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At least 217 records · Page 12

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DOE OSTI2018

Porous carbon nanofiber derived from a waste biomass as anode material in lithium-ion batteries

In this paper the entire process chain from raw biomass to carbon nanofiber (CNF) to high functioning lithium ion batteries (LIB) have been followed to evaluate the use of renewable materials for components of energy storage device. Electrospun CNF was prepared from a waste walnut shells using a relatively simple procedure for liquefying, electrospinning and carbonizing the fibrils. Mats of these CNF were used in LIB without binder, and the performance was measured as a function of the parameters used to prepare the nanofibers. Electrospinning solutions to polyvinyl alcohol at mass ratio of 80/20, 70/30 to 60/40 and carbonization temperature in the range from 800, 1000 to 1200 degrees C were used and the morphology, structure properties, and specific surface area of the walnut shell-derived carbon nanofiber (CNF) were comprehensively characterized. Their electrochemical performance were also investigated as electrode materials in LIB. The electrode obtained at 800 degrees C with mass ratio of 80/20 shows the highest specific capacity of 380 mA h g -1 at 0.03 A g -1 with an initial efficiency of 55.89%, and presents excellent cycling performance and high degree of reversibility (above 280 mA h g -1 specific capacity after 200 cycles at 0.1 A g -1 ).

25 ENERGY STORAGE↗

DOE OSTI2013

Silver nanocrystals of various morphologies deposited on silicon wafer and their applications in ultrasensitive surface-enhanced Raman scattering

Silver nanostructures with dendritic, flower-like and irregular morphologies were controllably deposited on a silicon substrate in an aqueous hydrogen fluoride solution at room temperature. The morphology of the Ag nanostructures changed from dendritic to urchin-like, flowerlike and pinecone-like with increasing the concentration of polyvinyl pyrrolidone (MW = 55,000) from 2 to 10 mM. The Ag nanostructures were characterized by transmission electron microscopy, high-resolution transmission electron microscopy, scanning electron microscopy, energy-dispersive X-ray, and X-ray diffraction. Through a series of time-dependent morphological evolution studies, the growth processes of Ag nanostructures have been systematically investigated and the corresponding growth mechanisms have been discussed. In addition, the morphology-dependent surface-enhanced Raman scattering of as-synthesized Ag nanostructures were investigated. The results indicated that flower-like Ag nanostructure had the highest activity than the other Ag nanostructures for Rhodamine 6G probe molecules. Highlights: • A simple method was developed to prepare dendritic and flower-like Ag nanostructures. • The flower-like Ag nanoparticles exhibit highest SERS activity. • The SERS substrate based on flower-like Ag particles can be used to detect melamine.

36 MATERIALS SCIENCE↗

DOE OSTI2014

Electrospinning of nickel oxide nanofibers: Process parameters and morphology control

In the present work, nickel oxide nanofibers with varying morphology (diameter and roughness) were fabricated via electrospinning technique using a precursor composed of nickel acetate and polyvinyl alcohol. It was found that the diameter and surface roughness of individual nickel oxide nanofibers are strongly dependent upon nickel acetate concentration in the precursor. With increasing nickel acetate concentration, the diameter of nanofibers increased and the roughness decreased. An optimum concentration of nickel acetate in the precursor resulted in the formation of smooth and continuous nickel oxide nanofibers whose diameter can be further controlled via electrospinning voltage. Beyond an optimum concentration of nickel acetate, the resulting nanofibers were found to be ‘flattened’ and ‘wavy’ with occasional cracking across their length. Transmission electron microscopy analysis revealed that the obtained nanofibers are polycrystalline in nature. These nickel oxide nanofibers with varying morphology have potential applications in various engineering domains. - Highlights: • Nickel oxide nanofibers were synthesized via electrospinning. • Fiber diameter and roughness depend on nickel acetate concentration used. • With increasing nickel acetate concentration the roughness of nanofibers decreased. • XRD and TEM revealed a polycrystalline structure of the nanofibers.

36 MATERIALS SCIENCE↗

DOE OSTI2011

Electrodeposited ZnO films with high UV emission properties

Highlights: {yields} Electrodeposition of ZnO from nitrate baths is investigated. {yields} The influence of process parameters on morphological and optical properties is studied. {yields} Experimental conditions to fabricate ZnO films with high UV emission were found. -- Abstract: We report here our results in the preparation of ZnO films with high UV band to band characteristic luminescence emission by potentiostatic electrodeposition. Zinc nitrate aqueous baths with different concentration and additives were employed for the preparation of the films on platinum substrates. We focused our research in determining how the electrodeposition bath composition, i.e. zinc nitrate concentration and addition of KCl or polyvinyl pyrolidone and applied overpotential influence the morphological and optical properties of the oxide films. Scanning electron microscopy was employed for characterizing the films in terms of morphology. Optical reflection, photoluminescence spectroscopy and cathodoluminescence were used for determining the optical characteristics of the samples. The morphology of the deposit varies from hexagonal prisms to platelets as a function of the deposition rate. This experimental parameter also influences the luminescence properties. We found that at low deposition rates high UV luminescent material is obtained.

36 MATERIALS SCIENCE↗

DOE OSTI2013

Nickel nanofibers synthesized by the electrospinning method

Highlights: ► The nickel nanofibers have been obtained by electrospinning method. ► The nickel nanofibers had rough surface which was consisted of mass nanoparticles. ► The average diameter of nickel nanofibers is about 135 nm and high degree of crystallization. ► The Hc, Ms, and Mr were estimated to be 185 Oe, 51.9 and 16.9 emu/g respectively. - Abstract: In this paper, nickel nanofibers were prepared by electrospinning polyvinyl alcohol/nickel nitrate precursor solution followed by high temperature calcination in air and deoxidation in hydrogen atmosphere. The thermal stability of the as-electrospun PVA/Ni(NO{sub 3}){sub 2} composite nanofibers were characterized by TG–DSC. The morphologies and structures of the as-prepared samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field-emission scanning electronmicroscope (FE-SEM) and field-emission transmission electron microscopy (FE-TEM). The hysteresis loops (M–H loops) were measured by Physical Property Measurement System (PPMS). The results indicate that: the PVA and the nickel nitrate were almost completely decomposed at 460 °C and the products were pure nickel nanofibers with face-centered cubic (fcc) structure. Furthermore, the as-prepared nickel nanofibers had a continuous structure with rough surface and high degree of crystallization. The average diameter of nickel nanofibers was about 135 nm. The nanofibers showed a stronger coercivity of 185 Oe than value of bulk nickel.

36 MATERIALS SCIENCE↗

DOE OSTI2013

Hydrothermal synthesis of Mn vanadate nanosheets and visible-light photocatalytic performance for the degradation of methyl blue

Graphical abstract: - Highlights: • Mn vanadate nanosheets have been synthesized by simple hydrothermal process. • The formation of Mn vanadate nanosheets can be controlled by growth conditions. • Mn vanadate nanosheets exhibit good photocatalytic activities for methyl blue. - Abstract: Mn vanadate nanosheets have been synthesized via a facile hydrothermal route using ammonium metavanadate and Mn acetate as the raw materials, polyvinyl pyrrolidone (PVP) as the surfactant. X-ray diffraction (XRD) shows that the Mn vanadate nanosheets are composed of monoclinic MnV{sub 2}O{sub 6} phase. Scanning electron microscopy (SEM) observation indicates that the nanosheets have the average thickness of about 50 nm, length of 2–10 μm and width of 800 nm to 2 μm. The growth process of the Mn vanadate nanosheets has also been discussed based on the analysis of the roles of the growth conditions on the formation of the Mn vanadate nanosheets. The nanosheets show good photocatalytic activities for the degradation of methylene blue (MB) under visible light irradiation. About 72.96% MB can be degraded after visible light irradiation for 1 h over 10 mg Mn vanadate nanosheets in 10 mL MB solution with the concentration of 10 mg L{sup −1}.

36 MATERIALS SCIENCE↗

DOE OSTI2014

Synthesis of BiOI flowerlike hierarchical structures toward photocatalytic reduction of CO{sub 2} to CH{sub 4}

BiOI can be used for photocatalytic reduction of CO{sub 2} into hydrocarbon fuels under sunlight. - Highlights: • Room temperature synthesis of BiOI flowerlike hierarchical structures. • BiOI can be used for photocatalytic reduction of CO{sub 2} into hydrocarbon fuels under sunlight. • The photocatalytic activity of BiOI is higher than that of P25 TiO{sub 2}. - Abstract: BiOI flowerlike hierarchical structure was synthesized by the direct hydrolysis method – hydrolysis at room temperature in the presence of polyvinyl pyrrolidone. As-synthesized BiOI was characterized by powder X-ray diffraction, UV–vis diffuse reflectance spectra, X-ray photoelectron spectroscopy spectra, scanning electron microscopy, transmission electron microscopy, and high-resolution transmission electron microscopy. It is a facile way to obtain BiOI flowerlike hierarchical structure photocatalyst for photocatalytic reduction of CO{sub 2} into hydrocarbon fuels under simulated sunlight irradiation without cocatalyst. And the photocatalytic activity of as-synthesized BiOI is higher than that of P25 TiO{sub 2} and bulk BiOI.

36 MATERIALS SCIENCE↗

DOE OSTI2014

Cation distribution in Ni–Cu–Zn nanoferrites from {sup 57}Fe in-field Mössbauer spectra

Highlights: • Occupancy of copper ions at about 20% towards tetrahedral sites. • Distribution is proposed on the basis of % of Fe ions at both A and B sites. • Distribution is checked by estimating the theoretical lattice constant values. - Abstract: The nanoparticles of Ni{sub 1−x}Cu{sub x}Zn{sub 0.35}Fe{sub 2}O{sub 4} were synthesized by sol–gel method using polyvinyl alcohol as a chelating agent. X-ray diffraction patterns of all the samples confirmed the single phase spinel structure. The site occupancy of copper in the nanosized nickel–zinc ferrite spinels was investigated with the help of in-field Mössbauer spectroscopy. Cation distribution for the whole series of compositions was proposed by considering the amounts of iron ions present at both tetrahedral and octahedral interstitial sites in the spinel lattice. Confirmation of the proposed distributions was done by estimating quantitatively the lattice parameters for these compositions and comparing their values with those of the experimentally observed ones.

36 MATERIALS SCIENCE↗

DOE OSTI2016

Low temperature synthesis of nano alpha-alumina powder by two-step hydrolysis

Highlights: • The nano α-Al{sub 2}O{sub 3} with good dispersion was prepared by two-step hydrolysis. • α-Al{sub 2}O{sub 3} powders were added as seed particles in the hydrolysis. • This article indicated that the glucose could impel the γ-Al{sub 2}O{sub 3} transformed to α-Al{sub 2}O{sub 3} directly. • This article indicated that the addictive of α-Al{sub 2}O{sub 3} seed could improve the phase transformation rate of γ-Al{sub 2}O{sub 3} to α-Al{sub 2}O{sub 3}. • In this article, the pure α-Al{sub 2}O{sub 3} could be obtained by calcining at 1000 °C for 1.5 h. - Abstract: The ultral fine alpha-alumina powder has been successfully synthesized via two-step hydrolysis of aluminum isopropoxide. Glucose and polyvinyl pyrrolidone were used as surfactants during the appropriate processing step. The alpha-alumina powder was used as seed particles. Several synthesis parameters, such as the amount of seeds, surfactants, and calcination temperature, were studied by X-ray diffraction (XRD), Fourier transform infrared spectra (FTIR), Thermogravimetry-differential scanning calorimetry (TG-DSC), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The experimental results showed that glucose greatly lower the phase transformation temperature of alpha-alumina by impelling the gamma-alumina transformed to alpha-alumina directly, and the seed could improve the phase transformation rate of alpha-alumina, the polyvinylpyrrolidone have an effect on preventing excessive grain growth and agglomeration of alpha-alumina powder. Comparatively well dispersed alpha-alumina powder with particle size less than 50 nm can be synthesized through this method after calcinations at 1000 °C for 2 h.

36 MATERIALS SCIENCE↗

DOE OSTI2017

Enhanced visible light photocatalytic activity of porous LaMnO{sub 3} sub-micron particles in the degradation of rose bengal

Highlights: • The monodispersed LaMnO{sub 3} microstructure was prepared by hydrothermal method. • The growth of different shaped LaMnO{sub 3} particles was obtained by varying annealing temperatures. • Porous LaMnO{sub 3} microstructure possessed superior photocatalytic activity in rose bengal dye. • The morphology and high surface area influence the enhanced photocatalytic activity. - Abstract: A perovskite LaMnO{sub 3} micro/nanostructure is a promising high-efficiency photocatalytic materials for the removal of various organic pollutants. This study presents the preparation of sub-micron LaMnO{sub 3} particles with polyvinyl pyrrolidone (PVP) as a structure directing agent to control the primary morphology and aggregations. Furthermore, the sample was annealed at different temperatures to improve the crystallinity and perovskite phase formations. The possible formation mechanism was explained based on the annealing temperatures. An attempt has been made to study the effect of different morphologies of LaMnO{sub 3} particles for the degradation of RB dye under visible light irradiation. The removal efficiency of 95% for RB dye in 60 min evidences the superior degradation capability of highly porous LaMnO{sub 3} particles. The photocatalytic activity not only depends on porous structure, but also strongly based on crystallinity, and specific surface area of LaMnO{sub 3} particles. Hence, the porous morphology displays a superior photocatalytic activity than other LaMnO{sub 3} microstructures.

36 MATERIALS SCIENCE↗

DOE OSTI2017

Growth, microstructure, structural and optical properties of PVP-capped CdS nanoflowers for efficient photocatalytic activity of Rhodamine B

Highlights: • Synthesis of un-capped and PVP-capped CdS microstructures by Hydrothermal. • Growth of both the flower and dendrite microstructures controlled by the growth time. • Phase transition of CdS from cubic zinc blend to hexagonal by the growth time. • CdS flowers enhanced the photocatalytic performance of RhB under visible light. • PVP-capped CdS showed the highest degradation of 95% of RhB within 120 min. - Abstract: Size and structure tunability of polyvinyl pyrolidone (PVP) capped cadmium sulfide (PVP-capped CdS) flowers were synthesized by controlling the reaction time. XRD pattern indicated a phase transition from the cubic zinc blend to the hexagonal phase of CdS powder as the reaction time increased. As per the microstructure analysis with respect to the reaction time, the spherical nanoparticles were transformed in to the flower like morphology consisting of sword like nanorods and confirmed by the bright field images of TEM, while, HR-TEM images showed the uniform lattice spacing. UV-spectra exhibited a red shift due to the excitations of CdS nanoparticles. The near band edge (NBE) peak of PVP-capped CdS was completely diminished which indicated to sulphur vacancies on the surface of flowers. The photocatalytic activity of PVP-capped CdS flowers was detected the fast degradation of Rhodamine B (RhB) dye (95% for 120 min) by irradiation of visible light.

36 MATERIALS SCIENCE↗

DOE OSTI2018

Photocatalytic activity of electrospun MgO nanofibres: Synthesis, characterization and applications

Highlights: • MgO nanofibres with high photocatalytic activity were successfully fabricated. • Electrospinning method via PVA/magnesium precursor based system was used. • Dye degradation of MgO nanofibres was compared with spherical MgO nanoparticles. • MgO nanofibres exhibited excellent photocatalytic activity against Reactive Yellow. • MgO nanofibres show a great potential in efficient treatment of dye effluents. - Abstract: One dimensional MgO nanofibres with high photocatalytic activity were fabricated using the electrospinning method via a polyvinyl alcohol (PVA)/magnesium precursor based system and the dye degradation efficacy of MgO nanofibres was compared with MgO nanospheres. Optimum electrospinning parameters including suitable magnesium precursors were investigated and the formation of MgO nanofibres were confirmed with scanning electron microscopy (SEM) and energy dispersive x-ray (EDX) mapping. Furthermore, the crystalline lattice structure and surface roughness of fabricated nanofibres were evaluated using transmission electron microscopic-electron diffraction mode (TEM-SAED) and atomic force microscopy (AFM), respectively. Fabricated MgO nanofibres exhibited excellent photocatalytic degradation activity against widely used model reactive dye, Reactive Yellow (RY). In contrast to MgO nanospheres, electrospun MgO nanofibres completely degraded the reactive dye under UV irradiation. These photocatalytic MgO nanofibres show a great potential to be used in efficient treatment of industrial dye effluents.

77 NANOSCIENCE AND NANOTECHNOLOGY↗

DOE OSTI2018

The investigation of NaTi2(PO4)3@C/Ag as a high-performance anode material for aqueous rechargeable sodium-ion batteries

Highlights: • Facile preparation of NaTi{sub 2}(PO{sub 4}){sub 3}@C/Ag. • An extraordinary self-rejuvenation process was observed every other 20–30 cycles. • Retain a capacity of 71.7 mA h g{sup −1} even at 5 C after 200 cycles. - Abstract: Silver and carbon coated NaTi{sub 2}(PO{sub 4}){sub 3} is synthesized via a facile sol-gel method, with polyvinyl alcohol as carbon source and silver nitrate as Ag source. NaTi{sub 2}(PO{sub 4}){sub 3}@C/Ag is characterized by XRD, SEM, TEM, EDS and XPS. It can be found that C/Ag composite layer is uniformly coated on the surface of NaTi{sub 2}(PO{sub 4}){sub 3}. Compared with the pure NaTi{sub 2}(PO{sub 4}){sub 3}, NaTi{sub 2}(PO{sub 4}){sub 3}@C/Ag material demonstrates significantly higher rate capability and cycling stability. It can deliver an initial discharge capacity of 126.5 mA h g{sup −1} at a current rate of 2 C with the capacity retention of 94.5% after 100 cycles. It can still deliver an initial discharge capacity of 97.5 mA h g{sup −1} at a current rate of 5 C with a substantial capacity retention of 83.8% after 400 cycles. It is worth mentioning that NaTi{sub 2}(PO{sub 4}){sub 3}@C/Ag also exhibits pretty good rate capacity. When the current density ranges from 1 C, 2 C, 5 C, 10 C and finally back to 1 C, NaTi{sub 2}(PO{sub 4}){sub 3}@C/Ag electrode still retains a discharge capacity of 84.6 mAh g{sup −1} after 200 cycles at 5 C corresponding to a capacity retention ratio of 83.5%.

36 MATERIALS SCIENCE↗

DOE OSTI2018

Structural and optical analysis of Fe doped NiO nanoparticles synthesized by chemical precipitation route

Highlights: • The Fe doped NiO nanoparticles were synthesized by chemical precipitation route. • XRD analysis reveals cubic rock-salt fcc structure of the synthesized nanoparticles. • The Ni-O and Fe-O bonding were confirmed through FTIR spectroscopy. • Existence of nickel or interstitial oxygen vacancies indicates p-type nature of nanoparticles. - Abstract: The Ni{sub 1-x}Fe{sub x}O (x = 0.00, 0.02, 0.04 and 0.06) nanoparticles are synthesized by chemical precipitation route using polyvinyl-pyrrolidone (PVP) and nitrate metal salts. The results of thermogravimetric analysis (TGA) of the synthesized dried hydroxide powders showed that thermal decomposition occurs up to 500 °C so as to form pure Ni{sub 1-x}Fe{sub x}O. Therefore, all synthesized samples were calcined at 500 °C for 4 h and then used for further characterization. Energy dispersive X-ray spectroscopy (EDS) of all the samples showed the presence of Ni, O and Fe without any other impurities. From X-ray diffraction (XRD) and transmission electron microscopy (TEM) we could prove that the samples are polycrystalline in nature and are in single phase. The different vibrational modes in Ni{sub 1-x}Fe{sub x}O (x = 0.00, 0.02, 0.04 and 0.06) nanoparticles were studied by Raman spectroscopy and Fourier transform infrared spectroscopy (FTIR). Further, we analyzed the optical response from ultraviolet-visible spectra and Photoluminescence (PL) spectra.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

DOE OSTI2016

Neutron spectroscopy by thermalization light yield measurement in a composite heterogeneous scintillator

An exothermic neutron capture reaction can be used to uniquely identify neutrons in particle detectors. With the use of a capture-gated coincidence technique, the sequence of scatter events that lead to neutron thermalization prior to the neutron capture can also be used to measure neutron energy. We report on the measurement of thermalization light yield via a time-of-flight technique in a polyvinyl toluene-based scintillator EJ-290 within a heterogeneous composite detector that also includes 6Li-doped glass scintillator. The thermalization light output exhibits a strong correlation with neutron energy because of the preference for near-complete energy deposition prior to the 6Li(n,t)4He neutron capture reaction. The nonproportionality of the light yield from nuclear recoils contributes to the observed broadening of the distribution of thermalization light output. The nonproportional dependence of the scintillation light output in the EJ-290 scintillator as a function of proton recoil energy has been characterized in the range of 0.3–14.1 MeV via the Birks parametrization through a combination of time-of-flight measurement and previously conducted measurements with Monoenergetic neutron sources.

6Li-doped scintillator↗

DOE OSTI2018

Tensile, flexural, and light output measurements of selected organic scintillators for evaluation of their potential as structural materials

In order to design structures, such as unmanned vehicle structures, out of plastic scintillator, e.g., for radionuclide searches, suitable materials must either be identified or developed. In searches utilizing unmanned vehicles, the absence of an additional detector attached to the vehicle body as a payload could enable the vehicle to travel faster, carry a longer lived battery, or carry other auxiliary equipment which may be useful for search and/or response. To this end, four mechanical characteristics of selected organic scintillators manufactured by Eljen technologies, Sandia Livermore, and Lawrence Livermore National Lab have been measured. Specifically, tensile and flexural tests have been performed to ASTM specifications on organic scintillators with polyvinyl toluene (PVT), polystyrene (PS), or crosslinked versions of these bases. In addition to these mechanical tests, light output testing was performed in order to quantify whether crosslinking or adding organometallic complexes affects light output in the particular scintillator compositions we measured. We found that the tested plastic scintillators have strengths that are comparable to common structural plastics. We also show that chemically modifying the polymer base can show improvements in the mechanical properties without being overly detrimental to the scintillator light output.

42 ENGINEERING↗

DOE OSTI2020

Compound pulse characteristics of a heterogeneous composite scintillator in a gamma-ray field

An important aspect of radiation detection in scintillators is the time dependence of emitted fluorescence, which results in characteristic measured pulse shape. In some materials, a relatively strong dependence of the scintillation pulse shape on stopping power exists, which can provide reliable identification of the incident particle. An alternative method to realize particle identification is by combining materials with different fluorescence lifetimes into heterogeneous structures. Such composite scintillators derive their properties from both the constituent material characteristics and the geometry of the composite structure. In composite scintillators with a high degree of heterogeneous loading, a superposition of fluorescence contributions originating in multiple materials, which is observed as single waveform with an intermediate pulse shape, may affect its ability to reject rays. We measure the time dependence of light output from a scintillator composed of 6 Li-containing glass shards and scintillating polyvinyl toluene and identify events that exhibit such compound behavior when exposed to rays and fast neutrons. We develop a modeling and simulation framework that reproduces the pulse shapes in heterogeneous scintillators and use it study the effect that the weight percentage of 6 Li glass has on rejection. The modeling framework is applied to the experimentally studied scintillator, finding a good agreement. Here, the developed modeling and simulation approach will help optimize the design of heterogeneous scintillators to meet the desired trade-o between neutron capture efficiency and -ray rejection.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

DOE OSTI2022

Quantifying spatial resolution in a fast neutron radiography system

Neutron imaging is a powerful nondestructive examination modality that has been employed in various applications. Fast neutrons provide advantages over lower energy neutrons, such as examining thicker samples and inducing negligible activation and transmutations. However, fast neutrons interact mostly via elastic scattering with both the neutron detector and the object, causing degradation in spatial resolution. This study explores the quantification of spatial resolution caused by the testing target itself and suggests proper candidate materials for characterizing spatial resolution in terms of modulation transfer function. Knife-edge radiographs of 3 mm, 6 mm, and 5 cm thick Tantalum (Ta) foils, and a 2.54 cm Tungsten (W) cube were acquired using a CCD-based imaging system and a Polyvinyl Toluene (PVT) scintillator at the Ohio State Research Reactor (OSURR)’s fast neutron beam facility. The spatial resolutions calculated were 195 ± 20 μm, 224 ± 22 μm, 248 ± 25 μm, and 435 ± 44 μm for 3 mm, 6 mm, and 5 cm Ta foils, and 2.54 cm W cube, respectively. The results showed a worsening spatial resolution with increasing target thickness. Simulations and calculations estimate that elastic scattering kinematics between neutrons and protons in the PVT medium also limits spatial resolution, and it sets a lower limit of ~44 μm on the spatial resolution for 2 MeV neutrons.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗