Successive Irradiation Research Articles

Syringeable Self-Organizing Gels that Trigger Gold Nanoparticle Formation for Localized Thermal Ablation.

Block copolymer dispersions that form gels at body temperature and that additionally are able to reduce a gold salt to nanoparticles (AuNPs) directly in the final formulation under mild conditions were designed as hybrid depots for photothermal therapy. The in situ gelling systems may retain AuNPs in the application zone for a long time so that localized elevations of temperature can be achieved each time the zone is irradiated. To carry out the work, dispersions were prepared covering a wide range of poloxamine Tetronic 1307:gold salt molar ratios in NaCl media (also varying from pure water to hypertonic solution). Even at copolymer concentrations well above the critical micelle concentration, the reducing power of the copolymer was maintained, and AuNPs were formed in few hours without extra additives. Varying the copolymer and NaCl concentrations allowed a fine tuning of nanoparticles’ shape from spherical to triangular nanoplates, which determined that the surface plasmon resonance showed a maximum intensity at 540 nm or at 1000 nm, respectively. The information gathered on the effects of (i) the poloxamine concentration on AuNPs’ size and shape under isotonic conditions, (ii) the AuNPs on the temperature-induced gelling transition, and (iii) the gel properties on the photothermal responsiveness of the AuNPs during successive irradiation cycles may help the rational design of one-pot gels with built-in temperature and light responsiveness.

Photo-control of poly(N-[4-[(4-Nitrophenyl)azo]phenyl]acrylamide) brushes on graphene oxide coated silicon surface

Poly(N-[4-[(4-Nitrophenyl)azo]phenyl]acrylamide [poly(NPAPAA)] brushes were obtained via interface-mediated reversible addition–fragmentation chain transfer polymerization to design new photoresponsive surface on the graphene oxide coated silicon substrate. Switchable surface wettability was controlled successfully by these densely packed polymer brushes using light as the exterior stimulation. The relatively nonpolar trans azobenzene polymer brushes were converted to a polar cis form (with a larger dipole moment) utilizing light of the suitable wavelength. This conversion is reversible and can be switched back by employing visible light. Cis–trans photo-induced isomerization provided a reversible contact angle change (~ 9o) with UV and visible light for the poly(NPAPAA) brushes under successive irradiation cycles. This study may be promised to control cell culture surface without leaving any residual in terms of alternative medicine.

Effect of thermal annealing and irradiation damage on the superconducting critical temperature of nanocrystalline γ-Mo2N thin films

We report on the influence of the disorder and stoichiometry in the resulting superconducting critical temperature of γ-Mo2N thin films. Initially, three films (with Tc values of 7.6 K, 6.8 K and 6 K) were grown at room temperature by reactive sputtering, on Si (1 0 0) using different N2/(Ar+N2) mixtures. The influence of the thermal annealing up to 973 K and irradiation damage produced by 1 MeV Zr+(fluence up 2 × 1014 cm−2) is analyzed. The Tc of pristine films remains unchanged for increasing irradiation doses up 2 × 1014 cm−2. The Tc for annealed films decreases close to the value expected for bulk samples (≈5 K) for increasing the annealing temperature. Successive irradiations of the annealed films tend to increase their Tc up to its initial values (before annealing). The results indicate that the Tc in nanometric grain size γ-Mo2N thin films is affected by both nitrogen stoichiometry and disorder at the atomic scale.

Application of the Calculating Formula for the Mean Neutron Exposure in CEPM-s and CEPM-r/s Starstwo

Recent studies have shown that for the current s-process nucleosynthesis models of low-mass asymptotic giant branch (AGB) stars with a radiatively burning C13 pocket in the interpulse period, the neutron exposure distribution in the nucleosynthesis region can be regarded as an exponential function, and the relation between the mean neutron exposure τ0 and the model parameters is τ0=−Δτ/ln[q/(1−r+q)], in which Δτ is the exposure value of each neutron irradiation, r is the overlap factor, and q is the mass ratio of the C13 pocket to the He intershell. Using the published data resulted from fitting the observed abundances of neutron-capture elements in 20 CEMP (Carbon-Enhanced Metal-Poor)-s and CEMP-s/r stars with the parameterized s-process nucleosynthesis model of AGB stars, the reliability of the formula for calculating the mean neutron exposure is tested, and further more the application of the formula in the study of heavy-element s-process nucleosynthesis is explored preliminarily. Our results show that under the radiative s-process nucleosynthesis mechanism, the formula is suitable for the CEMP stars experienced multiple successive neutron irradiations. Combined with the parameterized AGB star nucleosynthesis model, the formula could be regarded as an effective tool to select the CEMP stars of single neutron exposure or special type. But considered the uncertainty of the C13 pocket, the role of this formula in understanding the physical conditions necessary for reproducing the observed abundances of neutron-capture elements in CEMP stars needs further studies.

Surface Structure Transformation in Double Forged Tungsten upon Single and Sequenced Irradiation Using Different Types of Radiation Facilities

Structural changes in the surface layer of target samples made of double forged tungsten were investigated after successive pulsed plasma irradiation thereof using different irradiation facilities such as plasma focus (PF), plasma gun (PG), and plasma accelerator (PA). The irradiation modes simulated hard conditions occurring under the action of thermonuclear plasma on the material in modern tokamaks in such extreme situations as plasma disruption, vertical displacement, and edge localized mode effects (ELMs). Hydrogen and deuterium were used as working gases. Double forged tungsten (DFW) samples were irradiated using PF facilities (PF-6 and PF-1000U) with a subsequent irradiation using PG or PA, as well as another sequence consisting in the initial irradiation using PA and a subsequent irradiation using PF-6 at the final stage. The DFW samples in the experiments were positioned normal to the incident energy flux. The following irradiation modes were used. The PF-1000U facility provides a power density of the deuterium plasma flux onto the target surface qpl = 109–1010 W/cm2, pulse duration τpl = 50–100 ns, power density of the of fast ion beam (with energy Ei > 100 keV) qfi = 1011–1012 W/cm2, pulse duration τfi = 10–50 ns. The PF-6 facility provides qpl = 109–1010 W/cm2, τpl = 50 ns, qfi = 1010–1011 W/cm2, τfi = 10–50 ns. The PG facility provides energy density Q = 0.8 MJ/m2, density of hydrogen plasma q ≈ 5 × 106 W/cm2, pulse duration τ = 15 μs. The PA facility provides Q = 0.75 MJ/m2, power density of deuterium plasma q = 3.6 × 105 W/cm2, τ = 0.25 ms. General features and peculiarities inherent in tungsten damage and changes in the structural state thereof under the action of energy flows in the hard mode of preliminary irradiation in PF facilities with subsequent radiation exposure in softer modes implemented in PG and PA facilities are considered. It is shown that, in the irradiation modes under investigation, the character of material degradation depends not only on the magnitude and duration of the single energy pulses generated by a testing facility but also on the number of energy pulses. The depth of the apparent damaged layer, wherein the crippling of the material occurs, is about 200 μm in almost all the studied irradiation modes, the damage being of thermal and shock-wave nature.

Damage effects of Au&He dual ion irradiated silicon carbide

Synergistic effects of Au and He dual ion beam irradiations were investigated by comparing the damage accumulated in single crystalline silicon carbide (SiC). By implanting Au ions at 600 K and He ions at room temperature into 6H-SiC, the resulting damage was characterized using several advanced techniques, including Raman spectroscopy, Rutherford backscattering spectrometry in channeling mode (RBS/C), nano-indentation and high-resolution x-ray diffraction (HRXRD). Here, we report the complex effects induced by dual ion beam irradiations and we also investigate the isothermal annealing effects on dual ion irradiation damage. Synergy effects of Au and He dual irradiations have been observed. Irradiation damage produced by Au&He ions is larger than single ion irradiation. The displacement damage induced by heavy recoil atoms and helium atoms interact with each other, causing more serious damage. Interestingly, Au + He successive irradiation induced a larger damage level than He + Au successive irradiation, probably due to thermal annealing effect during Au irradiation. Finally, the hardness and Young’s modulus of irradiated SiC were found to be highly related with single or dual ion irradiations, implantation sequences and the corresponding fluences.

Does Tetrahydrofuran (THF) Behave like a Solvent or a Reactant in the Photolysis of Thionyl Chloride (Cl2SO) in Cyclohexane? A Transient Infrared Difference Study.

The photolysis of thionyl chloride (Cl2SO) in pure cyclohexane (cHex) and in cHex with a small amount of tetrahydrofuran (THF) irradiated with 266 nm pulsed laser was investigated using time-resolved step-scan Fourier-transform spectroscopy. The density functional theory B3LYP, with the conductor-like polarizable continuum model to account for the effects of solvents, was employed to predict the molecular parameters of the relevant species. Monitoring the wavenumbers and infrared absorbances attributed to the [S,O] species and accounting for the stoichiometry revealed SO2 to be the major oxygen-containing end product for the thermal decomposition of Cl2SO. Upon successive irradiation with 266 nm pulsed laser, the major product, as detected by IR absorption, was S2O with minor SO3, which could be generated from the secondary reactions of the photolytic intermediate ClSO. The majority of the transient vibrational features upon 266 nm irradiation of the mixture of Cl2SO/cHex was attributed to ClSO, characterized at 1155 cm-1, coupled with a minor contribution of (ClSO)2 at 1212 and 1173 cm-1. For the mixture of Cl2SO/THF/cHex, the transient population of ClSO was retained, but the amount of (ClSO)2 was slightly reduced, coupled with a new upward feature at 1054 cm-1 that was plausibly attributed to the C-O-C asymmetric stretching mode of ClSO-THF complex. Upon the successive irradiation of the Cl2SO/THF/cHex mixture, the amount of S2O was also decreased. The observed complexes of THF with solutes suggested that THF should not be merely treated as a solvent but regarded as a coordination molecule in organic synthesis. The formation of the intermediate-THF complexes altered the reaction pathways, as well as the types and populations of the end products.

Thermoluminescence behavior of Sm3+ activated ZnB2O4 phosphors synthesized using low temperature chemical synthesis method

Abstract This study is mainly centered on thermoluminescence (TL) behavior under beta excitation at room temperature (RT) of Sm3+ activated ZnB2O4 phosphors synthesized by low temperature chemical synthesis method. The prepared phosphors were characterized by the X-ray powder diffraction (XRD) method. The effects of dopant concentration, beta radiation dose (0.115–69 Gy) and heating rate (0.5–10 °C/s) on TL intensity of Sm3+ doped ZnB2O4 phosphors and reproducibility are investigated using a lexsyg smart TL/OSL reader system. The activation energy values, E obtained from the analysis of the TL glow curve were calculated with initial rise (IR) method and peak shape (PS) method over the deconvoluted glow curves. The Ea–Tstop and CGCD methods indicated that the glow curve of this phosphor is the superposition of at least six components, which were called to as P1–P6, in the temperature range between RT and 400 °C. The results reveal that 2% Sm3+ doped ZnB2O4 gives optimum TL response, the relative intensity of the glow peak increases linearly with increase of beta dose and, the peaks of TL glow curves shift towards the higher temperature side with increase in heating rate as the total area under the glow peak remains the same. The maximum variation of reproducibility for ten successive irradiation cycles of 20.7 Gy is less than 3% from the average value and the sample doped 2% Sm3+ shows a good stability for the reusability. Additionally, the results obtained from IR and PS methods indicates that the complex glow curve is composed of six distinguishable peaks.

Feasibility of 153Sm production using MNSR research reactor through a multi-stage approach

The main objective of this study was to explore the feasibility of producing 153Sm radioisotope in miniature neutron source reactors (MNSRs) in Isfahan-Iran. As the first step of this study, the MNSR's geometry was created by using the MCNP6.2 simulation code and afterwards a validity check was performed by comparing the results with the experimental data. Then, by applying values obtained through simulation, the production process was followed up to 20 irradiation cycles using different irradiation and cooling periods (irradiation setups). The results showed that the proposed simulation technique has an acceptable agreement with the experiments (with a difference of nearly 6%). In spite of limitations, such as irradiation time and flux in such reactors, our results showed that by choosing the correct irradiation setup, it is possible to produces 153Sm up to 852.26 mCi g−1 in 20 successive irradiation cycles. However, after the 10th cycle, the production reached 90% of the maximum point. Nevertheless, the continuance of the irradiation process with a new target (by 10 plus 10 discrete irradiation) can double the total activity in comparison with 20 successive irradiation cycles, without any increase in the fuel consumption of the reactor. These findings increase the prospect of a large-scale production of the life-saving 153Sm radioisotope in MNSR reactors.

Microwave irradiation’s effect on promoting coalbed methane desorption and analysis of desorption kinetics

To enhance desorption of coalbed methane and increase extraction efficiency, a technique using microwave irradiation is proposed. Methane desorption experiments without and with microwave irradiation were carried out in the laboratory using an experimental system developed to study methane desorption. The experimental results show that microwave irradiation causes the total quantity of methane desorbed to increase from 1.91 to 3.92 times larger than the quantity desorbed without MI. Two hour trials were performed, applying microwaves for 4, 8 or 16 min, equivalent to output energies of 192, 384 and 768 kJ. These results show that 1 kJ of microwave energy can cause methane desorption to increase by 0.0088 ml per gram of coal. Under successive microwave irradiations of 40 s, the desorption rate increases by a factor of 10.2. Kinetic analysis also found that microwave irradiation enhances the methane diffusion coefficient and decreases the attenuation coefficient. Regardless of which diffusion model is used to determine the diffusion coefficient, the quantity of gas desorbed increases as the microwave irradiation time increases. The pore and surface features of coal samples exposed to microwaves were determined by using mercury intrusion porosimetry and nitrogen adsorption and specimens were examined by scanning electron microscopy. Methane desorption evidently results from both the microwave thermal effect and structural damage to the coal. The results reported herein reveal the mechanisms that promote methane desorption by microwave irradiation and suggest a new field technique for extracting coalbed methane.

A Novel Cyanine and Porphyrin Based Theranostic Nanoagent for Near-Infrared Fluorescence Imaging Guided Synergistic Phototherapy

Design and synthesis of multifunctional organic nanoparticles (NPs) for non-invasive diagnosis and phototherapy of cancer are widely acknowledged. However, limited drug loading of NPs are major limitations for attaining synergistic effect in most of the combination therapies. Herein, a novel cyanine-porphyrin combined NPs (PGL-DiR) was fabricated in a simple and inexpensive way for the treatment of prostate cancer. A most commonly used near-infrared fluorescent (NIRF) cyanine dye, DiR was chosen as a photothermal agent to encapsulate in a porphyrin grafted lipid (PGL) (PGL-DiR) NPs of average size 156.25±31.31 nm. Unlike conventional liposomes, the self-assembled PGL morphology revealed encapsulation efficiency of DiR higher than 98%. However, as observed in vitro, DiR loading contents could trigger obvious quenching of singlet oxygen (1O₂) by PGL thereby reducing the efficiency of PDT. Nevertheless, after successful photobleaching of DiR, as prepared PGL-DiR NP could facilitate enhanced synergistic photothermal and photodynamic (PTT-PDT) therapy both in vitro and in vivo. After intravenous administration of PGL-DiR NPs in a PC3 tumor xenograft mice, a high accumulation in tumor until 24 hrs was clearly evident via NIRF imaging. With the successive laser irradiation, these NPs effectively suppressed the tumor growth synergistically as PTT < PDT < PTT + PDT while compared to monotherapies such as PTT or PDT alone. These results demonstrated that as prepared PGL-NPs could serve as an excellent theranostic agent both in vitro and in vivo for combined therapy of prostate cancer.

Human pupillary light reflex during successive irradiation with 1-ms blue- and green-pulsed light

BackgroundIn the human retina, the contribution of intrinsically photosensitive retinal ganglion cells (ipRGCs) to the regulation of the pupillary response remains poorly understood. The objective of the current study was to determine the response dynamics of the pupillary light reflex to short, successive pulses of light. In order to better assess the roles of ipRGCs and cones, we used pulses of blue and green light.MethodsEach participant was exposed to 1-ms blue (466 nm) and/or green (527 nm) light pulses simultaneously or separately, with inter-stimulus intervals (ISIs) of 0, 250, 500, 750, or 1000 ms. Pupil diameter was measured using an infrared camera system.ResultsWe found that human pupillary light responses during simultaneous irradiation or successive irradiation with ISIs ≤ 250 ms were equivalent, though successive irradiation of blue- and green-pulsed light with ISIs ≥ 500 ms induced markedly increased pupillary constriction.ConclusionsWe propose that this result may be related to cell hyperpolarization that occurs in the retina just after the first light stimulus is turned off, with the threshold for this effect being between 250 and 500 ms in the human retina.

Evolution of microstructure and mechanical properties of SUS430/C11000/SUS430 composites during the laser-forming process

Multilayered sheet metals have been widely used to achieve a wide range of favorable mechanical, physical, thermal and electrical properties. Laser beam irradiation over these materials creates extreme temperature changes that can lead to changes in the microstructural properties. Microstructure plays a very crucial role in determining the mechanical property of the irradiated region, thus determining the optimum laser processing conditions. In this study, metallographic studies, as well as tensile, fatigue and hardness tests, are undertaken on SUS430/C11000/SUS430 laminated composites that have been exposed to laser irradiation with different number of passes. This composite can be used in the microelectronics industry since it has the anti-corrosion and strength capability of stainless steel, and the electrical superiority of copper. Ytterbium fiber laser is used in such a way that the governing mechanism of the process is the temperature gradient mechanism. Evolution of the microstructure is revealed by metallography, and the fracture levels of tension and fatigue test specimens are further evaluated by SEM. This study illustrates the significant effects of successive laser irradiation on the evolution of microstructure and mechanical properties, which lead to some suggestions for improving the properties of laser-formed SUS430/C11000/SUS430 composites.

On the detachment of thin ITO films from silicon substrate by microsecond laser irradiation

A method for the separation of thin ITO (indium-tin-oxide) films from a silicon substrate by pulsed laser irradiation is studied. The method enables the detachment of films with thicknesses of 360 nm and more without their destruction. The separation process consists in successive irradiation of the surface with single microsecond laser pulses at a wavelength of 650 nm. Upon being detached from silicon substrates, the films produced by high-frequency magnetron sputtering have a transmittance of 65% in the visible spectral range and a resistivity of ~1.2 kΩ/□. The thermal stresses appearing in thin ITO films and leading to their detachment are estimated.

Photochemically Controlled Drug Dosing from a Polymeric Scaffold

PurposeTo develop the first photoactive biomaterial coating capable of controlled drug dosing via inclusion of synthesised drug-3,5-dimethoxybenzoin (DMB) conjugates in a poly(2-methyoxyethyl acrylate) (pMEA) scaffold.MethodsFlurbiprofen- and naproxen-DMB conjugates were prepared via esterification and characterised via NMR spectroscopy and mass spectrometry following chromatographic purification. Conjugate photolysis was investigated in acetonitrile solution and within the pMEA matrix following exposure to low-power 365 nm irradiation. Photo-liberation of drug from pMEA into phosphate buffered saline was monitored using UV-vis spectroscopy.ResultsThe synthetic procedures yielded the desired drug conjugates with full supporting characterisation. Drug regeneration through photolysis of the synthesised conjugates was successful in both acetonitrile solution and within the pMEA scaffold upon UV irradiation. Conjugates were retained within the pMEA scaffold with exclusive drug liberation following irradiation and increased drug dose with increasing exposure. Multi-dosing capacity was demonstrated though the ability of successive irradiation periods to generate further bursts of drug.ConclusionThis study demonstrates the first application of photochemically controlled drug release from a biomaterial coating and the feasibility of using pMEA as a scaffold for housing the photoactive drug-DMB conjugates.

Facile Synthetic Route to a Nitrogen‐doped Titanium Oxide with Enhanced Photoelectrochemical Property via Proton Beam Irradiation

A layered titanate with a light harvesting property only in a UV region was irradiated with a proton beam in the presence of nitrogen source like ammonium cation, in order to modify its band gap from UV to visible region. According to X‐ray diffraction and X‐ray absorption spectroscopy results, a protonic titanate maintains its lamellar structure even after proton beam bombardment, showing that the crystal structure of layered titanate was preserved even after the ammonium adsorption and successive proton beam irradiation for nitrogen doping. However, UV–vis and X‐ray photoelectron spectra clearly show that the proton beam irradiation could provide enough energy to introduce ~0.5 at. % of nitrogen atoms into the titanium oxide for absorbing not only UV but also visible light. Photocurrent measurement clearly reveals that the nitrogen‐doped titanium oxide via the proton beam treatment shows highly enhanced photocurrent in comparison with that of the bare titanium oxide, suggesting that the proton beam irradiation could be a potential method for band gap engineering of a wide variety of semiconducting materials.

Enhanced superconductivity, Kondo behavior, and negative-curvature resistivity of oxygen-irradiated thin films of aluminium

We followed the evolution of the normal and superconducting properties of Al thin films after each session of various successive oxygen irradiations at ambient temperature. Such irradiated films, similar to the granular ones, exhibit enhanced superconductivity, Kondo behavior and negative-curvature resistivity. Two distinct roles of oxygen are identified: as a damage-causing projectile and as an implanted oxidizing agent. The former gives rise to the processes involved in the conventional recovery stages. The latter, considered within the context of the Cabrera-Mott model, gives rise to a multistep process which involves charges transfer and creation of stabilized vacancies and charged defects. Based on the outcome of this multistep process, we consider (i) the negative curvature resistivity as a manifestation of a thermally-assisted liberation of trapped electric charges, (ii) the Kondo contribution as a spin-flip scattering from paramagnetic, color-center-type defects, and (iii) the enhancement of T_{c} as being due to a lattice softening facilitated by the stabilized defects and vacancies. The similarity in the phase diagrams of granular and irradiated films as well as the aging effects are discussed along the same line of reasoning.

Influence of dose history on thermoluminescence response of Ge-doped silica optical fibre dosimeters

Nowadays, silica based optical fibres show enough potential to be used as TL dosimeters in different applications. Reuse of optical fibre as a practical dosimeter demands to complete removal of accumulated doses via previous irradiations. This work investigates the existence and/or effect of remnant doses in fibre dosimeter from the previous irradiations, and proposes a method to control this artifact. A single mode Ge-doped optical fibre is used as TL radiation sensor, while a well calibrated Gammacell with 60Co source is used for irradiations. The effect of irradiation history on the TL response of optical fibres is surveyed extensively for doses ranged from 1 to 1000Gy. The results show that the absorbed dose history in a fibre affects its response in the next irradiation cycles. It is shown that a dose history of around 100Gy can increase the response of optical fibre by a factor of 1.72. The effect of annealing at higher temperatures on stabilizing the fibre response is also examined and results revealed that another alteration in the structure of trapping states occurs in glass medium which can change the sensitivity of fibres. Preservation of the sensitivity during successive irradiation cycles can be achieved by a proper annealing procedure accompanied by a pre-dose treatment.

Optical study of gamma irradiated sodium metaphosphate glasses containing divalent metal oxide MO (ZnO or CdO)

Sodium metaphosphate glasses containing divalent metal oxide, ZnO or CdO with composition 50 P2O5 – (50−x) Na2O – x MO (ZnO, or CdO) where x=0, 10, 20 (mol%) were prepared by conventional melt method. UV/visible spectroscopy and FTIR spectroscopy are measured before and after exposing to successive gamma irradiation doses (5–80kGy). The optical absorption spectra results of the samples before irradiation reveal a strong UV absorption band at (∼230nm) which is related to unavoided iron impurities. The effects of gamma irradiation on the optical spectral properties of the various glasses have been compared. From the optical absorption spectral data, the optical band gap is evaluated. The main structural groups and the influence of both divalent metal oxide and gamma irradiation effect on the structural vibrational groups are realized through IR spectroscopy. The FTIR spectra of γ-irradiated samples are characterized by the stability of the number and position for the main characteristic band of phosphate groups. To better understood the structural changes during γ-irradiation, a deconvolution of FTIR spectra in the range 650–1450cm−1 is made. The FTIR deconvolution results found evidence that, the changes occurring after gamma irradiation have been related to irradiation induced structural defects and compositional changes.

CO2 laser microprocessing for laser damage growth mitigation of fused silica optics

We report on the development of a mitigation process to prevent the growth of UV nanosecond laser-initiated damage sites under successive irradiations of fused silica components. The developed process is based on fast microablation of silica as it has been proposed by Bass et al. [Bass et al., Proc. SPIE 7842, 784220 (2010)]. This is accomplished by the displacement of the CO2 laser spot with a fast galvanometer beam scanner to form a crater with a typical conical shape to mitigate large (millimetric) and deep (few hundred microns) damage sites. We present the developed experimental system and process for this application. Particularly, we detail and evaluate a method based on quantitative phase imaging to obtain fast and accurate three-dimensional topographies of the craters. The morphologies obtained through different processes are then studied. Mitigation of submillimetric nanosecond damage sites is demonstrated through different examples. Experimental and numerical studies of the downstream intensifications, resulting in cone formation on the surface, are presented to evaluate and minimize the downstream intensifications. Eventually, the laser damage test resistance of the mitigated sites is evaluated at 355, 2.5 ns, and we discuss on the efficiency of the process for our application.