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DOE OSTI2022

Precise $\textit{Q}$-value measurements of 112,113 Ag and 115 Cd with the Canadian Penning trap for evaluation of potential ultralow $\textit{Q}$-value $\textit{β}$ decays

Background: An ultralow $\textit{Q}$-value $\textit{β}$ decay can occur from a parent nuclide to an excited nuclear state in the daughter such that $Q_{\text{UL}}$ 1 keV. These decay processes are of interest for nuclear $\textit{β}$-decay theory and as potential candidates in neutrino mass determination experiments. To date, only one ultralow $\textit{Q}$-value $\textit{β}$ decay has been observed—that of 115 In with $Q_β$ = 147(10) eV. A number of other potential candidates exist, but improved mass measurements are necessary to determine if these decay channels are energetically allowed and, in fact, ultralow. Purpose: To perform precise $\textit{β}$-decay $\textit{Q}$-value measurements of 112,113 Ag and 115 Cd and to use them in combination with nuclear energy level data for the daughter isotopes 112,113 Cd and 115 In to determine if the potential ultralow $\textit{Q}$-value $\textit{β}$-decay branches of 112,113 Ag and 115 Cd are energetically allowed and 1 keV. Method: The Canadian Penning Trap at Argonne National Laboratory was used to measure the cyclotron frequency ratios of singly charged 112,113 Ag and 115 Cd ions with respect to their daughters 112,113 Cd and 115 In. From these measurements, the ground-state to ground-state $\textit{β}$-decay $\textit{Q}$ values were obtained. Results: The 112 Ag → 112 Cd, 113 Ag → 113 Cd, and 115 Cd → 115 In $\textit{β}$-decay $\textit{Q}$ values were measured to be $Q_β$( 112 Ag) = 3990.16(22) keV, $Q_β$( 113 Ag) = 2085.7(4.6) keV, and $Q_β$( 115 Cd) = 1451.36(34) keV. These results were compared to energies of excited states in 112 Cd at 3997.75(14) keV, 113 Cd at 2015.6(2.5) and 2080(10) keV, and 115 In at 1448.787(9) keV, resulting in precise $Q_{\text{UL}}$ values for the potential decay channels of –7.59(26) keV, 6(11) keV, and 2.57(34) keV, respectively. Conclusion: The potential ultralow $\textit{Q}$-value decays of 112 Ag and 115 Cd have been ruled out. 113 Ag is still a possible candidate until a more precise measurement of the 2080(10) keV, 1/2+ state of 113 Cd is available. In the course of this work we have found the ground state mass of 113 Ag reported in the 2020 Atomic Mass Evaluation [Wang et al., Chin. Phys. C 45, 030003 (2021)] to be lower than our measurement by 69(17) keV (a 4σ discrepancy).

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

DOE OSTI2020

Materials Data on Cd(GaO2)2 by Materials Project

CdGa2O4 is Spinel-like structured and crystallizes in the trigonal P3m1 space group. The structure is three-dimensional. there are twelve inequivalent Cd2+ sites. In the first Cd2+ site, Cd2+ is bonded to four O2- atoms to form CdO4 tetrahedra that share corners with three equivalent CdO6 octahedra and corners with nine GaO6 octahedra. The corner-sharing octahedra tilt angles range from 57–67°. There are three shorter (2.13 Å) and one longer (2.22 Å) Cd–O bond lengths. In the second Cd2+ site, Cd2+ is bonded to six O2- atoms to form CdO6 octahedra that share corners with three equivalent CdO4 tetrahedra, corners with three equivalent GaO4 tetrahedra, and edges with six GaO6 octahedra. There are three shorter (2.24 Å) and three longer (2.32 Å) Cd–O bond lengths. In the third Cd2+ site, Cd2+ is bonded to four O2- atoms to form CdO4 tetrahedra that share corners with three equivalent CdO6 octahedra and corners with nine GaO6 octahedra. The corner-sharing octahedra tilt angles range from 56–69°. There are three shorter (2.14 Å) and one longer (2.16 Å) Cd–O bond lengths. In the fourth Cd2+ site, Cd2+ is bonded to six O2- atoms to form CdO6 octahedra that share corners with three equivalent CdO4 tetrahedra, corners with three equivalent GaO4 tetrahedra, and edges with six GaO6 octahedra. There are three shorter (2.26 Å) and three longer (2.31 Å) Cd–O bond lengths. In the fifth Cd2+ site, Cd2+ is bonded to four O2- atoms to form CdO4 tetrahedra that share corners with twelve GaO6 octahedra. The corner-sharing octahedra tilt angles range from 59–62°. There are one shorter (2.13 Å) and three longer (2.16 Å) Cd–O bond lengths. In the sixth Cd2+ site, Cd2+ is bonded to four O2- atoms to form CdO4 tetrahedra that share corners with twelve GaO6 octahedra. The corner-sharing octahedral tilt angles are 61°. There are three shorter (2.17 Å) and one longer (2.18 Å) Cd–O bond lengths. In the seventh Cd2+ site, Cd2+ is bonded to four O2- atoms to form CdO4 tetrahedra that share corners with twelve GaO6 octahedra. The corner-sharing octahedra tilt angles range from 60–64°. There are three shorter (2.18 Å) and one longer (2.22 Å) Cd–O bond lengths. In the eighth Cd2+ site, Cd2+ is bonded to four O2- atoms to form CdO4 tetrahedra that share corners with twelve GaO6 octahedra. The corner-sharing octahedra tilt angles range from 61–62°. There are one shorter (2.15 Å) and three longer (2.17 Å) Cd–O bond lengths. In the ninth Cd2+ site, Cd2+ is bonded to four O2- atoms to form CdO4 tetrahedra that share corners with twelve GaO6 octahedra. The corner-sharing octahedra tilt angles range from 61–62°. There are one shorter (2.16 Å) and three longer (2.17 Å) Cd–O bond lengths. In the tenth Cd2+ site, Cd2+ is bonded to four O2- atoms to form CdO4 tetrahedra that share corners with twelve GaO6 octahedra. The corner-sharing octahedral tilt angles are 61°. There are three shorter (2.17 Å) and one longer (2.18 Å) Cd–O bond lengths. In the eleventh Cd2+ site, Cd2+ is bonded to four O2- atoms to form CdO4 tetrahedra that share corners with twelve GaO6 octahedra. The corner-sharing octahedra tilt angles range from 60–61°. There are three shorter (2.16 Å) and one longer (2.18 Å) Cd–O bond lengths. In the twelfth Cd2+ site, Cd2+ is bonded to four O2- atoms to form CdO4 tetrahedra that share corners with twelve GaO6 octahedra. The corner-sharing octahedra tilt angles range from 60–65°. There are three shorter (2.17 Å) and one longer (2.24 Å) Cd–O bond lengths. There are twelve inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share corners with three equivalent CdO6 octahedra and corners with nine GaO6 octahedra. The corner-sharing octahedra tilt angles range from 53–63°. There is three shorter (1.93 Å) and one longer (1.98 Å) Ga–O bond length. In the second Ga3+ site, Ga3+ is bonded to six O2- atoms to form GaO6 octahedra that share corners with three CdO4 tetrahedra, corners with three GaO4 tetrahedra, edges with two CdO6 octahedra, and edges with four equivalent GaO6 octahedra. There are a spread of Ga–O bond distances ranging from 1.96–2.22 Å. In the third Ga3+ site, Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share corners with three equivalent CdO6 octahedra and corners with nine GaO6 octahedra. The corner-sharing octahedra tilt angles range from 52–63°. There is one shorter (1.93 Å) and three longer (1.97 Å) Ga–O bond length. In the fourth Ga3+ site, Ga3+ is bonded to six O2- atoms to form GaO6 octahedra that share a cornercorner with one GaO4 tetrahedra, corners with five CdO4 tetrahedra, an edgeedge with one CdO6 octahedra, and edges with five GaO6 octahedra. There are a spread of Ga–O bond distances ranging from 1.96–2.30 Å. In the fifth Ga3+ site, Ga3+ is bonded to six O2- atoms to form GaO6 octahedra that share corners with six CdO4 tetrahedra and edges with six GaO6 octahedra. There are two shorter (2.03 Å) and four longer (2.05 Å) Ga–O bond lengths. In the sixth Ga3+ site, Ga3+ is bonded to six O2- atoms to form GaO6 octahedra that share corners with six CdO4 tetrahedra and edges with six GaO6 octahedra. There are three shorter (2.02 Å) and three longer (2.04 Å) Ga–O bond lengths. In the seventh Ga3+ site, Ga3+ is bonded to six O2- atoms to form GaO6 octahedra that share corners with six CdO4 tetrahedra and edges with six GaO6 octahedra. There are a spread of Ga–O bond distances ranging from 2.03–2.05 Å. In the eighth Ga3+ site, Ga3+ is bonded to six O2- atoms to form GaO6 octahedra that share corners with six CdO4 tetrahedra and edges with six GaO6 octahedra. There are three shorter (2.03 Å) and three longer (2.05 Å) Ga–O bond lengths. In the ninth Ga3+ site, Ga3+ is bonded to six O2- atoms to form GaO6 octahedra that share corners with six CdO4 tetrahedra and edges with six GaO6 octahedra. There are a spread of Ga–O bond distances ranging from 2.03–2.05 Å. In the tenth Ga3+ site, Ga3+ is bonded to six O2- atoms to form GaO6 octahedra that share corners with six CdO4 tetrahedra and edges with six GaO6 octahedra. There are three shorter (2.03 Å) and three longer (2.05 Å) Ga–O bond lengths. In the eleventh Ga3+ site, Ga3+ is bonded to six O2- atoms to form GaO6 octahedra that share corners with two equivalent GaO4 tetrahedra, corners with four CdO4 tetrahedra, an edgeedge with one CdO6 octahedra, and edges with five GaO6 octahedra. There are four shorter (2.02 Å) and two longer (2.12 Å) Ga–O bond lengths. In the twelfth Ga3+ site, Ga3+ is bonded to six O2- atoms to form GaO6 octahedra that share corners with six CdO4 tetrahedra and edges with six GaO6 octahedra. There are three shorter (2.02 Å) and three longer (2.03 Å) Ga–O bond lengths. There are twenty-four inequivalent O2- sites. In the first O2- site, O2- is bonded to two Cd2+ and two equivalent Ga3+ atoms to form a mixture of distorted edge and corner-sharing OCd2Ga2 trigonal pyramids. In the second O2- site, O2- is bonded to one Cd2+ and three equivalent Ga3+ atoms to form a mixture of distorted edge and corner-sharing OCdGa3 trigonal pyramids. In the third O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Cd2+ and three Ga3+ atoms. In the fourth O2- site, O2- is bonded to two Cd2+ and two equivalent Ga3+ atoms to form distorted OCd2Ga2 trigonal pyramids that share corners with four equivalent OCdGa3 tetrahedra, corners with three OCdGa3 trigonal pyramids, and edges with three OCd2Ga2 trigonal pyramids. In the fifth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to four Ga3+ atoms. In the sixth O2- site, O2- is bonded to one Cd2+ and three equivalent Ga3+ atoms to form distorted OCdGa3 trigonal pyramids that share corners with nine OCdGa3 tetrahedra and edges with three equivalent OCd2Ga2 trigonal pyramids. In the seventh O2- site, O2- is bonded to one Cd2+ and three Ga3+ atoms to form OCdGa3 tetrahedra that share corners with six OCdGa3 tetrahedra, corners with six OCd2Ga2 trigonal pyramids, and edges with two equivalent OCdGa3 tetrahedra. In the eighth O2- site, O2- is bonded to one Cd2+ and three Ga3+ atoms to form a mixture of distorted edge and corner-sharing OCdGa3 tetrahedra. In the ninth O2- site, O2- is bonded in a rectangular see-saw-like geometry to four Ga3+ atoms. In the tenth O2- site, O2- is bonded to one Cd2+ and three equivalent Ga3+ atoms to form a mixture of distorted edge and corner-sharing OCdGa3 tetrahedra. In the eleventh O2- site, O2- is bonded to one Cd2+ and three Ga3+ atoms to form a mixture of distorted edge and corner-sharing OCdGa3 tetrahedra. In the twelfth O2- site, O2- is bonded to one Cd2+ and three Ga3+ atoms to form a mixture of distorted edge and corner-sharing OCdGa3 tetrahedra. In the thirteenth O2- site, O2- is bonded to one Cd2+ and three equivalent Ga3+ atoms to form a mixture of distorted edge and corner-sharing OCdGa3 tetrahedra. In the fourteenth O2- site, O2- is bonded to one Cd2+ and three equivalent Ga3+ atoms to form a mixture of distorted edge and corner-sharing OCdGa3 tetrahedra. In the fifteenth O2- site, O2- is bonded to one Cd2+ and three Ga3+ atoms to form a mixture of distorted edge and corner-sharing OCdGa3 tetrahedra. In the sixteenth O2- site, O2- is bonded to one Cd2+ and three Ga3+ atoms to form a mixture of distorted edge and corner-sharing OCdGa3 tetrahedra. In the seventeenth O2- site, O2- is bonded to one Cd2+ and three equivalent Ga3+ atoms to form a mixture of distorted edge and corner-sharing OCdGa3 tetrahedra. In the eighteenth O2- site, O2- is bonded to one Cd2+ and three equivalent Ga3+ atoms to form a mixture of distorted edge and corner-sharing OCdGa3 tetrahedra. In the nineteenth O2- site, O2- is bonded to one Cd2+ and three Ga3+ atoms to form a mixture of distorted edge and corner-sharing OCdGa3 tetrahedra. In the twentieth O2- site, O2- is bonded to one Cd2+ and three Ga3+ atoms to form a mixture of distorted edge and corner-sharing OCdGa3 tetrahedra. In the twenty-first O2- site, O2- is bonded to one Cd2+ and three equivalent Ga3+ atoms to form a mixture of distorted edge and corner-sharing OCdGa3 tetrahedra. In the twenty-second O2- site, O2- is bonded to one Cd2+ and three equivalent Ga3+ atoms to form distorted OCdGa3 trigonal pyramids that share corners with three equivalent OCdGa3 tetrahedra, corners with three equivalent OCd2Ga2 trigonal pyramids, and edges with three equivalent OCdGa3 tetrahedra. In the twenty-third O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Cd2+ and three Ga3+ atoms. In the twenty-fourth O2- site, O2- is bonded to one Cd2+ and three equivalent Ga3+ atoms to form corner-sharing OCdGa3 tetrahedra.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on Cd by Materials Project

Cd is alpha La structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Cd sites. In the first Cd site, Cd is bonded to twelve Cd atoms to form a mixture of edge, corner, and face-sharing CdCd12 cuboctahedra. There are six shorter (3.07 Å) and six longer (3.29 Å) Cd–Cd bond lengths. In the second Cd site, Cd is bonded to twelve Cd atoms to form a mixture of edge, corner, and face-sharing CdCd12 cuboctahedra. All Cd–Cd bond lengths are 3.29 Å.

36 MATERIALS SCIENCE↗

NASA NTRS2001

Dynamics of cD Clusters of Galaxies: Conclusion of a Survey of 25 Abell Clusters - 4

We present the final results of a spectroscopic study of a sample of cD galaxy clusters. The goal of this program has been to study the dynamics of the clusters, with emphasis on determining the nature and frequency of cD galaxies with peculiar velocities. Redshifts measured with the MX Spectrometer have been combined with those obtained from the literature to obtain typically 50 - 150 observed velocities in each of 25 galaxy clusters containing a central cD galaxy. We present a dynamical analysis of the final 11 clusters to be observed in this sample. All 25 clusters are analyzed in a uniform manner to test for the presence of substructure, and to determine peculiar velocities and their statistical significance for the central cD galaxy. These peculiar velocities were used to determine whether or not the central cD galaxy is at rest in the cluster potential well. We find that 30 - 50% of the clusters in our sample possess significant subclustering (depending on the cluster radius used in the analysis), which is in agreement with other studies of non-cD clusters. Hence, the dynamical state of cD clusters is not different than other present-day clusters. After careful study, four of the clusters appear to have a cD galaxy with a significant peculiar velocity. Dressler-Shectman tests indicate that three of these four clusters have statistically significant substructure within 1.5/h(sub 75) Mpc of the cluster center. The dispersion 75 of the cD peculiar velocities is 164 +41/-34 km/s around the mean cluster velocity. This represents a significant detection of peculiar cD velocities, but at a level which is far below the mean velocity dispersion for this sample of clusters. The picture that emerges is one in which cD galaxies are nearly at rest with respect to the cluster potential well, but have small residual velocities due to subcluster mergers.

Oegerle, William R.↗

DOE OSTI2023

Structural Characterization of Toxicologically Relevant Cd 2+ -L-Cysteine Complexes

The exposure of humans to Cd exerts adverse human health effects at low chronic exposure doses, but the underlying biomolecular mechanisms are incompletely understood. To gain insight into the toxicologically relevant chemistry of Cd 2+ in the bloodstream, we employed an anion-exchange HPLC coupled to a flame atomic absorption spectrometer (FAAS) using a mobile phase of 100 mM NaCl with 5 mM Tris-buffer (pH 7.4) to resemble protein-free blood plasma. The injection of Cd 2+ onto this HPLC-FAAS system was associated with the elution of a Cd peak that corresponded to [CdCl 3 ] - /[CdCl 4 ] 2- complexes. The addition of 0.1–10 mM L-cysteine (Cys) to the mobile phase significantly affected the retention behavior of Cd 2+ , which was rationalized by the on-column formation of mixed CdCysxCly complexes. From a toxicological point of view, the results obtained with 0.1 and 0.2 mM Cys were the most relevant because they resembled plasma concentrations. The corresponding Cd-containing (~30 μM) fractions were analyzed by X-ray absorption spectroscopy and revealed an increased sulfur coordination to Cd 2+ when the Cys concentration was increased from 0.1 to 0.2 mM. The putative formation of these toxicologically relevant Cd species in blood plasma was implicated in the Cd uptake into target organs and underscores the notion that a better understanding of the metabolism of Cd in the bloodstream is critical to causally link human exposure with organ-based toxicological effects.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2022

Improvements to the 115g/115m Cd Nuclear Data

Repeated measurements of the isotope 115m Cd by Los Alamos National Laboratory (LANL), Pacific Northwest National Laboratory (PNNL), and Atomic Weapons Establishment (AWE) have revealed a consistent discrepancy between beta and gamma counting. This suggests that a significant disparity exists between the true value of the isotope’s gamma-ray branching ratios and the values reported by the National Nuclear Data Center (NNDC). Enriched 114 Cd was irradiated using thermal neutrons to produce a high-purity 115m/g Cd source for counting and analysis using traditional singles gamma-ray spectroscopy, liquid scintillation counting, gas-proportional counting, and analysis using the new Gamma-Alpha-Beta-Gamma (GABγ) and Gamma-Alpha-Beta Radio-Isotope EvaLuator (GABRIEL) coincidence detection systems. Using the D-T fusion generated neutrons, reduces the wait time required to let the short-lived 115Cd ground state decay away by leveraging the 1:1 production ratio of the ground and metastable state of 115 Cd from the 115 In (n,p) reaction relative to the 10:1 production ratio of the ground and metastable isotopes of 115 Cd by thermal neutron capture on 114 Cd. However, the much higher flux in from the Washington State University TRIGA reactor is a more rapid method of production of 115m/gCd but requires access to enriched 114 Cd. High purity 115m/g Cd samples were analyzed on regular intervals over a period of 140-days. The activity of 115m Cd measured by beta and gamma show a clear discrepancy using the current best known gamma-ray decay branching ratios. Based on these observations and measurements, a set of new branching ratio recommendations have been produced using conventional counting techniques and the advanced GAB? and GABRIEL instruments.

07 ISOTOPE AND RADIATION SOURCES↗

DOE OSTI2021

Development of arsenic doped Cd(Se,Te) absorbers by MOCVD for thin film solar cells

Recent developments in CdTe solar cell technology have included the incorporation of ternary alloy Cd(Se,Te) in the devices. CdTe absorber band gap grading due to Se alloying contributes to current density enhancement and can result in device performance improvement. Here we report Cd(Se,Te) polycrystalline thin films grown by a chamberless inline atmospheric pressure metal organic chemical vapour deposition technique, with subsequent incorporation in CdTe solar cells. The compositional dependence of the crystal structure and optical properties of Cd(Se,Te) are examined. Selenium graded Cd(Se,Te)/CdTe absorber structure in devices are demonstrated using either a single CdSe layer or CdSe/Cd(Se,Te) bilayer (with or without As doping in the Cd(Se,Te) layer). Cross-sectional TEM/EDS, photoluminescence spectra and secondary ion mass spectroscopy analysis confirmed the formation of a graded Se profile toward the back contact with a diffusion length of ~1.5 um and revealed back-diffusion of Group V (As) dopants from the CdTe layer into Cd(Se,Te) grains. Due to the strong Se/Te interdiffusion, CdSe in the Se bilayer configuration was unable to form an n-type emitter layer in processed devices. In situ As doping of the Cd(Se,Te) layer benefited the device junction quality with current density reaching 28.3 mA/cm 2 . The results provide useful insights for the optimisation of Cd(Se,Te)/CdTe solar cells.

14 SOLAR ENERGY↗

DOE OSTI2020

Materials Data on Cd(PO5)2 by Materials Project

Cd(PO5)2 crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of one Cd(PO5)2 sheet oriented in the (-1, 0, 2) direction. Cd is bonded to six O atoms to form CdO6 octahedra that share corners with four equivalent PO4 tetrahedra. There are a spread of Cd–O bond distances ranging from 2.25–2.37 Å. P is bonded to four O atoms to form PO4 tetrahedra that share corners with two equivalent CdO6 octahedra. The corner-sharing octahedra tilt angles range from 34–50°. There are a spread of P–O bond distances ranging from 1.52–1.57 Å. There are five inequivalent O sites. In the first O site, O is bonded in a distorted bent 120 degrees geometry to one Cd and one P atom. In the second O site, O is bonded in a single-bond geometry to one P atom. In the third O site, O is bonded in a single-bond geometry to one P atom. In the fourth O site, O is bonded in a bent 150 degrees geometry to one Cd and one P atom. In the fifth O site, O is bonded in a single-bond geometry to one Cd atom.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on Cd(NO5)2 by Materials Project

Cd(NO3)2(O2)2 crystallizes in the orthorhombic Fdd2 space group. The structure is zero-dimensional and consists of sixteen hydrogen peroxide molecules and eight Cd(NO3)2 clusters. In each Cd(NO3)2 cluster, Cd is bonded in a 4-coordinate geometry to four O atoms. There are two shorter (2.26 Å) and two longer (2.30 Å) Cd–O bond lengths. N is bonded in a trigonal planar geometry to three O atoms. There is one shorter (1.22 Å) and two longer (1.30 Å) N–O bond length. There are three inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one N atom. In the second O site, O is bonded in an L-shaped geometry to one Cd and one N atom. In the third O site, O is bonded in an L-shaped geometry to one Cd and one N atom.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on Cd(AsO4)4 by Materials Project

Cd(AsO4)4 crystallizes in the triclinic P-1 space group. The structure is one-dimensional and consists of one Cd(AsO4)4 ribbon oriented in the (1, 0, 0) direction. Cd is bonded to six O atoms to form CdO6 octahedra that share corners with six AsO4 tetrahedra. There are a spread of Cd–O bond distances ranging from 2.23–2.34 Å. There are two inequivalent As sites. In the first As site, As is bonded to four O atoms to form AsO4 tetrahedra that share a cornercorner with one CdO6 octahedra. The corner-sharing octahedral tilt angles are 53°. There are a spread of As–O bond distances ranging from 1.71–1.76 Å. In the second As site, As is bonded to four O atoms to form AsO4 tetrahedra that share corners with two equivalent CdO6 octahedra. The corner-sharing octahedra tilt angles range from 50–55°. There are a spread of As–O bond distances ranging from 1.71–1.75 Å. There are eight inequivalent O sites. In the first O site, O is bonded in a bent 120 degrees geometry to one Cd and one As atom. In the second O site, O is bonded in a single-bond geometry to one As atom. In the third O site, O is bonded in a single-bond geometry to one As atom. In the fourth O site, O is bonded in a single-bond geometry to one As atom. In the fifth O site, O is bonded in a bent 120 degrees geometry to one Cd and one As atom. In the sixth O site, O is bonded in a single-bond geometry to one As atom. In the seventh O site, O is bonded in a bent 120 degrees geometry to one Cd and one As atom. In the eighth O site, O is bonded in a single-bond geometry to one As atom.

36 MATERIALS SCIENCE↗

DOE OSTI2021

Chemiresistor sensor based on ion-imprinted polymer (IIP)-functionalized rGO for Cd(II) ions in water

This study reports the design and development of a novel chemiresistor (CR) sensor using ion imprinted polymer (IIP)-functionalized reduced graphene oxide (rGO) [IIP/rGO-CR] for cadmium ions (Cd(II)) determination in water. The sensor consisted of a CR transducer made of rGO channel bridging source and drain electrodes prepared by self-assembly and thermal reduction of graphene oxide (GO) on Au interdigitated electrodes chip fabricated on Si/SiO 2 substrate. The IIP was then grafted on rGO using surface-initiated reversible addition-fragmentation chain transfer (RAFT) polymerization with polyethylenimine (PEI) and methylacrylic acid (MAA) as dual functional monomers and Cd(II) ions as template through UV light-initiated copolymerization. The IIP functionalized on rGO acted as an effective recognition element that modulated the resistance of rGO-CR upon binding of Cd(II), enabling Cd(II) detection at ppb level in aqueous solutions. The prepared IIP/rGO-CR sensor worked effectively in the linear range of 2~200ppb and achieved a limit of detection (LOD) of 0.83 ppb, which is lower than the World Health Organization guidelines of 3ppb for drinking water quality. The developed sensor of IIP/rGO-CR showed a high selectivity against a variety of trace and heavy metal ions found in water and good stability for up to 60 days when stored at room temperature for Cd(II) determination in water. Further, the sensor was successfully applied to analyzing Cd(II) spiked in tap, lake and river waters with a 94.5%–113.5% recovery, demonstrating a high degree of accuracy even in complex water samples. Finally, our results illustrated that the CR sensor of IIP functionalized rGO provides a potential platform for sensitive, robust and low-cost environmental analysis of Cd(II) in water.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

NASA NTRS1982

Distribution and evolution of Zn, Cd, and Pb in Apollo 16 regolith samples and the average U-Pb ages of the parent rocks

The concentration of surface (low temperature site) and interior (high temperature site) Cd, Zn, and Pb in 13 Apollo 16 highland fines samples, pristine rock 65325, and mare fines sample 75081 were analyzed directly from the thermal release profiles obtained by flameless atomic absorption technique (FLAA). Cd and Zn in pristine ferroan anothosite 65325, anorthositic grains of the most mature fines 65701, and basaltic rock fragments of mare fines 75081 were almost all surface Cd and Zn indicating that most volatiles were deposited on the surfaces of vugs, vesicles and microcracks during the initial cooling process. A considerable amount of interior Cd and Zn was observed in agglutinates. This result suggests that high temperature site interior volatiles originate from entrapment during the lunar maturation processes. Interior Cd found in the most mature fines sample 65701 was only about 15% of the total Cd in the sample. Interior Pb present in Apollo 16 fines samples went up to 60%. From our Cd studies we can assume that this interior Pb in highland fines samples is largely due to the radiogenic decay which occurred after the redistribution of the volatiles took place. We obtained an average age of 4.0 b.y. for the parent rocks of Apollo 16 highland regolith from our interior Pb analyses.

Cirlin, E. H.↗

NASA NTRS1989

Minutes of the CD-ROM Workshop

The workshop described in this document had two goals: (1) to establish guidelines for the CD-ROM as a tool to distribute datasets; and (2) to evaluate current scientific CD-ROM projects as an archive. Workshop attendees were urged to coordinate with European groups to develop CD-ROM, which is already available at low cost in the U.S., as a distribution medium for astronomical datasets. It was noted that NASA has made the CD Publisher at the National Space Science Data Center (NSSDC) available to the scientific community when the Publisher is not needed for NASA work. NSSDC's goal is to provide the Publisher's user with the hardware and software tools needed to design a user's dataset for distribution. This includes producing a master CD and copies. The prerequisite premastering process is described, as well as guidelines for CD-ROM construction. The production of discs was evaluated. CD-ROM projects, guidelines, and problems of the technology were discussed.

King, Joseph H.↗

NASA NTRS1992

The distribution of cD galaxy peculiar velocities

A modified version of a cluster evolution computer code first described in Richstone and Malumuth (1983) and Malumuth and Richstone (1984) to investigate the distributon of cD galaxy peculiar velocities and positions relative to the center, for a sample of cDs formed through mergers in a virialized cluster. This distribution is compared to an observed distribution of 19 cD galaxies to test whether cD galaxies with large peculiar velocities could have been formed in virialized clusters. At the time of their formation the cD galaxies have a distribution of peculiar velocities similar to that of the observed cD galaxies. By the end of the simulations the cD galaxies were dragged to the center of the cluster by dynamical friction, and the distribution of peculiar velocities is inconsistent with the observed distribution. The typical cD galaxy has nine mergers and is 5 solar luminosities. This is in comparison with the observed luminosity of Morgan poor clusters of 7 solar luminosities.

Malumuth, Eliot M.↗

NASA NTRS2005

Composition-Temperature-Partial Pressures Data for Cd(sub 0.8)Zn(sub 0.2)Te by Optical Absorption Measurements

Known weights of Cd, Zn and Te were reacted in silica optical cells of known volume and the partial pressure of Te2 and Zn between 485 and 1160 C were determined by measuring the optical density of the vapor in the ultra-violet to visible range. The composition of the condensed phase or phases was calculated from the original weights and the amount of material in the vapor phase. The corresponding composition - temperature - partial pressures, x(sub Te)-T-P(sub Te2), data, including five Te-rich solidus points, were established. The solubility range for the Te-rich Cd(sub 0.8)Zn(sub 0.2)Te(s) is similar to that of CdTe(s) with x(sub Te) = 0.50005 at 809 C and an estimated maximum solubility of x(sub Te) = 0.50012 at about 1000 C. The partial pressure of Cd and Te(sub 2) measured over the Cd(sub 0.8)Zn(sub 0.2)Te melt at 1140 C were about 1.55 and 0.02 atm, respectively, and the corresponding P(Sub Zn) was estimated to be 0.05 atm. It was recommended that a Cd reservoir maintaining at 800 to 820 C should be used during directional solidification of Cd(sub o.8)Zn(sub 0.2)Te to prevent the preferential loss of Cd to the vapor phase.

Su, Ching-Hua↗

DOE OSTI2020

Materials Data on Cd(PO4)2 by Materials Project

Cd(PO4)2 crystallizes in the trigonal P-3 space group. The structure is three-dimensional. Cd is bonded to six O atoms to form CdO6 octahedra that share corners with four equivalent PO4 tetrahedra. There are a spread of Cd–O bond distances ranging from 2.25–2.51 Å. P is bonded to four O atoms to form PO4 tetrahedra that share corners with two equivalent CdO6 octahedra and corners with two equivalent PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 44–51°. There are a spread of P–O bond distances ranging from 1.49–1.63 Å. There are four inequivalent O sites. In the first O site, O is bonded in a bent 120 degrees geometry to two equivalent P atoms. In the second O site, O is bonded in a distorted bent 120 degrees geometry to one Cd and one P atom. In the third O site, O is bonded in a distorted bent 150 degrees geometry to one Cd and one P atom. In the fourth O site, O is bonded in a single-bond geometry to one Cd atom.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on Cd(BrO2)2 by Materials Project

Cd(O2Br)2 crystallizes in the orthorhombic Pnnm space group. The structure is three-dimensional. Cd is bonded in a distorted linear geometry to two equivalent O and four equivalent Br atoms. Both Cd–O bond lengths are 2.16 Å. All Cd–Br bond lengths are 2.97 Å. There are two inequivalent O sites. In the first O site, O is bonded in a distorted single-bond geometry to two equivalent O and one Br atom. Both O–O bond lengths are 1.94 Å. The O–Br bond length is 1.97 Å. In the second O site, O is bonded in a 2-coordinate geometry to one Cd, two equivalent O, and one Br atom. The O–Br bond length is 2.13 Å. Br is bonded in a 2-coordinate geometry to two equivalent Cd and two O atoms.

36 MATERIALS SCIENCE↗

DOE OSTI2021

A combined management scheme to simultaneously mitigate As and Cd concentrations in rice cultivated in contaminated paddy soil

Paddy soils in southern China are heavily co-polluted by arsenic (As) and cadmium (Cd). The accumulation of these contaminants in rice grains may pose a high health risk. We evaluated the impact of adjusted water management practice (i.e., conventional irrigation and aerobic treatment after heading stage) and the application of two immobilization agents (i.e., CaO and Fe2O3) on the accumulation of As and Cd in rice grains of three rice varieties (i.e., Jinyou-463, Jinyou-268, and Mabayouzhan). The different schemes were tested via conducting a field experiment in paddy soil in Shaoguan, Guangdong Province, China. The results showed that the combined scheme (selecting Jinyou-268, aerobic water management after the heading stage, and 0.09% CaO and 0.5% Fe2O3 amendments) exhibited the best performance in the reduction of As and Cd accumulation in rice grains. This combined scheme decreased the grain As concentration by 26.19% and maintained the Cd at a low level (0.056 mg/kg) as compared to the use of local conventional irrigation patterns. Moreover, health risk assessment demonstrated that by applying the optimal scheme, neither As nor Cd content in rice had carcinogenic risk. However, the grain As remains at a high non-carcinogenic risk. We suggest that future field study design should fully incorporate the uncertainty of the natural environment to make the research conclusions more feasible for popularization and utilization. This study demonstrated an approach of utilizing the synergy effects of various measures for safe rice production in fields subjected to As and Cd contaminations.

Yang, Xiao↗