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At least 343 records · Page 19
All sourcesNASA NTRSDOE OSTI
DOE OSTI2011

Aqueous-based route toward Fe:ZnSe semiconductor nanocrystals: Synthesis and characterization

Nearly monodisperse and luminescent Fe-doped ZnSe semiconductor nanocrystals were synthesized by an aqueous-based route. The obtained nanocrystals were characterized by X-ray diffraction, transmission electron microscopy, Fourier transform infrared spectroscopy, energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, photoluminescence and ultraviolet-visible absorption spectroscopy. The resulting nanocrystals were well retained in the zinc blende structure, and the Fe dopants were doped into the ZnSe nanocrystals, as confirmed by X-ray photoelectron spectroscopy. From combination of transmission electron microscopy result and computing methods according to ultraviolet-visible absorption spectrum and X-ray diffraction pattern, particle size of the obtained nanocrystals was found to be about 5 nm. Thioglycolic acid as ligand was successfully capped on the surface of the resulting nanocrystals, confirmed by Fourier transform infrared and energy dispersive X-ray spectroscopy. The obtained nanocrystals exhibit an emission peak at 431 nm; and the photoluminescence band is relatively narrow and symmetric, which indicates that the nanocrystals are nearly monodisperse and homogeneous. Absorption shoulder of the resulting nanocrystals is blue-shifted compared with that of corresponding bulk ZnSe, indicating the quantum confinement effect. The possible reaction mechanism of formation of Fe-doped ZnSe nanocrystals in the aqueous solution was also discussed. Our results demonstrate that the aqueous-based route could be successfully adopted for producing high-quality doped semiconductor nanocrystals. - Research Highlights: {yields} An aqueous-based route is demonstrated for synthesizing Fe:ZnSe nanocrystals. {yields} Structure, composition and optical properties of the nanocrystals were investigated. {yields} The synthetic route could be adopted for producing high-quality doped nanocrystals.

36 MATERIALS SCIENCE↗
DOE OSTI2011

Synthesis and characterization of porous ZnO nanoparticles by hydrothermal treatment of as pure aqueous precursor

Graphical abstract: ZnO nanocrystals are predominately prepared by soft chemical methods such as sol-gel and hydrothermal. Although hydrothermal approach is very simple, complexing agents or mineralizers such as alkali metal hydroxide are generally used. There is always a high probability that these cations will be incorporated within the nanocrystals. Such unintentional doping is detrimental to the intrinsic property of the material and will impede its effective application. Here we report a very simple and effective hydrothermal approach to synthesize ZnO nanocrystal without employing any mineralizers. Research highlights: The manuscript reports synthesis of ZnO nanoparticle by simple thermal treatment of aqueous precursor without using any assisting mineralizing agent. The highlights of the findings are as follows: {yields} Aqueous synthesis of ZnO nanoparticles is demonstrated without using any mineralizer. {yields} The method minimizes the risk of unintentional doping due to mineralizers. {yields} The synthesized ZnO nanoparticles had a non-uniform mesoporous structure. {yields} The porous ZnO nanoparticls exhibited size dependent optical absorption. -- Abstract: The presence of the complexing agents in the growth solution poses risk of the unintentional doping in the synthesized product and hence is likely to adversely affect the intrinsic properties. Herein we report the synthesis of ZnO nanoparticles with porous microstructure using pure aqueous precursor. Crystalline ZnO nanoparticles were synthesized by thermal treatment of aqueous solution of zinc acetate in an open bath. The size of the nanocrystals was controlled by changing the initial precursor concentration. The structural and optical properties of the synthesized nanocrystals were analyzed by X-ray diffraction, high resolution transmission electron microscopy, UV-vis absorption and room temperature photoluminescence measurement techniques. The TEM and UV-vis spectral signature analyses confirmed the formation of dispersed single crystalline ZnO nanoparticles. The nanopowders were found to have disordered mesoporous structure. The synthesized nanocrystals exhibited characteristic band edge emission as well as to surface defect related deep level visible luminescence.

36 MATERIALS SCIENCE↗
DOE OSTI2019

NASICON-type Na 3 Fe 2 (PO 4 ) 3 as a low-cost and high-rate anode material for aqueous sodium-ion batteries

Aqueous sodium-ion batteries are attractive battery alternatives for stationary energy storage due to their inherently low cost and high safety. The development of advanced electrode materials with excellent performance and low cost is crucial for the success of aqueous Na-ion batteries. Albeit the high capacity and stable cycling of the leading anode of NaTi 2 (PO 4 ) 3 , the high price of titanium element and the low Na-insertion potential close to the hydrogen evolution reaction may plague its application. Here we introduced a NASICON-type Na 3 Fe 2 (PO 4 ) 3 as a promising anode alternative for aqueous Na-ion batteries. Synchrotron X-ray diffraction and spectroscopy confirm its phase and atomic structure. Electrochemical characterization and X-ray photoelectron spectroscopy reveal the reversible Na+ insertion in Na 3 Fe 2 (PO 4 ) 3 due to the Fe 3+ /Fe 2+ redox couple, which renders a specific capacity of ~60 mAh g -1 and excellent cycling of 1000 cycles at 10C rate. A Super high rate of 100C was also achieved for this anode with a capacity retention of 61% after 1000 cycles. In addition, the Na 3 Fe 2 (PO 4 ) 3 anode is paired with a Prussian white analogue of Na 2 Mn[Fe(CN) 6 ] into a full cell, exhibiting promising cell performance and material sustainability. Furthermore, our work underlines the importance of fabricating aqueous batteries on the basis of the Earth-abundant, cost-effective, and non-toxic elements.

25 ENERGY STORAGE↗
DOE OSTI2017

Reforming Biomass Derived Pyrolysis Bio-oil Aqueous Phase to Fuels

Fast pyrolysis and catalytic fast pyrolysis (CFP) of biomass produce a liquid product stream comprised of various classes of organic compounds having different molecule size and polarity. This liquid, either spontaneously in the case of catalytic fast pyrolysis or by water addition for the non-catalytic process separates into a non-polar organic-rich fraction and a highly polar water-rich fraction. The organic fraction can be used as a blendstock or feedstock for further processing in a refinery while, in the CFP process design, the aqueous phase is currently sent to wastewater treatment, which results in a loss of residual biogenic carbon present in this stream. Our work focuses on the catalytic conversion of the biogenic carbon in pyrolysis aqueous phase streams to produce hydrocarbons using a vertical micro-reactor coupled to a molecular beam mass spectrometer (MBMS). Furthermore, the MBMS provides real-time analysis of products while also tracking catalyst deactivation. The catalyst used in this work was HZSM-5, which upgraded the oxygenated organics in the aqueous fraction to fuels comprising small olefins and aromatic hydrocarbons. During processing the aqueous bio-oil fraction the HZSM-5 catalyst exhibited higher activity and coke resistance than those observed in similar experiments using biomass or whole bio-oils. Reduced coking is likely due to ejection of coke precursors from the catalyst pores that was enhanced by excess process water available for steam stripping. The water reacted with coke precursors to form phenol, methylated phenols, naphthol, and methylated naphthols. Conversion data shows that up to 40 wt% of the carbon in the feed stream is recovered as hydrocarbons.

09 BIOMASS FUELS↗
DOE OSTI2020

Effects of Extended Aqueous Processing on Structure, Chemistry, and Performance of Polycrystalline LiNi x Mn y Co z O 2 Cathode Powders

The prospect of aqueous processing of LiNi x Mn y Co z O 2 (NMC) cathodes has significant appeal to battery manufacturers for the reduction in materials cost, toxicological risk, and environmental impact compared to conventional N -methyl-2-pyrrolidone (NMP)-based processing. However, the effects of aqueous processing of NMC powders at industrial timescales are not well studied, with prior studies mostly focusing on relatively brief water washing processes. Here, we investigate the bulk and surface impacts of extended aqueous processing of polycrystalline NMC powders with different compositions. We demonstrate that at timescales of several hours, polycrystalline NMC is susceptible to intergranular fracture, with the severity of fracture scaling with the NMC nickel content. While bulk crystallinity and composition are unchanged, surface sensitive techniques such as X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) indicate that the exposure of water leads to a level of delithiation, nickel reduction, and reconstruction from the layered to rock-salt structure at the surface of individual grains. Dynamic single NMC microparticle compression testing suggests that the resulting mechanical stresses weaken the integrity of the polycrystalline particle and increases susceptibility of intergranular fracture. The initially degraded surfaces along with the increased surface area lead to faster capacity fade and impedance growth during electrochemical cycling. From this work, it is demonstrated that NMC powders require surface or grain boundary modifications to make industrial-scale aqueous cathode processing viable, especially for next-generation nickel-rich NMC chemistries.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2016

Ethylene glycol reforming on Pt(111): first-principles microkinetic modeling in vapor and aqueous phases

First-principles, periodic density functional theory (DFT) calculations and mean-field microkinetic modeling have been used to investigate the decomposition of ethylene glycol for hydrogen production on Pt(111) in vapor and aqueous phases. All dehydrogenated species derived from ethylene glycol (C 2 H x O 2 , x = 0–6) and methanol (CH y O, y = 0–4), and all elementary C–C, C–H, and O–H bond breaking steps are included in the microkinetic model. Reaction path analysis in vapor phase indicates that both initial C–H and O–H dehydrogenation steps are kinetically relevant at all temperatures (470–530 K). Initial O–H bond cleavage is reversible at low temperatures but accounts for an increasingly dominant fraction of the total reaction flux at higher temperatures. C–C bond scission is observed only after significant dehydrogenation (x ≤ 3) and is more likely to happen in surface intermediates where one of the cleavage products is CO. Here, the process is highly selective to the production of H2 compared to methanol. For aqueous-phase model development, free energies of solvation were computed for all surface intermediates and transition states using a continuum solvation approach. Our aqueous-phase microkinetic model predicts a 0.4 eV lower apparent activation energy and an order of magnitude larger turnover frequencies. Initial C–H bond cleavage becomes more important but the general trends are similar to the vapor phase, suggesting that the reaction chemistry is similar in both vapor and aqueous phases.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2016

Ultrafast excited-state deactivation of 9-methylhypoxanthine in aqueous solution: A QM/MM MD study

Photoinduced ultrafast non-adiabatic decay of 9-methylhypoxanthine (9MHPX) in aqueous solution was investigated by ab initio surface-hopping dynamics calculations using a combined quantum mechanical/molecular mechanical approach. The absorption spectra of 9MHPX in aqueous solution were also explored by the hybrid cluster-continuum model at the level of time-dependent density functional theory along with the polarizable continuum model (PCM). The static electronic-structure calculations indicate that the absorption spectra of 9MHPX simulated by TD-B3LYP/PCM and TD-X3LYP/PCM can reproduce very well the experimental findings, with the accuracy of about 0.20 eV. According to dynamics simulations, irradiation of 9MHPX populates the bright excited singlet S{sub 1} state, which may undergo an ultrafast non-radiative deactivation to the S{sub 0} state. The lifetime of the S{sub 1} state of 9MHPX in aqueous solution is predicted to be 115.6 fs, slightly longer than that in the gas phase (88.8 fs), suggesting that the solvent water has no significant influence on the excited-state lifetime of 9MHPX. Such a behavior in 9MHPX is distinctly different from its parent hypoxanthine keto-N9H tautomer in which the excited-state lifetime of the latter in water solution was remarkably enhanced as compared to the gas phase. The significant difference of the photodynamical behaviors between 9MHPX and keto-N9H can be ascribed to their different hydrogen bond environment in aqueous solution.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2015

Aqueous Geochemistry at High Pressures and High Temperatures

This project is aimed at experimental characterization of the sound velocities, equations of state (EOS), and derived physical and chemical properties of aqueous solutions and carbon dioxide at extreme pressure and temperature conditions relevant to processes occurring in the interior of the Earth. Chemical transport, phase changes (including melting), fluid-solid reactions, and formation of magmatic liquids at convergent plat boundaries are a key motivation for this project. Research in this area has long been limited by the extreme experimental challenges and lack of data under the appropriate pressure-temperature (P-T) conditions. The vast majority of studies of aqueous geochemistry relevant to terrestrial problems of fluid-rock interactions have been conducted at 0.3 GPa or less, and the widely used Helgeson-Kirkham-Flowers equation of state for aqueous species is applicable only at ~ < 0.5 GPa. These limits are unfortunate because fluid flow and reactions plays a central role in many deeper environments. Recent efforts including our own, have resulted in new experimental techniques that now make it possible to investigate properties of homogeneous and heterogeneous equilibria involving aqueous species and minerals over a much broader range of pressure and temperature appropriate for deep crustal and upper mantle processes involving water-rich fluids. We carried out 1) Brillouin scattering measurements of the equations of state and molar volume of water and carbon dioxide to over 10 GPa and 870K using precise resistance heating of samples under pressure in the diamond anvil cell, and 2) the phase diagrams of the water and CO2, and 3) Exploring new experimental approaches, including CO2 laser heating of samples in a diamond cell, to measurements of sound velocities, EOS, and phase relations by Brillouin scattering to far greater pressures and temperatures.

58 GEOSCIENCES↗
DOE OSTI2023

Cost-Benefit Assessment of Krypton and Xenon Recovery from Aqueous Reprocessing

The purpose of this paper is to provide an understanding of the cost-benefit of capturing Kr and Xe from the existing process of aqueous reprocessing of UNF. The study accomplishes this with a market assessment of Xe prices and volumes today, coupled with a cost estimate of Kr and Xe capture out of cryogenic distillation within aqueous reprocessing. The market assessment shows that the average price of Xe is about $\$ $60/L while the average price of Kr is about $\$ $1/L. The assessment also shows that the market structure for Xe is one of oligopoly, in other words, very few suppliers to the Xe market. The assessment shows growing demand for Xe, particularly in medical applications like anesthesia. The cost assessment finds the unit cost of Xe to range from $\$ $71.50/L to $\$ $131.13/L. This range is only slightly above the current range of market prices today, and with growing demand for Xe, prices could reach the range it would take to support extraction of Xe from aqueous reprocessing. On the other hand, the estimated cost range for Kr is $\$ $830.15/L up to $\$ $1,522.52/L, which far exceeds the range of market prices for Kr. However, as the text notes, Kr capture is already part of aqueous reprocessing so these costs are sunk costs (already incurred) whereas the cost estimates for Xe are marginal cost (if Xe is desired, then the cost estimate would result from the Xe capture).

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2023

Progresses and Perspectives of All‐Iron Aqueous Redox Flow Batteries

Abstract Redox flow batteries (RFBs) are a promising option for long‐duration energy storage (LDES) due to their stability, scalability, and potential reversibility. However, solid‐state and non‐aqueous flow batteries have low safety and low conductivity, while aqueous systems using vanadium and zinc are expensive and have low power and energy densities, limiting their industrial application. An approach to lower capital cost and improve scalability is to utilize cheap Earth‐abundant metals such as iron (Fe). Nevertheless, all‐iron RFBs have many complications, involving voltage loss from ohmic resistance, side reactions such as hydrogen evolution, oxidation, and most significantly electrode plating, and dendrite growth. To address these issues, researchers have begun to examine the effects of various alterations to all‐iron RFBs, such as adding organic ligands to form Fe complexes and using a slurry electrode instead of common materials such as graphite or platinum rods. Overall, progress in improving aqueous all‐iron RFBs is at its infant stage, and new strategies must be introduced, such as the utilization of nanoparticles, which can limit dendrite growth while increasing storage capacity. This review provides an in‐depth overview of current research and offers perspectives on how to design the next generation of all‐iron aqueous RFBs.

Belongia, Shawn↗
DOE OSTI2020

A Non‐aqueous H 3 PO 4 Electrolyte Enables Stable Cycling of Proton Electrodes

Abstract A non‐aqueous proton electrolyte is devised by dissolving H 3 PO 4 into acetonitrile. The electrolyte exhibits unique vibrational signatures from stimulated Raman spectroscopy. Such an electrolyte exhibits unique characteristics compared to aqueous acidic electrolytes: 1) higher (de)protonation potential for a lower desolvation energy of protons, 2) better cycling stability by dissolution suppression, and 3) higher Coulombic efficiency owing to the lack of oxygen evolution reaction. Two non‐aqueous proton full cells exhibit better cycling stability, higher Coulombic efficiency, and less self‐discharge compared to the aqueous counterpart.

Xu, Yunkai↗
DOE OSTI2014

Excellent stability of a lithium-ion-conducting solid electrolyte upon reversible Li + /H + exchange in aqueous solutions

Batteries with an aqueous catholyte and a Li metal anode have attracted interest owing to their exceptional energy density and high charge/discharge rate. The long-term operation of such batteries requires that the solid electrolyte separator between the anode and aqueous solutions must be compatible with Li and stable over a wide pH range. Unfortunately, no such compound has yet been reported. In this study, an excellent stability in neutral and strongly basic solutions was observed when using the cubic Li 7 La 3 Zr 2 O 12 garnet as a Li-stable solid electrolyte. The material underwent a Li + /H + exchange in aqueous solutions. Nevertheless, its structure remained unchanged even under a high exchange rate of 63.6%. When treated with a 2 M LiOH solution, the Li + /H + exchange was reversed without any structural change. Furthermore, these observations suggest that cubic Li 7 La 3 Zr 2 O 12 is a promising candidate for the separator in aqueous lithium batteries.

25 ENERGY STORAGE↗
DOE OSTI2014

Reentrant condensation of lysozyme: Implications for studying dynamics of lysozyme in aqueous solutions of lithium chloride

Recent studies have outlined the use of eutectic solution of lithium chloride in water to study microscopic dynamics of lysozyme in an aqueous solvent that is remarkably similar to pure water in many respects, yet allows experiments over a wide temperature range without the solvent crystallization. The eutectic point in (H2O)R(LiCl) system corresponds to R 7.3, and it is of interest to investigate whether less concentrated aqueous solutions of LiCl could be employed in low-temperature studies of a solvated protein. We have investigated a range of concentrations of lysozyme and LiCl in aqueous solutions to identify systems that do not show phase separation and avoid solvent crystallization on cooling down. Compared to the lysozyme concentration in solution, the concentration of LiCl in the aqueous solvent plays the major role in determining systems suitable for low-temperature studies. We have observed interesting and rich phase behavior reminiscent of reentrant condensation of proteins.

Mamontov, Eugene↗
DOE OSTI2023

On Energy Storage Chemistry of Aqueous Zn-Ion Batteries: From Cathode to Anode

Rechargeable aqueous zinc-ion batteries (ZIBs) have resurged in large-scale energy storage applications due to their intrinsic safety, affordability, competitive electrochemical performance, and environmental friendliness. Extensive efforts have been devoted to exploring high-performance cathodes and stable anodes. However, many fundamental issues still hinder the development of aqueous ZIBs. Here, we critically review and assess the energy storage chemistries of aqueous ZIBs for both cathodes and anodes. First, this review presents a comprehensive understanding of the cathode charge storage chemistry, probes the existing deficiencies in mechanism verification, and analyzes contradictions between the experimental results and proposed mechanisms. Then, a detailed summary of the representative cathode materials and corresponding comparative discussion is provided with typical cases encompassing structural features, electrochemical properties, existing drawbacks, and feasible remedies. Subsequently, the fundamental chemical properties, remaining challenges, and improvement strategies of both Zn metal and non-Zn anodes are presented to thoroughly explore the energy storage chemistry of ZIBs and pursue the development of high-performance ZIBs. Furthermore, the progress of mechanistic characterization techniques and theoretical simulation methods used for ZIBs is timely reviewed. Finally, here we provide our perspectives, critical analysis, and insights on the remaining challenges and future directions for development of aqueous ZIBs.

25 ENERGY STORAGE↗
DOE OSTI2025

Quantification of the REE 3+ aqua ions and chloride species in aqueous fluids by in situ Raman spectroscopy using perturbations of the water band

Acidic NaCl-rich aqueous fluids play a crucial role in forming hydrothermal rare earth elements (REE) mineral deposits. Aqueous REE mobility is mostly controlled by the stabilities of REE 3+ and REE chloride species. Our current knowledge of REE speciation is based on solubility data, thermodynamic models and in situ spectroscopic measurements, sometimes coupled with molecular simulations. Here, in this study, we investigate Nd and Yb speciation in pH2 Cl-bearing solutions at 25 °C and 0.1 MPa with variable Cl/REE ratios using Raman Spectroscopy in solutions with 0.1 to 0.6 mol/kg NdCl 3 or YbCl 3 and 0.2 to 3.2 mol/kg NaCl. Due to the challenges in resolving the REE-Cl band, we developed a new method using the water vibrational mode and multivariate curve resolution (MCR) analysis. The Raman spectra for the vibrational band of water (2700 to 3900 cm –1 ) were collected at 25 °C and fitted by three Gaussian sub-peaks, then quantified using MCR analysis to de-convolute the water band into bulk H 2 O and the perturbations caused by of Cl – , REE 3+ , and REE chloride species. REE speciation based on the perturbations of the water band indicates that REE 3+ aqua ions dominate acidic solutions at 25 °C, but up to ~20 mol% YbCl 2+ forms at high YbCl 3 concentrations. The new method is promising for quantifying in situ speciation of the REE 3+ aqua ions and REE chloride species in aqueous fluids while providing information on the hydration of ions. This method improves our molecular level understanding of REE aqueous species stability and their role in REE mobilization during fluid-rock interaction.

58 GEOSCIENCES↗
DOE OSTI2011

Dissolved carbonic anhydrase for enhancing post-combustion carbon dioxide hydration in aqueous ammonia

Aqueous ammonia solvents that capture CO2 as ionic complexes of carbonates with ammonium have recently been advanced as alternatives to amine-based solvents due to their lower energy requirements for thermal regeneration. In ammonia based solvents, the hydration of CO2 to form bicarbonate may become a rate-limiting step as the CO2 loading increases and the resulting pH level of the solvent decreases. Variants of the enzyme carbonic anhydrase can accelerate the reversible hydration of CO2 to yield bicarbonate by more than 10(6)-fold. The possible benefit of bovine carbonic anhydrase (BCA) addition to solutions of aqueous ammonia to enhance CO2 hydration was investigated in semi-batch reactions within continuously stirred tank reactors or in a bubble column gas-liquid contactor. Adding 154 mg/liter of BCA to 2 M aqueous ammonia provided a 34.1% overall increase in the rate of CO2 hydration (as indicated by the production of [H+]) as the pH declined from 9.6 to 8.6 during sparging with a 15% CO2, 85% N-2 gas at a flow rate of 3 lpm. The benefits of adding BCA to enhance CO2 hydration were only discernable below similar to pH 9. The implications of the apparent pH limitations on the utility of BCA are discussed in the context of absorber unit operation design. Possible embodiments of carbonic anhydrase as either an immobilized catalyst or as a dissolved, recirculating catalyst in potential plant scale aqueous ammonia systems are considered as well. (C) 2010 Published by Elsevier Ltd.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2014

Natural Oil-Based Emulsion Containing Allantoin Versus Aqueous Cream for Managing Radiation-Induced Skin Reactions in Patients With Cancer: A Phase 3, Double-Blind, Randomized, Controlled Trial

Purpose: To investigate the effects of a natural oil-based emulsion containing allantoin versus aqueous cream for preventing and managing radiation-induced skin reactions. Methods and Materials: A total of 174 patients were randomized and participated in the study. Patients received either cream 1 (the natural oil-based emulsion containing allantoin) or cream 2 (aqueous cream). Skin toxicity, pain, itching, and skin-related quality of life scores were collected for up to 4 weeks after radiation treatment. Results: Patients who received cream 1 had a significantly lower average level of Common Terminology Criteria for Adverse Events at week 3 (P<.05) but had statistically higher average levels of skin toxicity at weeks 7, 8, and 9 (all P<.001). Similar results were observed when skin toxicity was analyzed by grades. With regards to pain, patients in the cream 2 group had a significantly higher average level of worst pain (P<.05) and itching (P=.046) compared with the cream 1 group at week 3; however, these differences were not observed at other weeks. In addition, there was a strong trend for cream 2 to reduce the incidence of grade 2 or more skin toxicity in comparison with cream 1 (P=.056). Overall, more participants in the cream 1 group were required to use another topical treatment at weeks 8 (P=.049) and 9 (P=.01). Conclusion: The natural oil-based emulsion containing allantoin seems to have similar effects for managing skin toxicity compared with aqueous cream up to week 5; however, it becomes significantly less effective at later weeks into the radiation treatment and beyond treatment completion (week 6 and beyond). There were no major differences in pain, itching, and skin-related quality of life. In light of these results, clinicians and patients can base their decision on costs and preferences. Overall, aqueous cream seems to be a more preferred option.

62 RADIOLOGY AND NUCLEAR MEDICINE↗