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We present the first report of the concentrations and stable isotope compositions of Te in the surface layer of ferromanganese crusts collected from the slope of two seamounts in the Northwest Pacific Ocean, Takuyo-Daigo and Takuyo-Daisan, which cover water depths from 1000 to 5500 m. The Te concentration in the surface layer of the ferromanganese crusts sharply decreases with increasing depth at shallow regions, but this decrease becomes more gradual at deeper regions. The Te isotope composition exhibits two trends that become (1) lighter with increasing water depth at shallow depths and (2) heavier with increasing water depth at greater depths. These profiles are the same for the two seamounts and indicate two types of correlations between the concentration and isotope composition with water depth. The turning points are located at approximately 2000 m for Takuyo-Daigo and 3200 m for Takuyo-Daisan, which likely correspond to different oxygen minimum zones. Co-precipitation processes with Fe and oxidation involving Mn may be responsible for the variation of Te concentration and isotope composition with water depth. These processes are also related to a change of the dissolved oxygen concentration in ambient seawater. The Te isotope compositions in ferromanganese crusts may therefore serve as a potential proxy for changes of the oxygen minimum zone of paleoceans. [ABSTRACT FROM AUTHOR]

Isoscalar monopole and dipole transitions are investigated in the medium and heavier systems, such as 44 Ti and even 104 - 110 Te nuclei by employing the macroscopic α cluster model of α + 40 Ca and α + 100 - 106 Sn , respectively. Theoretical calculations predict that the strengths of the monopole and dipole transitions are strongly enhanced in the excitation energy below 10 MeV. These low-lying enhancements are induced by the excitation in the relative motion of the α cluster and the residual nucleus, and the magnitudes of the transition matrix element are comparable to the single nucleon excitation, which requires much higher excitation energy than the energy for the α excitation. The electric dipole strength is also calcluated for 135 Cs with the cluster model of α + 131 I , which is a kind of nuclear waste. The application of the monopole and dipole transitions involving the α emission to the nuclear transmutation of the nuclear wastes is also discussed. [ABSTRACT FROM AUTHOR]

The ground state nuclear structure properties of the proton rich even-even tellurium isotopes are studied by using Gogny energy density functional within the framework of Hartree-Fock-Bogoliubov (HFB) method. The HFB equations are solved by using the axial cylindrical transformed deformed harmonic oscillator basis. The full parameterization of Gogny energy density functional is employed in the present study. The evolution of the neutron density distributions with an increase in neutron number is studied and emergence of various nuclear structure phenomena is investigated. Besides this, the ground state nuclear structure properties such as nuclear multipole moments, deformation parameters, binding energies, pairing energies, root mean square radii and charge radii are obtained for the even-even proton-rich tellurium isotopes. The theoretical results on the nuclear ground state properties are compared with the available experimental data and good agreement is found. [ABSTRACT FROM AUTHOR]

Abstract The selenium stable isotope system emerges as a new potential tracer of volatile origin and evolution of the terrestrial planets. Accurate determination of the mantle Se isotope composition requires an assessment of Se isotopic behavior in magmatic processes and potential variations across all mantle reservoirs. Here we report the first high-precision Se isotope and Se–Te abundance data for a suite of basaltic glasses from the Pacific–Antarctic ridge. These MORBs display a narrow range in δ82/76Se values (deviation of 82Se/76Se relative to NIST SRM 3149) between −0.30 ± 0.09‰ and −0.05 ± 0.09‰, with an average of −0.16 ± 0.13‰ (2 s.d., n = 27). We quantify the main processes relevant to MORB petrogenesis in order to better understand the Se–Te elemental behavior in the mantle and investigate if these are systematically related to Se isotope variations. We show that both Se isotopes and S–Se–Te abundances of MORB melts remain unaffected by assimilation of high-temperature hydrothermal fluids and sulfides, whereas the latter has been shown to overprint the 34S/32S ratios. MORB differentiation involving sulfide segregation (sulfide liquid and monosulfide solid solution) significantly fractionates Se and Te (Se/Te ratio ∼ 45–190), with no systematic Se isotope variation. The Se–Te contents of the primary MORB melt corrected for magmatic differentiation can be successfully reproduced by near-fractional decompression melting of a mantle with 170–200 μg g−1 S (as sulfide liquid), which has either (1) "fertile lherzolite-like" Se and Te contents (80 ± 17 and 11 ± 1.7 ng g−1, respectively; 1 s.d.) or (2) distinctly lower Se (49 ± 11 ng g−1) and Te (3.5 ± 1.3 ng g−1) contents depending on the choice of experimental partition coefficients published by different studies. Regardless, our model shows that Se-Te systematics of "fertile" lithospheric peridotites preserve little primary melt depletion signatures and reflect significant, if not complete, metasomatic overprinting. Finally, based on the observed negligible Se isotopic fractionation between sulfide phase and silicate melt, we suggest that MORBs preserve their mantle source isotopic signature (δ82/76Se = −0.16 ± 0.13‰). Our MORB average is similar within uncertainty to chondritic values but significantly lighter than previously published δ82/76Se data for basalts from a variety of geodynamic settings. The subtle but significant Se isotope variation observed within the investigated MORB suite (up to ∼0.25‰) and between other mantle samples analyzed so far may reflect intrinsic source heterogeneity and potential isotopic differences across various mantle reservoirs. [ABSTRACT FROM AUTHOR]

Abstract: As a rare element with special properties, tellurium (Te) is an important resource that has been widely used in many fields. In this paper, a novel renewable cotton fabric based Zn-Al layered double hydroxide (LDH) functionalized carbon aerogel (ZALCA) was successfully prepared by a facile freeze-drying, carbonization and in situ growth method, which can be used for tellurium adsorption. The scanning electron microscopy results showed that the flowerlike LDH nano-sheets are growing evenly on the surface of carbon aerogel and each LDH nano-sheet has a similar shape and size. The nitrogen sorption analysis confirmed that mesoporous ZALCA has the pores centered at about 3-5 nm and Brunauer-Emmett-Teller surface area of 186.38 m2/g. Adsorption experiment results show that the ZALCA has excellent adsorption properties for tellurium ions in tellurium-containing solutions, and the maximum adsorption capacity is 132 mg/g. After recycling 10 times, the ZALCA still displayed high tellurium absorption property implies that the ZALCA has outstanding reusability performance. Therefore, the preparation of ZALCA as a tellurium adsorbent from low-cost cotton has great application potential in the recovery of tellurium.Graphical abstract: [ABSTRACT FROM AUTHOR]

Abstract: Nonlayered materials are constructed with chemical covalent bonds in all three dimensions, distinct from layered materials, which contain evident structural differences in the horizontal and vertical directions. As a consequence, liquid‐phase exfoliation (LPE), a widely explored technique to obtain 2D layered nanoarchitectures, has not yet been fully characterized for the realization of 2D nonlayered nanostructures. Herein, by virtue of a typical chain‐like structure of crystalline bulk Te with strong TeTe covalent bonds in intrachains and weak Van der Waals forces in interchains, ultrathin 2D nonlayered Te nanosheets are realized by means of an LPE method. The resultant 2D Te nanosheets possess a broad lateral dimension ranging from 41.5 to 177.5 nm and a thickness ranging from 5.1 to 6.4 nm, and its photoresponse properties are evaluated using photoelectrochemical measurements. The 2D Te nanosheets exhibit excellent photoresponse behaviors from the UV to the visible regime in association with strong time and cycle stability for the on/off switching behaviors. The fabrication approach of 2D Te nanosheets would arouse interest in exfoliating other nonlayered 2D materials, which would expand the family of 2D materials. [ABSTRACT FROM AUTHOR]

Samples of red bed sediments in several Mesoproterozoic successions contain enrichments of tellurium (Te), including discrete telluride minerals. The tellurides were neoformed during redox-controlled diagenesis, rather than representing mechanical concentrations of heavy minerals. Tellurium is enriched relative to selenium, which may reflect erosion of Archean and Palaeoproterozoic rocks with high Te contents. High continentality during the Mesoproterozoic would have limited the delivery of Te and other trace elements to the oceans, so accumulated Te on the continents. [ABSTRACT FROM AUTHOR]

New methodologies employing a 125 Te- 128 Te double-spike were developed and applied to obtain high precision mass-dependent tellurium stable isotope data for chondritic meteorites and some terrestrial samples by multiple-collector inductively coupled plasma mass spectrometry. Analyses of standard solutions produce Te stable isotope data with a long-term reproducibility (2SD) of 0.064‰ for δ 130/125 Te. Carbonaceous and enstatite chondrites display a range in δ 130/125 Te of 0.9‰ (0.2‰ amu −1 ) in their Te stable isotope signature, whereas ordinary chondrites present larger Te stable isotope fractionation, in particular for unequilibrated ordinary chondrites, with an overall variation of 6.3‰ for δ 130/125 Te (1.3‰ amu −1 ). Tellurium stable isotope variations in ordinary chondrites display no correlation with Te contents or metamorphic grade. The large Te stable isotope fractionation in ordinary chondrites is likely caused by evaporation and condensation processes during metamorphism in the meteorite parent bodies, as has been suggested for other moderately and highly volatile elements displaying similar isotope fractionation. Alternatively, they might represent a nebular signature or could have been produced during chondrule formation. Enstatite chondrites display slightly more negative δ 130/125 Te compared to carbonaceous chondrites and equilibrated ordinary chondrites. Small differences in the Te stable isotope composition are also present within carbonaceous chondrites and increase in the order CV-CO-CM−CI. These Te isotope variations within carbonaceous chondrites may be due to mixing of components that have distinct Te isotope signatures reflecting Te stable isotope fractionation in the early solar system or on the parent bodies and potentially small so-far unresolvable nucleosynthetic isotope anomalies of up to 0.27‰. The Te stable isotope data of carbonaceous and enstatite chondrites displays a general correlation with the oxidation state and hence might provide a record of the nebular formation environment. The Te stable isotope fractionation of the carbonaceous chondrites CI and CM (and CO potentially) overlap within uncertainty with data for terrestrial Te standard solutions, sediments and ore samples. Assuming the silicate Earth displays similar Te isotope fractionation as the studied terrestrial samples, the data indicate that the late veneer might have been delivered by material similar to CI or CM (or possibly) CO carbonaceous chondrites in terms of Te isotope composition. Nine terrestrial samples display resolvable Te stable isotope fractionation of 0.85 and 0.60‰ for δ 130/125 Te for sediment and USGS geochemical exploration reference samples, respectively. Tellurium isotopes therefore have the potential to become a new geochemical sedimentary proxy, as well as a proxy for ore-exploration. [ABSTRACT FROM AUTHOR]

The distribution and chemical species of tellurium (Te) in contaminated soil were determined by a combination of microfocused X-ray fluorescence (?-XRF), X-ray diffraction (?-XRD), and X-ray absorption fine structure (?-XAFS) techniques. Results showed that Te was present as a mixture of Te(VI) and Te(IV) species, while selenium (Se) was predominantly present in the form of Se(IV) in the soil contaminated by abandoned mine tailings. In the contaminated soil, Fe(III) hydroxides were the host phases for Se(IV), Te(IV), and Te(VI), but Te(IV) could be also retained by illite. The difference in speciation and solubility of Se and Te in soil can result from different structures of surface complexes for Se and Te onto Fe(III) hydroxides. Furthermore, our results suggest that the retention of Te(IV) in soil could be relatively weaker than that of Te(VI) due to structural incorporation of Te(VI) into Fe(III) hydroxides. These findings are of geochemical and environmental significance for better understanding the solubility, mobility, and bioavailability of Te in the surface environment. To the best of our knowledge, this is the first study reporting the speciation and host phases of Te in field soil by the ?-XRF-XRD-XAFS techniques. [ABSTRACT FROM AUTHOR]

We present the performances of two 92% enriched 130 TeO 2 crystals operated as thermal bolometers in view of a next generation experiment to search for neutrinoless double beta decay of 130 Te. The crystals, 435 g each, show an energy resolution, evaluated at the 2615 keV γ -line of 208 Tl, of 6.5 and 4.3 keV FWHM. The only observable internal radioactive contamination arises from 238 U (15 and 8 μBq/kg, respectively). The internal activity of the most problematic nuclei for neutrinoless double beta decay, 226 Ra and 228 Th, are both evaluated as <3.1 μBq/kg for one crystal and <2.3 μBq/kg for the second. Thanks to the readout of the weak Cherenkov light emitted by β / γ particles by means of Neganov–Luke bolometric light detectors we were able to perform an event-by-event identification of β / γ events with a 95% acceptance level, while establishing a rejection factor of 98.21% and 99.99% for α particles. [ABSTRACT FROM AUTHOR]

The tellurium isotope compositions of naturally-occurring tellurides, native tellurium, and tellurites were measured by multicollector-inductively coupled plasma-mass spectrometry (MC-ICP-MS) and compared to theoretical values for equilibrium mass-dependent isotopic fractionation of representative Te-bearing species estimated with first-principles thermodynamic calculations. Calculated fractionation models suggest that 130/125 Te fractionations as large as 4‰ occur at 100 °C between coexisting tellurates (Te VI) and tellurides (Te −II) or or native tellurium Te(0), and smaller, typically <1‰, fractionations occur between coexisting Te(−I) or Te(−II) (Au,Ag)Te 2 minerals (i.e., calaverite, krennerite) and (Au,Ag) 2 Te minerals (i.e., petzite, hessite). In general, heavy Te/ light Te is predicted to be higher for more oxidized species, and lower for reduced species. Tellurides in the system Au–Ag–Te and native tellurium analyzed in this study have values of δ 130/125 Te = −1.54‰ to 0.44‰ and δ 130/125 Te = −0.74‰ to 0.16‰, respectively, whereas those for tellurites (tellurite, paratellurite, emmonsite and poughite) range from δ 130/125 Te = −1.58‰ to 0.59‰. Thus, the isotopic composition for both oxidized and reduced species are broadly coincident. Calculations of per mil isotopic variation per amu for each sample suggest that mass-dependent processes are responsible for fractionation. In one sample of coexisting primary native tellurium and secondary emmonsite, δ 130/125 Te compositions were identical. The coincidence of δ 130/125 Te between all oxidized and reduced species in this study and the apparent lack of isotopic fractionation between native tellurium and emmonsite in one sample suggest that oxidation processes cause little to no fractionation. Because Te is predominantly transported as an oxidized aqueous phase or as a reduced vapor phase under hydrothermal conditions, either a reduction of oxidized Te in hydrothermal liquids or deposition of Te from a reduced vapor to a solid is necessary to form the common tellurides and native tellurium in ore-forming systems. Our data suggest that these sorts of reactions during mineralization may account for a ∼3‰ range of δ 130/125 Te values. Based on the data ranges for Te minerals from various ore deposits, the underpinning geologic processes responsible for mineralization seem to have primary control on the magnitude of fractionation, with tellurides in epithermal gold deposits showing a narrower range of isotope values than those in orogenic gold and volcanogenic massive sulfide deposits. [ABSTRACT FROM AUTHOR]

We report the enhanced thermoelectric properties in Cu x Bi 0.38 Sb 1.62 Te 3 compounds through simultaneous achievement of improved charge transport and suppressed thermal transport by Cu incorporation. Incorporated Cu acted as an acceptor rather than donor, resulting in the significant improvement of p -type electric conduction. Density of state effective mass was almost linearly proportional to the Cu content in the compounds, and it led to the enhancement of power factor in Cu-doped compounds regardless of the increase in hole concentration. Furthermore, reduction of bipolar and lattice thermal conductivities could also be achieved by the Cu incorporation, consequently leading to the improved thermoelectric properties of the compounds at relatively high temperatures. Effects of Cu on the thermal and charge transport properties are discussed in detail, and the controllability of the thermoelectric performance for optimum operating temperature is also reported. [ABSTRACT FROM AUTHOR]

The electric reduced transition probabilities B(E2)↓ of even-neutron-rich 120-126Te nuclei by means of interacting boson model-1 (IBM-1) are calculated. The R4/2 values of the first 4+ and 2+ levels are also calculated and the U(5) symmetry for these nuclei is indicated. The transition rate R = B(E2: L+→(L-2)+)/ B(E2: 2+→ 0+) of a few lowlying quadrupole collective states is studied systematically and compared with the experimental data. The electric reduced transition probabilities of even 120-126Te nuclei of gamma transition states of 8+→6+, 6+→4+, 4+→2+ and 2+→0+ are studied and compared with the experimental values. In addition, the systematic B(E2) values, intrinsic quadrupole moments and deformation parameters of even neutrons of N= 68-74 in Te isotopes are also studied. All the computed values from the present study are in good agreement with the experimental data. The IBM-1 formula for the reduced transition probabilities B(E2) is analytically deduced in U(5) limit for a few ground-state transitions in even 120-126Te isotopes. [ABSTRACT FROM AUTHOR]

123 I is widely used for radiodiagnostic procedures. It is produced by reaction of 124 Xe (p,2n) 123 Cs → 123 Xe → 123 I in cyclotrons. 121 Te and 125 I appear in a photon energy spectrum as impurities. An activity of 121 Te was calibrated absolutely by sum-peak method and its photon emitting probability was estimated, whose results were consistent with published results. [ABSTRACT FROM AUTHOR]

In this paper, we have considered the vibration to gamma unstable phase transition in the 118–128 Te isotopes. A transitional interacting boson model Hamiltonian in both IBM-1 and IBM-2 versions which are based on affine SU ( 1 , 1 ) ˆ Lie Algebra are employed to describe the evolution from spherical to deformed gamma unstable shapes along the chain of Te isotopes. The excitation energies, B ( E 0 ) and B ( E 2 ) transition rates are rather well reproduced in comparison with experimental counterparts when the weight of SO(6) limit is increased in Hamiltonian. [ABSTRACT FROM AUTHOR]

We report on the first β-decay data of 138Sb to 138Te isotopes beyond the doubly magic 132Sn. The parent nucleus was produced by the in-flight fission of a 238U beam on a 9Be target at 345 MeV per nucleon and measured at the BigRIPS separator of the Radioactive Isotope Beam Factory at RIKEN. By using advanced β-γ spectroscopy techniques, the half-life and the tentative spin-parity of 138Sb were measured to be 346(19) ms and (3-), respectively. In addition, we observed several low-lying non-yrast states in 138Te for the first time. Our data allowed us to rearrange the positions of the first 2+ and 4+ states in this nucleus and to construct the level scheme of 138Te in accordance with shell-model calculations. Additionally, we extend energy systematics of Te isotopes within neutron numbers 54 and 86. [ABSTRACT FROM AUTHOR]

In the present work recently available experimental data for high-spin states of four nuclei, Te 52 124 , Te 52 125 , Te 52 126 , and Te 52 127 , have been interpreted using state-of-the-art shell model calculations. The calculations have been performed in the 50–82 valence shell composed of 1 g 7 / 2 , 2 d 5 / 2 , 1 h 11 / 2 , 3 s 1 / 2 , and 2 d 3 / 2 orbitals. We have compared our results with the available experimental data for excitation energies and transition probabilities, including high-spin states. The results are in reasonable agreement with the available experimental data. The wave functions, particularly, the specific proton and neutron configurations which are involved to generate the angular momentum along the yrast lines are discussed. We have also estimated overall contribution of three-body forces in the energy level shifting. Finally, results with modified effective interaction are also reported. [ABSTRACT FROM AUTHOR]

Flux-averaged cross sections for cosmogenic-neutron activation of natural tellurium were measured using a neutron beam containing neutrons of kinetic energies up to ~800 MeV and having an energy spectrum similar to that of cosmic-ray neutrons at sea level. Analysis of the radioisotopes produced reveals that 110mAg will be a dominant contributor to the cosmogenic-activation background in experiments searching for neutrinoless double-β decay of 130Te, such as the Cryogenic Underground Observatory for Rare Events (CUORE) and the Sudbury Neutrino Observatory Plus (SNO+). An estimate of the cosmogenic-activation background in the CUORE experiment has been obtained using the results of this measurement and cross-section measurements of proton activation of tellurium. Additionally, the measured cross sections in this work are also compared with results from semiempirical cross-section calculations. [ABSTRACT FROM AUTHOR]

The lifetime of the 2+ → 0g.s.+ transition in the neutron-deficicient nucleus 112Te has been measured for the first time using the DPUNS plunger and the recoil distance Doppler shift technique. The deduced value for the reduced transition probability is B(E2:0g.s.+ → 2+) = 0.46 ±0.04 e²b², indicating that there is no unexpected enhancement of the B(E20g.s.+ → 2+) values in Te isotopes below the midshell. The result is compared to and discussed in the framework of large-scale shell-model calculations. [ABSTRACT FROM AUTHOR]

Background: The nucleosynthesis of the neutron-deficient p nuclei remains an open question in nuclear astrophysics. Beside uncertainties on the astrophysical side, the nuclear-physics input parameters entering Hauser-Feshbach calculations for the nucleosynthesis of the p nuclei must be put on a firm basis. Purpose: An extended database of experimental data is needed to address uncertainties of the nuclear-physics input parameters for Hauser-Feshbach calculations. Especially α+nucleus optical model potentials at low energies are not well known. The in-beam technique with an array of high-purity germanium (HPGe) detectors was successfully applied to the measurement of absolute cross sections of an (α,γ) reaction on a heavy nucleus at sub-Coulomb energies. Method: The total and partial cross-section values were measured by means of in-beam γ-ray spectroscopy. For this purpose, the absolute reaction yield was measured using the HPGe detector array HORUS at the FN tandem accelerator at the University of Cologne. Total and partial cross sections were measured at four different a-particle energies from Eα=10.5MeV to Eα=12MeV. Results: The measured total cross-section values are in excellent agreement with previous results obtained with the activation technique, which proves the validity of the applied method. With the present measurement, the discrepancy between two older data sets is removed. The experimental data was compared to Hauser-Feshbach calculations using the nuclear reaction code talys. With a modification of the semi-microscopic α+nucleus optical model potential OMP 3, the measured cross-section values are reproduced well. Moreover, partial cross sections could be measured for the first time for an (α,γ) reaction. Conclusions: A modified version of the semimicroscopic α+nucleus optical model potential OMP3, as well as modified proton and γ widths, are needed in order to obtain a good agreement between experimental data and theory. It is found that a model using a local modification of the nuclear-physics input parameters simultaneously reproduces total cross sections of the 112Sn(α,γ) and 112Sn(α,p) reactions. The measurement of partial cross sections turns out to be very important in this case in order to apply the correct γ-ray strength function in the Hauser-Feshbach calculations. The model also reproduces cross-section values of α-induced reactions on 106Cd, as well as of (α,n) reactions on 115,116Sn, hinting at a more global character of the obtained nuclear-physics input. [ABSTRACT FROM AUTHOR]

130Te is one of the candidates for the search for neutrinoless double beta decay. It is currently planned to be used in two experiments: CUORE and SNO+. In the CUORE experiment TeO2 crystals cooled at cryogenic temperatures will be used. In the SNO+ experiment natTe will be deployed up to 0.3% loading in the liquid scintillator volume. A possible background for the signal searched for, are the high Q-value, long-lived isotopes, produced by cosmogenic neutron and proton spallation reaction on the target material. A total of 18 isotopes with Q-value larger than 2 MeV and T1/2 > 20 days have been identified as potential backgrounds. In addition low Q-value, high rate isotopes can be problematic due to pile-up effects, specially in liquid scintillator based detectors. Production rates have been calculated using the ACTIVIA program, the TENDL library, and the cosmogenic neutron and proton flux parametrization at sea level from Armstrong and Gehrels for both long and short lived isotopes. The obtained values for the cross sections are compared with the existing experimental data and calculations. Good agreement has been generally found. The results have been applied to the SNO+ experiment for one year of exposure at sea level. Two possible cases have been considered: a two years of cooling down period deep underground, or a first purification on surface and 6 months of cooling down deep underground. Deep underground activation at the SNOLAB location has been considered. [ABSTRACT FROM AUTHOR]

Quantum dots (QDs) are generally toxic as a result of their heavy metal content. However, direct characterization of their dissolution behavior in living systems remains complicated because of the lack of differentiation methods suitable for analyzing the released components and residual nanostructures. To investigate the degree of dissolution of QDs in living rats, we used a chemical vapor generation scheme as a novel strategy to selectively vaporize the chalcogen (Te) species released from CdSeTe–ZnS core–shell QDs (QD705) in organ/tissue samples from rats. Under optimized conditions, we established a chemical differentiation method that had a better performance and applicability than the commonly used filtration method. We used Solvable tissue solubilizer to dissolve the tissues harvested from rats that had been administered with QD705 intravenously. Our experimental results showed differences in the Te- and Cd-based biodistribution patterns of QD705. In addition, we found that the ratio of the concentrations of the Te species released from the dissolution of QD705 to the total Te species (Ter/Tetotal) increased in the blood, liver, and spleen of the rats, but decreased in their kidneys from 2 to 16 weeks post-administration. Therefore the QD705 administered in living rats must have dissolved and redistributed progressively during the time course of the experiment, suggesting that the long-term chemical fate of nanosized materials in vivo should be considered in future nanotoxicological research. [ABSTRACT FROM AUTHOR]