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The 1996 evaluation for the A=127 mass chain (1996Ki01) has been revised. The experimental results from various decays and reactions for the A=127 mass chain have been compiled and evaluated. The nuclides covered in this evaluation are from {sup 127}Ag to {sup 127}Nd. The data are summarized and presented, together with adopted level schemes.
The (d, p) reaction was measured with the radioactive ion beams of {sup 126}Sn and {sup 128}Sn in inverse kinematics at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory, utilizing the Super ORRUBA silicon detector array. Angular distributions of reaction protons were measured for several states in {sup 127}Sn and {sup 129}Sn to determine angular momentum transfers and deduce spectroscopic factors. Such information is critical for calculating direct (n,{gamma}) cross sections for the r-process as well as for constraining shell model parameters in the A Almost-Equal-To 130 region. Combined with previous experiments on {sup 130}Sn and {sup 132}Sn, these results will provide a complete set of (d, p) reaction data on even tin isotopes between stable {sup 124}Sn and doubly-magic {sup 132}Sn.
Purpose: Gold nanoparticles (AuNP) are multifunctional platforms ideal for drug delivery, targeted imaging and radiosensitization. We have investigated quantitative imaging of AuNPs using on board imager (OBI) cone beam computed tomography (CBCT). To this end, we also present, for the first time, a novel method for k-edge imaging of AuNP by filter-based spectral shaping. Methods: We used a digital 25 cm diameter water phantom, embedded with 3 cm spheres filled with AuNPs of different concentrations (0 mg/ml – 16 mg/ml). A poly-energetic X-ray spectrum of 140 kVp from a conventional X-ray tube is shaped by balanced K-edge filters to create an excess of photons right above the K-edge of gold at 80.7 keV. The filters consist of gold, tin, copper and aluminum foils. The phantom with appropriately assigned attenuation coefficients is forward projected onto a detector for each energy bin and then integrated. FKD reconstruction is performed on the integrated projections. Scatter, detector efficiency and noise are included. Results: We found that subtracting the results of two filter sets (Filter A:127 µm gold foil with 254 µm tin, 330 µm copper and 1 mm aluminum, and Filter B: 635 µm tin with 264 µm copper and 1 mm aluminum), provides substantial image contrast. The resulting filtered spectra match well below 80.7 keV, while maintaining sufficient X-ray quanta just above that. Voxel intensities of AuNP containing spheres increase linearly with AuNP concentration. K-edge imaging provides 18% more sensitivity than the tin filter alone, and 38% more sensitivity than the gold filter alone. Conclusion: We have shown that it is feasible to quantitatively detect AuNP distributions in a patient-sized phantom using clinical CBCT and K-edge spectral shaping.
Excited states of {sup 127}I were populated via {sup 124}Sn({sup 7}Li,{sup 4}nγ){sup 127}I fusion-evaporation reaction at beam energy of 33 MeV. Multipolarities of several transitions were determined and spins of corresponding states have been confirmed. The band-head spin and parity of an already reported band at 2901.2 keV has been confirmed. Based on the observed characteristic features and by comparing with the systematics of odd mass iodine nuclei, a πg{sub 7/2}⊗νh{sub 11/2}{sup 2} configuration has been proposed for this band. The experimental B(M1)/B(E2) values for πg{sub 7/2} band were compared with the theoretical results of semi classical model of Frauendorf and Donau and found in well agreement.
Precise mass measurements of the neutron-rich 125–130 In isotopes have been performed with the TITAN Penning trap mass spectrometer. TITAN's electron beam ion trap was used to charge breed the ions to charge state q = 13+ thus providing the necessary resolving power to measure not only the ground states but also isomeric states at each mass number. Here, the properties of the ground states are investigated through a series of mass differentials, highlighting trends in the indium isotopic chain as compared to its proton-magic neighbor, tin (Z = 50). In addition, the energies of the indium isomers are presented. The (8 - ) level in 128 In is found to be 78 keV lower than previously thought and the (21/2 - ) isomer in 127 In is shown to be lower than the literature value by more than 150 keV.
The temperature-dependent structure evolution of the hybrid halide perovskite compounds, formamidinium tin iodide (FASnI 3 , FA + = CH[NH 2 ] 2 + ) and formamidinium lead bromide (FAPbBr 3 ), has been monitored using high-resolution synchrotron X-ray powder diffraction between 300 and 100 K. The data are consistent with a transition from cubic Pm$\bar{3}$m (No. 221) to tetragonal P 4 /mbm (No. 127) for both materials upon cooling; this occurs for FAPbBr 3 between 275 and 250 K, and for FASnI 3 between 250 and 225 K. Upon further cooling, between 150 and 125 K, both materials undergo a transition to an orthorhombic Pnma (No. 62) structure. The transitions are confirmed by calorimetry and dielectric measurements. In the tetragonal regime, the coefficients of volumetric thermal expansion of FASnI 3 and FAPbBr 3 are among the highest recorded for any extended inorganic crystalline solid, reaching 219 ppm K –1 for FASnI 3 at 225 K. Atomic displacement parameters of all atoms for both materials suggest dynamic motion is occurring in the inorganic sublattice due to the flexibility of the inorganic network and dynamic lone pair stereochemical activity on the B-site. Unusual pseudocubic behavior is displayed in the tetragonal phase of the FAPbBr 3 , similar to that previously observed in FAPbI 3 .
The (d,p) reaction was measured with radioactive ion beams of 126Sn and 128Sn (~5 MeV/u) in inverse kinematics at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory, utilizing the SuperORRUBA silicon detector array. Angular distributions of reaction protons were measured for several states in 127Sn and 129Sn in order to determine angular momentum transfers and deduce spectroscopic factors. Combined with previous experiments on 130Sn and 132Sn, these results provide a complete set of (d,p) reaction data on even tin isotopes between stable 124Sn and doubly magic 132Sn.
A large new family of rare-earth metal-cadmium-germanides RE{sub 2}CdGe{sub 2} (RE=Y, Pr, Nd, Sm, Gd-Yb) has been synthesized and structurally characterized. All eleven structures have been established from single-crystal X-ray diffraction data and have been found to belong to the tetragonal Mo{sub 2}FeB{sub 2} structure type (ordered ternary variant of the U{sub 3}Si{sub 2} structure type-space group P4/mbm (No. 127), Z=2; Pearson symbol tP10). The structural variations among the three series of isostructural RE{sub 2}MgGe{sub 2}, RE{sub 2}InGe{sub 2}, and RE{sub 2}CdGe{sub 2} compounds are discussed, as well as the crystal chemistry changes as a function of the decreasing size of the rare-earth metals (lattice constants a=7.176(2)-7.4589(12) A and c=4.1273(14)-4.4356(13) A). The experimental results have been complemented by tight-binding linear muffin-tin orbital (TB-LMTO) electronic structure calculations. - Graphical abstract: More than 300 compounds have been reported to crystallize with the tetragonal U{sub 3}Si{sub 2} structure type, or the Mo{sub 2}FeB{sub 2} structure type, which is its ordered ternary variant. Among them, there are several large RE{sub 2}CdX{sub 2} classes, where the X-elements are typically late transition metals such as Cu, Ni, Au, Pd, Pt, and Rh. The new RE{sub 2}CdGe{sub 2} phases (RE=Y, Pr, Nd, Sm, Gd-Yb) increase the diversity and represent the first cadmium germanides. Highlights: Black-Right-Pointing-Pointer RE{sub 2}CdGe{sub 2} (RE=Y, Pr, Nd, Sm, Gd-Yb) are new ternary germanides. Black-Right-Pointing-Pointer Their structures can be recognized as a 1:1 intergrowth of CsCl- and AlB{sub 2}-like slabs. Black-Right-Pointing-Pointer The Ge atoms are covalently bound into Ge{sub 2} dumbbells. Black-Right-Pointing-Pointer Almost all RE{sub 2}CdGe{sub 2} phases are the first structurally characterized phases in the respective ternary RE-Cd-Ge systems.
We report the Na-Au-Zn system contains the two intermetallic phases Na 0.97(4) Au 2 Zn 4 (I) and Na 0.72(4) Au 2 Zn 2 (II) that are commensurately and incommensurately modulated derivatives of K 0.37 Cd 2 , respectively. Compound I crystallizes in tetragonal space group P 4 /mbm (No. 127), a = 7.986(1) Å, c = 7.971(1) Å, Z = 4, as a 1 × 1 × 3 superstructure derivative of K 0.37 Cd 2 (I 4 /mcm). Compound II is a weakly incommensurate derivative of K 0.37 Cd 2 with a modulation vector q = 0.189(1) along c. Its structure was solved in superspace group P4 /mbm(00g)00ss, a = 7.8799(6) Å, c = 2.7326(4) Å, Z = 2, as well as its average structure in P4/mbm with the same lattice parameters.. The Au-Zn networks in both consist of layers of gold or zinc squares that are condensed antiprismatically along c ([Au 4/2 Zn 4 Zn 4 Au 4/2 ] for I and [Au 4/2 Zn 4 Au 4/2 ] for II) to define fairly uniform tunnels. The long-range cation dispositions in the tunnels are all clearly and rationally defined by electron density (Fourier) mapping. These show only close, somewhat diffuse, pairs of opposed, ≤50% occupied Na sites that are centered on (I)(shown) or between (II) the gold squares. Tight-binding electronic structure calculations via linear muffin-tin-orbital (LMTO) methods, assuming random occupancy of ≤ ~100% of nonpaired Na sites, again show that the major Hamilton bonding populations in both compounds arise from the polar heteroatomic Au-Zn interactions. Clear Na-Au (and lesser Na-Zn) bonding is also evident in the COHP functions. These two compounds are the only stable ternary phases in the (Cs,Rb,K,Na)-Au-Zn systems, emphasizing the special bonding and packing requirements in these sodium structures