was more dramatic at elevated temperature. This attenuation was correlated with He retention in the foils, which was detected by time-of-flight secondary ion mass spectrometry at low levels (<0.1 at. %) and limited to the near surface (<10 nm). Similar trends were observed among all alloys (Pd, PdAg, PdCu), and the foils were restored to full performance with an Ar + sputter clean. The potential for helium plasma exposure to impact MFP performance under these conditions has not been previously reported, and these findings have significant implications to the design and implementation of practical DIR systems.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2026

Background-Oriented Schlieren Velocimetry of Helium Coolant Flow in Additively Manufactured Channels

High-pressure helium gas cooling is an attractive solution for thermal management of the fusion blanket first wall, as this coolant is chemically and neutronically inert and separable from hydrogenic species. However, due to the low thermal mass of helium, geometric optimization of these channels is required to provide sufficient cooling at manageable flow rates and pumping burdens. Increasingly, analysis and optimization of these coolant channels rely on computational fluid dynamics (CFD) simulations, and these require relevant experimental data for turbulence model validation. Toward this end, a high-pressure helium gas flow visualization system has been employed to image the flow of helium in flow channels with one-sided heating, mimicking the blanket first wall environment. Flow of helium at 4 MPa pressure and flow rates up to 68 g/s (Reynolds number 57 000) is supplied to rectangular channel test sections, with uniform heating applied to the bottom wall of the channel at heat fluxes varied between roughly 50 and 130 kW/m2. A high-speed camera is used to image index of refraction (IOR) gradients in the fluid via background-oriented schlieren (BOS), and temperature and pressure instrumentation are used to characterize thermal-hydraulic performance of each channel. Cross correlation of time-resolved BOS images is then used to calculate time-averaged 2-D helium velocity fields. Flow in additively manufactured (AM) channels is examined in this manner, including both featureless channels and those containing baffling as a heat transfer enhancement. The flow distribution seen in the featureless case differs significantly from that seen in prior simulations, whereas the flow in the baffled case shows the predicted behavior of flow forced along the heated wall. This augmented flow distribution is seen to increase the heat transfer coefficient in the baffled test section. Here, strategies are discussed for ongoing and future validation of these simulations, with the aim of model deployment for blanket cooling design and optimization.

Additive manufacturing↗
DOE OSTI2016

WE-AB-202-07: Ventilation CT: Voxel-Level Comparison with Hyperpolarized Helium-3 & Xenon-129 MRI

Purpose: To compare the spatial correlation of ventilation surrogates computed from inspiratory and expiratory breath-hold CT with hyperpolarized Helium-3 & Xenon-129 MRI in a cohort of lung cancer patients. Methods: 5 patients underwent expiration & inspiration breath-hold CT. Xenon-129 & {sup 1}H MRI were also acquired at the same inflation state as inspiratory CT. This was followed immediately by acquisition of Helium-3 & {sup 1}H MRI in the same breath and at the same inflation state as inspiratory CT. Expiration CT was deformably registered to inspiration CT for calculation of ventilation CT from voxel-wise differences in Hounsfield units. Inspiration CT and the Xenon-129’s corresponding anatomical {sup 1}H MRI were registered to Helium-3 MRI via the same-breath anatomical {sup 1}H MRI. This enabled direct comparison of CT ventilation with Helium-3 MRI & Xenon-129 MRI for the median values in corresponding regions of interest, ranging from finer to coarser in-plane dimensions of 10 by 10, 20 by 20, 30 by 30 and 40 by 40, located within the lungs as defined by the same-breath {sup 1}H MRI lung mask. Spearman coefficients were used to assess voxel-level correlation. Results: The median Spearman’s coefficients of ventilation CT with Helium-3 & Xenon-129 MRI for ROIs of 10 by 10, 20 by 20, 30 by 30 and 40 by 40 were 0.52, 0.56, 0.60 and 0.68 and 0.40, 0.42, 0.52 and 0.70, respectively. Conclusion: This work demonstrates a method of acquiring CT & hyperpolarized gas MRI (Helium-3 & Xenon-129 MRI) in similar breath-holds to enable direct spatial comparison of ventilation maps. Initial results show moderate correlation between ventilation CT & hyperpolarized gas MRI, improving for coarser regions which could be attributable to the inherent noise in CT intensity, non-ventilatory effects and registration errors at the voxel-level. Thus, it may be more beneficial to quantify ventilation at a more regional level.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2017

Thermodynamic parameters of helium under shock-wave and quasi-isentropic compressions at pressures up to 4800 GPa and compression ratios up to 900

The thermodynamic parameters of a strongly nonideal helium plasma obtained in experimental devices of hemispherical and spherical geometries are presented. Under shock-wave loading in the hemispherical device, the helium plasma was compressed to a density ρ ≈ 0.76 g cm{sup –3} by a pressure P ≈ 83 GPa at a temperature T ≈ 51000 K. Two-cascade spherical experimental devices of two types were used under quasi-isentropic helium plasma compression. In the devices of the first type at the same initial gas pressure in both cavities of the shells, the helium plasma was compressed approximately by a factor of 200 to a density ρ ≈ 8 g cm{sup –3} by a pressure P ≈ 4800 GPa. In the devices of the second type at a ratio of the initial gas pressures in the cavities of about 9: 1, the thermodynamic parameters of a nonideal helium plasma compressed by a factor of 900 to a density ρ ≈ 5 g cm{sup –3} by a pressure P ≈ 3700 GPa were determined. The compressed-plasma pressure was determined from the results of gasdynamic computations. An X-ray radiograph consisting of three betatrons and a multichannel optoelectronic X-ray imaging system was used to determine the positions of the boundaries of the gaseous-helium-compressing steel shell.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗