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The objective of this study is to analyze the effects of using surfactant (CTAB) and cellulose nanofibers (NFC) as an admixture in cement mortars. We examined composite properties as porosity, compression energy, thermal conductivity and hydration. The results showed that with the addition of 0.7% by weight of NFC per emulsion in the presence of a cationic surfactant (CTAB). The new material produced presented a dry porosity between 4.7% and 4.4%, compressive strength between 9.8 and 22.9 MPa, and thermal conductivity between 0.95 and 2.25 W·m-1·K-1. Thus we show better mechanical and thermal performance than that traditional Portland cement mortar with a density similar. In addition, the mortar made by emulsion of ordinary portland cement, cellulose nanofiber and organophilic clay (OC) treated with cetyltrimethylammonium bromide (CTAB) obtained has good resistance under high temperature and water, as well as excellent thermal insulation performance under high temperature and humidity conditions. This study verified that the presence of NFC promotes hydration, leading to the production of more calcium silicate and portlandite gel. [ABSTRACT FROM AUTHOR]

Neutron, gamma-ray, and x-ray imaging are important diagnostic tools at the National Ignition Facility (NIF) for measuring the two-dimensional (2D) size and shape of the neutron producing region, for probing the remaining ablator and measuring the extent of the DT plasmas during the stagnation phase of Inertial Confinement Fusion implosions. Due to the difficulty and expense of building these imagers, at most only a few two-dimensional projections images will be available to reconstruct the three-dimensional (3D) sources. In this paper, we present a technique that has been developed for the 3D reconstruction of neutron, gamma-ray, and x-ray sources from a minimal number of 2D projections using spherical harmonics decomposition. We present the detailed algorithms used for this characterization and the results of reconstructed sources from experimental neutron and x-ray data collected at OMEGA and NIF. [ABSTRACT FROM AUTHOR]

The formation of a new compound with stoichiometry As4O6·2He at relatively low pressure (3 GPa) has been recently reported when arsenolite (As4O6) powder is compressed with helium as a pressure-transmitting medium. In this work, we study the lattice dynamics of As4O6 and As4O6·2He at high pressures from an experimental and theoretical perspective by means of Raman scattering measurements and ab initio calculations and report the theoretical elastic properties of both compounds at high pressure. Raman scattering measurements show a completely different behaviour of As4O6 and As4O6·2He at high pressures. Furthermore, the theoretical calculation of phonon dispersion curves and elastic stiffness coefficients at high pressure in both compounds allow us to discuss their dynamical and mechanical stability under hydrostatic compression. Both compounds are dynamically stable even above 35 GPa, but As4O6 becomes mechanically unstable at pressures beyond 19.7 GPa. These results allow explaining the pressure-induced amorphization of As4O6 found experimentally above 15-20 GPa and the lack of observation of any instability in As4O6·2He up to the highest studied pressure (30 GPa). [ABSTRACT FROM AUTHOR]

The Seebeck coefficient is the most widely measured property specific to thermoelectric materials. There is currently no consensus on measurement protocols, and researchers employ a variety of techniques to measure the Seebeck coefficient. The implementation of standardized measurement protocols and the use of reliable Seebeck Coefficient Standard Reference Materials (SRMs® ) will allow the accurate interlaboratory comparison and validation of materials data, thereby accelerating the development and commercialization of more efficient thermoelectric materials and devices. To enable members of the thermoelectric materials community the means to calibrate Seebeck coefficient measurement equipment, NIST certified SRM® 3451 "Low Temperature Seebeck Coefficient Standard (10K to 390 K)". Due to different practical requirements in instrumentation, sample contact methodology, and thermal stability, a complementary SRM® is required for the high temperature regime (300K to 900 K). The principal requirement of a SRM® for the Seebeck coefficient at high temperature is thermocyclic stability. We therefore characterized the thermocyclic behavior of the Seebeck coefficient for a series of candidate materials: constantan, p-type single crystal SiGe, and p-type polycrystalline SiGe, by measuring the temperature dependence of the Seebeck coefficient as a function of 10 sequential thermal cycles, between 300K and 900 K. We employed multiple regression analysis to interpolate and analyze the thermocyclic variability in the measurement curves. © 2014 AIP Publishing LLC. [ABSTRACT FROM AUTHOR]

Self-atom mixing induced by 310 keV gallium (Ga) ion implantation in crystalline and preamorphized germanium (Ge) at temperatures between 164 K and 623 K and a dose of 1 x 1015cm² is investigated using isotopic multilayer structures of alternating 70Ge and natGe layers grown by molecular beam epitaxy. The distribution of the implanted Ga atoms and the ion-beam induced depth-dependent self-atom mixing was determined by means of secondary ion mass spectrometry. Three different temperature regimes of self-atom mixing, i.e., low-, intermediate-, and high-temperature regimes are observed. At temperatures up to 423 K, the mixing is independent of the initial structure, whereas at 523 K, the intermixing of the preamorphized Ge structure is about twice as high as that of crystalline Ge. At 623 K, the intermixing of the initially amorphous Ge structure is strongly reduced and approaches the mixing of the crystalline material. The temperature dependence of ion-beam mixing is described by competitive amorphization and recrystallization processes. [ABSTRACT FROM AUTHOR]

Sensor technologies that can operate under extreme conditions including high temperatures, high pressures, highly reducing and oxidizing environments, and corrosive gases are needed for process monitoring and control in advanced fossil energy applications. Sensor technologies based on optical waveguide-based techniques are highly attractive for passive, embedded, and remote sensing. A critical enabling technology for optical waveguide sensors is the development of advanced optical thin film coatings which have a desired set of optical properties that change in a rapid, selective, and sensitive manner to a particular quantity of interest. TiO2 and Au nanoparticle incorporated TiO2 nanocomposite thin films were prepared through sol-gel deposition techniques and their respective optical responses to a 4% H2/N2 mixture were investigated in the visible / near-IR range of 400-1000 nm. A tendency for Au nanoparticles to occupy special sites on the TiO2 microstructure, such as grain boundaries, twin boundaries, and triple points is rationalized in terms of basic surface energy arguments. The Au / TiO2 nanocomposite films showed a useful optical response due to a reversible, rapid, and repeatable shift in the localized surface plasma resonance peak of Au nanoparticles at a temperature of 650 °C and 850 °C. In contrast, high temperature exposure of TiO2 films to reducing gases at 850 °C resulted in the growth of abnormally large grains or 'hillocks' that protruded from the sample surface and resulted in light scattering and an irreversible decrease in transmission at short wavelengths. The origin of the observed optical response of Au / TiO2 nanocomposite films is discussed in the context of work by prior investigators in the Au / yttria-stabilized Zirconia (YSZ) system and needs for future research in this area is highlighted. [ABSTRACT FROM AUTHOR]

The high-temperature ferroelectric behaviors for poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)) copolymer ultrathin films with electroactive interlayers have been studied. The different electroactive polymers, commercial poly(3,4-ethylene dioxythiophene)-poly(styrene sulfonic) acid (PEDOT-PSSH), in situ synthesized PEDOT-PSSH with high PEDOT ratio and poly(3,4-ethylene dioxythiophene)-poly(styrene sulfonic) ammonia (PEDOT-PSSNH4), are used as the interlayer between P(VDF-TrFE) and metal electrodes. It is found that the ferroelectric properties at high temperature are strongly dependent on the interlayer and the faster degradation occurs on the sample with the interlayer which has enough protons as compensating charges. Further analysis on the polarization response behaviors and capacitance shows that the high-temperature ferroelectric properties are more closely associated with the compensating charges in interlayer than the ferroelectric film itself, illustrating the importance of the appropriate interlayer materials. [ABSTRACT FROM AUTHOR]

The electrical conduction mechanisms contributing to the leakage current at different field regions and different temperatures have been studied in this work. The current-voltage (I-V) measurement of TiN/HfO2/SiO2/P-Si nMOS capacitor in the temperature range from 25 °C to 125 °C, taken before stressing and in the temperature range of 25 °C to 65 °C after constant voltage stressing (CVS) at 3 V suggests that the Poole-Frenkel mechanism is the dominant conduction mechanism in the high field region. It was also observed that in the low electric field region Ohmic conduction is the dominant mechanism. Trap energy level (φt) of 0.36 eV, obtained from the Poole-Frenkel mechanism indicates that the defect is oxygen-related and is a good match with the reported value for V-/V-- in HfO2. Significant charge trapping at low level stress was observed whereas at high level and elevated temperature stressing suggests a variation of trap energy level indicating new defect formation. It is observed that the stress induced gate leakage current for the high temperature stressed devices is about three orders of magnitude more than that of room temperature stressed devices for the whole field range. [ABSTRACT FROM AUTHOR]

Atomistic Green-Kubo simulations are performed to evaluate the lattice thermal conductivity for single crystals of the ultra high temperature ceramics ZrB2 and HfB2. Recently developed interatomic potentials are used for these simulations. Heat current correlation functions show rapid oscillations, which can be identified with mixed metal-Boron optical phonon modes. Results for temperatures from 300K to 1000K are presented. [ABSTRACT FROM AUTHOR]

We report the appearance of two plastic crystal phases of water at high pressure and temperature using computer simulations. In one of them the oxygen atoms form a body centered cubic structure (bcc) and in the other they form a face centered cubic structure (fcc). In both cases the water molecules were able to rotate almost freely. We have found that the bcc plastic crystal transformed into a fcc plastic crystal via a Martensitic phase transition when heated at constant pressure. We have performed the characterization and localization in the phase diagram of these plastic crystal phases for the SPC/E, TIP4P, and TIP4P/2005 water potential models. For TIP4P/2005 model free energy calculations were carried out for the bcc plastic crystal and fcc plastic crystal using a new method (which is a slight variation of the Einstein crystal method) proposed for these types of solid. The initial coexistence points for the SPC/E and TIP4P models were obtained using Hamiltonian Gibbs–Duhem integration. For all of these models these two plastic crystal phases appear in the high pressure and temperature region of the phase diagram. It would be of interest to study if such plastic crystal phases do indeed exist for real water. This would shed some light on the question of whether these models can describe satisfactorily the high pressure part of the phase diagram of water, and if not, where and why they fail. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to present a local stability analysis of an endoreversible heat pump operating at the minimum input power P for given heating load qH to the high-temperature reservoir, for different thermal conductances α and β, in the isothermal couplings of the working fluid with the heat reservoirs TH and TL(TH>TL). An endoreversible heat pump system that is modeled by the differential equation may depend on the numerical values of certain parameters that appear in the equation. From the local stability analysis we find that a critical point of an almost linear system is a stable node. After a small perturbation the system state exponentially decays to steady state with either of two relaxation times that are a function of α, β, qH, TH, and the heat capacity C. We can exhibit qualitatively the behavior of solutions of the system by sketching its phase portrait. One eigenvector in a phase portrait is the nonzero constant vector, and the other is a function of α, β, qH, TH, and TL. Finally, we discuss the local stability and energetic properties of the endoreversible heat pump. [ABSTRACT FROM AUTHOR]

Recent studies have predicted that heterostructure superlattices can enhance the effective thermoelectric power factor significantly through selective emission of hot carriers via thermionic emission. Here, we study the potential of SiGe/Si superlattices for power generation at high temperatures. A detailed theory based on Boltzmann transport equation is developed which takes into account multiple valleys. We show that thermionic emission provides only a modest improvement in the power factor. This is due to the fact that SiGe is a multivalley semiconductor and it has a large density of states. With reasonable dopings, Fermi energy in SiGe alloy is very close to the band minimum so that the symmetry of the differential conductivity does not change very much with small barrier superlattices. Particularly at high temperatures when the thermal spread of the carriers is much larger than the Fermi energy in the band, superlattice energy filtering is not effective. [ABSTRACT FROM AUTHOR]

LaNiO3 thin films have been deposited on SrTiO3 (100) by pulsed laser deposition. Substrate temperature and oxygen pressure have been investigated in the ranges of 640–840 °C and 200–600 μbars, respectively. The use of LaNiO3 as an electrode requires good electrical, structural, and morphological properties. Optimized deposition parameters were determined to be in the range from 650 to 700 °C for the substrate temperature and in the oxygen pressure range from 300 to 400 μbars. Spectroscopic ellipsometry has been used to study in situ the growth of LaNiO3 at high temperature and variation of the optical constants during the cooling from growth to ambient temperature. The metallic behavior of the LaNiO3 is directly observed from the spectral variation of the ellipsometric parameters, tan Ψ and cos Δ. For the initial stages of the film growth a determination of the thickness by ellipsometry is possible until the skin depth is reached. The optical constants, refractive index n and extinction coefficient k, have been calculated using a simple model of reflection for the light from a semi-infinite metal during the thermal variation. A linear decrease of the optical constants with a change in curve slope is observed in the temperature interval from 240 to 400 °C. Analysis of the ellipsometric parameters using a Drude-Lorentz dispersion relation indicates a modification in the free electron behavior at high temperatures. [ABSTRACT FROM AUTHOR]

LaNiO3 thin films have been deposited on SrTiO3 (100) by pulsed laser deposition. Substrate temperature and oxygen pressure have been investigated in the ranges of 640–840 °C and 200–600 μbars, respectively. The use of LaNiO3 as an electrode requires good electrical, structural, and morphological properties. Optimized deposition parameters were determined to be in the range from 650 to 700 °C for the substrate temperature and in the oxygen pressure range from 300 to 400 μbars. Spectroscopic ellipsometry has been used to study in situ the growth of LaNiO3 at high temperature and variation of the optical constants during the cooling from growth to ambient temperature. The metallic behavior of the LaNiO3 is directly observed from the spectral variation of the ellipsometric parameters, tan Ψ and cos Δ. For the initial stages of the film growth a determination of the thickness by ellipsometry is possible until the skin depth is reached. The optical constants, refractive index n and extinction coefficient k, have been calculated using a simple model of reflection for the light from a semi-infinite metal during the thermal variation. A linear decrease of the optical constants with a change in curve slope is observed in the temperature interval from 240 to 400 °C. Analysis of the ellipsometric parameters using a Drude-Lorentz dispersion relation indicates a modification in the free electron behavior at high temperatures. [ABSTRACT FROM AUTHOR]

We investigated the stability of a uniform and stoichiometric 0.6-nm-thick A1[sub 2]O[sub 3] film on a Si(001) surface during high-temperature annealing in ultrahigh vacuum (UHV), under low oxygen pressure (2 × 10[sup -6], 5 × 10[sup -6] and 2 × 10[sup -5] Torr O[sub 2]), and under high oxygen pressure (5 × 10[sup -5] Torr O[sub 2]) conditions. UHV annealing of the Al[sub 2]O[sub 3]/Si(001) system at 900°C drastically degraded the A1[sub 2]O[sub 3] film quality and caused atomic-scale roughness at the A1[sub 2]O[sub 3]/Si(001) interface. Voids formed in the oxide film as annealing progressed. A low oxygen pressure ambient during annealing, while more or less maintaining the film stoichiometry, caused atomic-scale roughness at the interface. A high oxygen pressure ambient during annealing maintained the film stoichiometry and thickness. However, this processing condition led to the formation of interfacial Si oxide, which caused substantial SiO volatilization and etching of the Si substrate at the A1[sub 2]O[sub 3]/Si(001) interface, thereby inducing nanometer-scale roughness at the interface. These results indicate that high-temperature processing imposes a limitation in controlling the composition of ultrathin Al[sub 2]O[sub 3] films and maintaining the abruptness of the A1[sub 2]O[sub 3]/Si(001) interface on an atomic scale. [ABSTRACT FROM AUTHOR]

Abstract A series of TC4/ZrB 2 nanomultilayers with different modulation periods (Λ) were fabricated on the Si substrate by the magnetron sputtering technique. The results indicated that all the multilayers showed a lower crystallization at the lower Λ values ranging from 15 to 40 nm and presented the structure of mixed layer/amorphous layer/crystallization layer. Owing to the enhancement of crystallinity of ZrB 2 that prevented grain-boundary sliding, the highest hardness (24.81 GPa) and elastic modulus (283.70 GPa) values were realized at Λ of 40 nm. The lowest surface roughness (R a = 0.332 nm) were obtained at Λ of 20 nm. The smaller grain size at the lower Λ should be one of the main contributions to the improved mechanical properties. As the crystal layers were covered by mixed layers and amorphous layers, the multilayers also exhibited excellent thermal stability. High temperature annealing experiments showed that the multilayers maintain good microstructure and the hardness slightly increased after annealed at 600 °C. Therefore, the existence of the amorphous layer is favorable for buffering high temperature damage to the interface of the multilayers, resulting in an increase in the high temperature stability of the multilayers. Highlights • Nanoscale TC4/ZrB 2 multilayers were prepared by magnetron sputtering. • Multilayers with different mechanical properties have been prepared by controlling Λ. • The highest H (24.81 GPa) and E (283.70 GPa) values were realized at λ of 40 nm. • The properties of the multilayer remain stable after annealing. • The three layers structure of multilayer film. [ABSTRACT FROM AUTHOR]

• We study the effects of randomly distributed He bubbles on the spall damage in single crystal aluminum under decaying shock loadings. • He bubble plays important role in the dynamic properties, including the spall damage mechanism and characteristics. • The mechanism of spall damage is dominated by He bubble expansion-merging-absorption, followed by void nucleation-growth-coalescence. • The spall strength of Al in solid state is reduced by He bubble, but this effect becomes negligible when the crystal is melted. The mechanism and characteristics of spall damage in single crystal Al with randomly distributed helium bubbles under decaying shock loading are studied by molecular dynamics simulations. We find that He bubble plays important role in the dynamic process. The mechanism of spall damage is dominated by He bubble expansion-merging-absorption, followed by void nucleation-growth-coalescence. During spalling process, He bubbles impede the nucleation of surrounding voids, they expand at a higher rate than that for void growth, adjacent He bubbles merge together, and small voids are absorbed by nearby large He bubble. These behaviors finally lead to a very different morphology of the damaged zone from that for the perfect crystal, whose spall damage mechanism is void nucleation-growth-coalescence. Obvious differences in temperature profile are observed between the crystal with He bubbles and the perfect crystal because the compression of surrounding atoms induced by He bubble expansion results in higher local temperature, especially in solid state. In melted state, the contribution of He bubbles becomes comparatively small since more voids are nucleated followed by faster voids growth and coalescence that lead to higher temperature rising. Additionally, He bubble significantly reduces the spall strength of Al in solid state, but this effect becomes negligible when the crystal is melted. [ABSTRACT FROM AUTHOR]

Type 316LN stainless steel (SS) is the principal structural material for the components of sodium cooled fast reactors operating under elevated temperature conditions. In order to assess the degradation in strength of service exposed components using a small specimen testing technique such as automated ball indentation (ABI), it is necessary to carry out prior detailed ABI studies on the virgin material. In this investigation, the tensile behaviour of as-received 316LN SS were investigated at several temperatures in the range 298-973 K using ABI technique. The load-depth of indentation data measured from ABI tests was analyzed using semi-empirical relationships to obtain the tensile properties. The yield stress and the flow curves were determined by correlating ABI results with corresponding uniaxial tensile test results. Trend curve for tensile strength with temperature, as estimated from ABI tests, exhibited a plateau region in the temperature around 823 K, similar to uniaxial tensile tests. The variations of strength coefficient, strain hardening exponent, yield ratio, hardness and uniform ductility with temperature were evaluated from ABI tests. The ABI technique was found to estimate the influence of temperature on tensile properties sensitively. [ABSTRACT FROM AUTHOR]

Successful integration of carrier selective contacts (so-called passivated contacts) in p -type and n -type front-and-back contact (FAB) silicon solar cells could lift cell efficiencies to above 24% in mass production. In this work, we introduce one of SERIS’ monoPoly FAB cell structures, which features the monofacial (single-sided) application of a polysilicon (poly-Si) layer. Using industrial tools, doped poly-Si on an ultrathin interface oxide is shown to provide extremely low recombination current density of 4 fA/cm 2 and implied open-circuit voltage of about 745 mV that are able to withstand the high-temperature firing process of screen-printed metal contacts. The interface oxide and the doping concentration of the poly-Si film are of great importance for the surface passivation quality and the transport of majority carriers, especially for fire-through screen-printed contacts as used in this work. Our initial pilot-line results show a very promising cell efficiency of 21.4% on large-area (244.3 cm 2 ) n -type monocrystalline wafers with screen-printed and fire-through metal contacts on both sides. A roadmap for n FAB monoPoly cells towards 24% efficiency is presented on the basis of an optimisation of the device architecture and various processing steps. [ABSTRACT FROM AUTHOR]

Abstract Due to the high material utilization and the associated resource and energy efficiency, production processes from the field of cold forging of steel are of great importance. At present, environmentally harmful lubricants have to be used to ensure process stability as well as low wear and friction. Due to environmental, economic and legislative aspects, there is an increased research potential to reduce or to completely substitute lubricants. To achieve the goal of lubricant free dry cold forging of steel, physical vapor deposition (PVD) coatings with self-lubricating properties are applied on forming tools. Promising for this application are PVD coatings on the basis of a (Cr,Al)N hard phase with embedded molybdenum and sulfur which simultaneously meet the requirements of high wear resistance and friction reduction. In the presented work, three self-lubricating coatings (Cr,Al)N+Mo:S deposited with varying bias voltage were investigated. The hybrid PVD technology, consisting of direct current and high power pulse magnetron sputtering dcMS/HPPMS, was used for the coating deposition in an industrial coating unit. Two different steels AISI D2 (DIN 1.2379) and AISI M2 (DIN 1.3343) were used as substrate materials. The influences of substrate material and heat treatments at T = 250 °C were investigated. The samples were analyzed with respect to the universal hardness HU and modulus of indentation E IT using nanoindentation. To determine the interfacial adhesion of the compound coating/substrate, Rockwell indentation and scratch tests were carried out. For the analysis of the tribological behavior, unhardened AISI 5115 (DIN 1.7131) was used as counterpart material. The influence of the elevated temperature on the friction and wear behavior was investigated by Pin-on Disk (PoD) at T = 250 °C and T = 23 °C. The wear of the basic bodies as well as the counterparts were analyzed by confocal laserscanning microscopy. The investigations have shown that the high temperature has a significant influence on the friction and wear behavior. The wear rate of the counterparts decreases by up to a factor greater than x = 100 compared to the test at T = 23 °C. Furthermore, the wear rates of the basic body of the uncoated reference specimen increase rapidly at tribological stress at high temperatures. The examined coatings exhibit high wear resistance at elevated temperatures. The contact surface was studied by Raman spectroscopy after the tribological tests. PoD tests have shown, that the applied coatings led to a significantly reduction in friction most likely due to the tribo-chemically induced formation of self-lubricating MoS 2 reaction layers. Highlights • Hybrid dcMS/HPPMS deposition of (Cr,Al)N+Mo:S coatings with varying bias voltage • Sulfur content as a function of bias voltage due to resputtering effects • Improved friction and wear behavior due to self-lubricating PVD coatings • Formation of tribo-chemically induced reaction layers • Tribo-oxidation in sliding contacts at varying temperatures [ABSTRACT FROM AUTHOR]

Despite frequent reports of liquid metal embrittlement (LME) during resistance spot welding, no work has been done to investigate the LME sensitivity in laser beam welding (LBW) of advanced high strength steels. The present study was therefore undertaken to reflect the LME sensitivity of Zn-coated 22MnB5 press-hardening steel as a function of stress intensity and heat input during LBW. The results proved a direct relation between the external load and LME susceptibility, where the threshold tensile stress of about 80%YS is necessary to trigger the embrittlement. Electron backscatter diffraction (EBSD) in conjunction with electron probe micro-analyzer (EPMA) results confirmed the intergranular penetration of Zn along the prior austenite high-angle grain boundaries in upper-critical heat affected zone (UCHAZ). The presence of Zn over the maximum Zn-solubility of austenite promotes α-Fe(Zn) transformation along the LME-crack which assists the loss of ductility. The present findings provide an understanding of the mechanism of embrittlement in UCHAZ and suggest solutions to mitigate the LME in LBW of boron steels. [ABSTRACT FROM AUTHOR]

Presents a study which examined the isothermal annealing of electron-irradiated Czochralski silicon samples using deep-level transient spectroscopy and photoluminescence. Background on Czochralski silicon; Experimental setup; Results and conclusions.

Presents information on a study that investigated the formation of defects accompanied by a reduction in the concentration of oxygen interstitials in the prolonged annealing of Czochralski silicon at 485 degrees centigrade using high-resolution electron microscopy. Methodology of the study; Results and discussion on the study.

Presents information on a study that examined (Ba[sub0.7]Pb[sub0.3])TiO[sub3] materials possessing double critical temperature in resistivity-temperature behavior by microwave sintering. Methodology of the study; Results and discussion on the study; Conclusion.

Focuses on a study which developed a computational model to optimize the design of a surface reflection neutralization source of hyperthermal neutrals for charge-free processing. Theoretical background; Methodology; Findings.