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IN2 is High Pressure Cadmuum Telluride structured and crystallizes in the tetragonal I4/mcm space group. The structure is two-dimensional and consists of four nitrogen molecules and two I sheets oriented in the (0, 0, 1) direction. In each I sheet, I1- is bonded in a square co-planar geometry to four equivalent I1- atoms. All I–I bond lengths are 3.45 Å.
P(Br)2 is High Pressure Cadmuum Telluride structured and crystallizes in the tetragonal P4/mmm space group. The structure is zero-dimensional and consists of one bromine molecule and one phosphine molecule.
HgTl2Te is Cyanogen Chloride-like structured and crystallizes in the orthorhombic Immm space group. The structure is zero-dimensional and consists of two mercury molecules and two thallium telluride molecules.
GeSb is High Pressure Cadmuum Telluride structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Ge3+ is bonded in a linear geometry to two equivalent Sb3- atoms. Both Ge–Sb bond lengths are 2.93 Å. Sb3- is bonded to two equivalent Ge3+ and four equivalent Sb3- atoms to form a mixture of edge and corner-sharing SbGe2Sb4 octahedra. The corner-sharing octahedral tilt angles are 0°. All Sb–Sb bond lengths are 2.94 Å.
Nb5(SeS)2 is Titanium telluride-derived structured and crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are three inequivalent Nb sites. In the first Nb site, Nb is bonded in a distorted square co-planar geometry to two equivalent Se and two equivalent S atoms. Both Nb–Se bond lengths are 2.88 Å. Both Nb–S bond lengths are 2.73 Å. In the second Nb site, Nb is bonded to two equivalent Se and three equivalent S atoms to form distorted NbSe2S3 square pyramids that share corners with eight equivalent NbSe3S2 square pyramids and edges with six NbSe2S3 square pyramids. Both Nb–Se bond lengths are 2.66 Å. There are one shorter (2.50 Å) and two longer (2.59 Å) Nb–S bond lengths. In the third Nb site, Nb is bonded to three equivalent Se and two equivalent S atoms to form a mixture of distorted edge and corner-sharing NbSe3S2 square pyramids. There are one shorter (2.63 Å) and two longer (2.72 Å) Nb–Se bond lengths. Both Nb–S bond lengths are 2.54 Å. Se is bonded in a 6-coordinate geometry to six Nb atoms. S is bonded in a 6-coordinate geometry to six Nb atoms.
InSb is High Pressure Cadmuum Telluride structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. In3+ is bonded in a linear geometry to two equivalent Sb3- atoms. Both In–Sb bond lengths are 3.11 Å. Sb3- is bonded to two equivalent In3+ and four equivalent Sb3- atoms to form a mixture of edge and corner-sharing SbIn2Sb4 octahedra. The corner-sharing octahedral tilt angles are 0°. All Sb–Sb bond lengths are 3.08 Å.
(YbTe)2Te crystallizes in the tetragonal P4/mmm space group. The structure is zero-dimensional and consists of one tellurium molecule and two ytterbium telluride molecules.
SnSb is High Pressure Cadmuum Telluride structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Sn2+ is bonded in a linear geometry to two equivalent Sb2- atoms. Both Sn–Sb bond lengths are 3.13 Å. Sb2- is bonded to two equivalent Sn2+ and four equivalent Sb2- atoms to form a mixture of edge and corner-sharing SbSn2Sb4 octahedra. The corner-sharing octahedral tilt angles are 0°. All Sb–Sb bond lengths are 3.07 Å.
V5Se4 is Titanium telluride structured and crystallizes in the tetragonal I4/m space group. The structure is three-dimensional. there are two inequivalent V sites. In the first V site, V is bonded in a distorted square co-planar geometry to four equivalent Se atoms. All V–Se bond lengths are 2.65 Å. In the second V site, V is bonded to five equivalent Se atoms to form a mixture of distorted corner and edge-sharing VSe5 square pyramids. There are a spread of V–Se bond distances ranging from 2.48–2.53 Å. Se is bonded in a 6-coordinate geometry to six V atoms.
CdSb is High Pressure Cadmuum Telluride structured and crystallizes in the orthorhombic Pmmm space group. The structure is three-dimensional. Cd2+ is bonded in a distorted rectangular see-saw-like geometry to four equivalent Sb2- atoms. All Cd–Sb bond lengths are 3.18 Å. Sb2- is bonded to four equivalent Cd2+ and four equivalent Sb2- atoms to form a mixture of distorted edge and corner-sharing SbCd4Sb4 hexagonal bipyramids. There are two shorter (3.11 Å) and two longer (3.24 Å) Sb–Sb bond lengths.
This document outlines a set of requirements for gamma sensitive systems applied to three different applications: (1) homeland security (search and identification); (2) in-situ quantification; and (3) quantification in a material characterization laboratory. These three applications represent a range of activities that a country might use for locating, identifying, and quantifying radioactive material. These applications require increasing accuracy and system advancements, and skill levels. This document considers systems with various detector types and are characterized by their energy resolution: (1) low resolution (e.g., NaI(Tl) scintillation) and (2) higher resolution (e.g., high-purity germanium [HPGe] solid state) systems. The higher resolution systems also include cadmium zinc telluride (CZT) and only mechanically cooled HPGe systems are considered. These detectors and their associated acquisition hardware and analysis software afford a broad range of capabilities with corresponding ranges of complexity, maintainability, and cost. Ultimately, the equipment must meet the measurement goals of the application, and compliance with a given list of hardware specifications does not in itself guarantee meeting those goals. Examples of typical performance objectives for international safeguards applications are documented in International Target Values 2010 for Measurement Uncertainties in Safeguarding Nuclear Materials (IAEA, STR-368, November 2010). Selection of the detector type best suited to a specific application is often a compromise between “state of the art” or best available option and what is practical.
The use of Acidithiobacillus ferrooxidans, Thiobacillus thiooxidans, and other chemoautotrophic microbes in bioleaching have been implemented in a variety of processes.1 In industry, bioleaching has been studied for its potential to extract valuable metals from low grade ores that would otherwise be cost prohibitive to recover.2 Other applications of bioleaching include the ability of certain microbes to detoxify waste products and even heavy metal contaminated soils.3 Another potential application for such bio-oxidative microbial activity is the extraction of tellurium (Te) from mine tailings, a low-cost abundant resource. Tellurium is one of the least common elements on Earth; it is found in the planetary crust at about 1 µg/kg, a rarity most comparable to that of platinum.4 A major use of Te in the U.S. is in cadmium-telluride (CdTe) solar panels5. Te is primarily imported into the U.S. from Canada, and it is usually recovered as a byproduct of copper refining.6 Since CdTe photovoltaic (PV) cells are the most efficient, cost-effective, and environmentally friendly PV chemistry, the renewables market has seen an increased demand for CdTe PV cells causing some concerns about sustainability and the limited global availability of Te. Acidithiobacillus ferroxidans is a microorganism that can oxidize iron and sulfur to produce ferric iron and sulfuric acid, and it is possible that it could also solubilize Te from sulfidic mine tailings. In this project, different media for growth of A. ferroxidans were evaluated, and a plan for testing the ability of A. ferroxidans to leach Te from mine tailings was developed. Initial characterization of A. ferroxidans cultures grown in the presence of copper tailings suggests that conditions suitable for Te bioleaching can be established.
Brookhaven National Laboratory (BNL) worked with FLIR System Inc., the manufacturer of the nanoRAIDER, to develop a handheld field deployable detector based on the novel position-sensitive virtual Frisch-grid (VFG) Cadmium-Zinc-Telluride (CdZnTe or CZT) detectors (with 1% FWHM at 662 keV or better energy resolution). The detector called nanoRAIDER-VFG would be an improvement to the current nanoRAIDER, which is a compact gamma-ray detection instrument manufactured by FLIR Systems Inc. that employs relatively lower-performing CZT hemispheric detectors (i.e., 3%-FWHM CZT detectors). The nanoRAIDER-VFG would have significantly improved accuracy of measurements while maintaining similar efficiency, as compared to the nanoRAIDER, for in-field analysis of nuclear materials and detection of undeclared activities during inspections conducted by the International Atomic Energy Agency (IAEA). Since the nanoRAIDER is currently used by the IAEA as part of its Complementary Access toolkit, a relatively quick acceptance of the nanoRAIDER-VFG for safeguards was anticipated. The nanoRAIDER-VFG project was undertaken to address the following items in the IAEA's Long-Term R&D Plan, 2012-2023: 2.2 (elemental and isotopic signatures of fuel cycle processes); 2.3 (detect signatures of undeclared activity and improve analysis); and 2.6 (detect process emanations). The high energy-resolution of the nanoRAIDER-VFG would also have had applicability to 3.2 (fissile content of metal mixtures containing actinides Np, Am, etc.). The project was not completed due to a change in priorities within FLIR.
This thesis presents the first observation of the production of three massive vector bosons (VVV with V = W, Z) in proton-proton collisions at the LHC at $\sqrt{s}=13\text{ TeV}$. The search was performed in final states with two same-sign charged leptons (electrons or muons) plus one or two jets, and three, four, five, or six leptons from WWW, WWZ, WZZ and ZZZ decays, with a data sample corresponding to an integrated luminosity of 137 fb -1 collected by the CMS experiment during 2016-2018. The observed (expected) significance of the combined VVV production is 5.7 (5.9) standard deviations, and the production cross section is measured to be 1010$^{+210}_{-200}$(stat) $^{+150}_{-120}$(syst) fb, corresponding to a signal strength of 1.02$^{+0.26}_{-0.23}$. We also found evidence for WWW and for WWZ production, with observed significances of 3.3 and 3.4 standard deviations, respectively. The measured production cross sections for individual VVV processes are also reported. The establishment of VVV production opens a new program of many standard model studies (such as gauge-gauge and Higgs-gauge couplings), and provides a new tool for many new physics searches (such as anomalous gauge coupling searches, new resonance searches). This thesis also reports a search for long-lived supersymmetry particles decaying to photons in proton-proton collisions at the LHC at $\sqrt{s} = 13 TeV$, with a data sample corresponding to an integrated luminosity of 77.4 fb -1 collected by CMS during 2016-2017. Results are interpreted with a gauge-mediated supersymmetry breaking model, where the long-lived particle is a neutralino and the lightest supersymmetry particle is a gravitino. For neutralino proper decay lengths of 0.1, 1, 10, and 100 m, masses up to 320, 525, 360, and 215 GeV are excluded at 95% confidence level, respectively. This result extends the limits from previous searches by one order of magnitude for the neutralino proper decay length and up to 100 GeV more for the neutralino mass. Motivated by the need for precision timing measurements for long-lived particle searches, as well as for improvements in general object reconstruction performance, the timing performance of two types of sensors are studied in this thesis: one with a Cerium doped Lutetium Yttrium Orthosilicate (LYSO:Ce) crystal as the scintillator and a silicon photomultiplier (SiPM) as the photodetector, another with a Cadmium-Telluride sensor as the active material for a sampling calorimeter. Both setups have been demonstrated with test beams to be able to provide timing measurements of particles with a resolution below 30 ps.
This report benchmarks 2020 PV module minimum sustainable price (MSP) via bottom-up manufacturing cost analysis, for established PV technologies in mass production, including crystalline silicon, cadmium telluride (CdTe), and copper indium gallium (di)selenide. We provide technology roadmaps to additional MSP reductions for these PV technologies. Separately, we consider III-V and perovskite PV technologies which are currently in small-scale or pilot production. Finally, this report uses a technology evolution framework (TEF) to analyze drivers of levelized cost of energy reductions, including installed system cost - which is heavily influenced by module price - as well as service life and annual energy yield.
Our benchmarking method includes bottom-up accounting for all necessary system and projectdevelopment costs incurred when installing residential, commercial, and utility-scale systems, and it models the Q1 2021 costs for such systems, excluding any previous supply agreements or contracts. In general, we attempt to model the typical installation techniques and business operations from an installed-cost perspective, and our benchmarks are national averages. The residential PV-only benchmark and the commercial rooftop PV-only benchmark average costs by inverter type (string inverters, string inverters with direct current [DC] optimizers, and microinverters), weighted by inverter market share. The residential PV-only benchmark is further averaged across small installer and national integrator business models, weighted by market share. All benchmarks include variations—accounting for the differences in size, equipment, and operational use (particularly for storage)—that are currently available in the marketplace. All benchmarks assume nonunionized construction labor; residential and commercial PV systems predominantly use nonunionized labor, and the type of labor required for utility-scale PV systems depends heavily on the development process. All benchmarks assume the use of monofacial monocrystalline silicon PV modules. Benchmarks using cadmium telluride or bifacial modules could result in significantly different results. The data in this annual benchmark report inform the formulation of and track progress toward the U.S. Department of Energy (DOE) Solar Energy Technologies Office’s Government Performance and Reporting Act cost targets.
Photocathode (alkali antimonides & tellurides) thin film growth state of the art remains largely an art of “cooking” instead of a controlled technological process. Our technology is a method of growing thin films by molecular beam deposition, that applies specifically to photoemissive films. We discovered that some of the photoemissive properties of Cs3Sb (easily measurable) strongly depend on the film’s stoichiometry (very difficult to measure, especially in real time). Such correlation allows to implement a feedback loop that adjusts the ratio of Cs and Sb fluxes in real time and thus maintains the same stoichiometric composition of the film during the whole growth cycle that may last for hours/days. Proposed scheme constitutes true, robust and versatile process control for the growth of alkali antimonide thin films.
The project synthesized and made transport properties of topological crystalline insulator tin telluride (SnTe) nanowires and other topological materials, such as MoTe 2 and WTe 2 . The transport properties of the nanowires were correlated with the diameter of the nanowire, in terms of the ferroelectric phase transition temperature, magnetoresistance response, and Josephson junction behaviors as a function of the nanowire diameter. The most important observation was the proximity-induced superconductivity in SnTe nanowires, which suggests time reversal symmetry breaking.