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DOE OSTI2023

Low-Voltage Haze Tuning with Cellulose-Network Liquid Crystal Gels

Being key components of the building envelope, glazing products with tunable optical properties are in great demand because of their potential for boosting energy efficiency and privacy features while enabling the main function of allowing natural light indoors. However, windows and skylights with electric switching of haze and transparency are rare and often require high voltages or electric currents, as well as not fully meet the stringent technical requirements for glazing applications. Here, by introducing a predesigned gel material we describe an approach dubbed “Haze-Switch” that involves low-voltage tuning of the haze coefficient in a broad range of 2–90% while maintaining high visible-range optical transmittance. The approach is based on a nanocellulose fiber gel network infiltrated by a nematic liquid crystal, which can be switched between polydomain and monodomain spatial patterns of optical axis via a dielectric coupling between the nematic domains and the applied external electric field. By utilizing a nanocellulose network of nanofibers ~10 nm in diameter we achieve <10 V dielectric switching and <2% haze in the clear state, as needed for applications in window products. Finally, we characterize physical properties relevant to window and smart glass technologies, like the color rendering index, haze coefficient, and switching times, demonstrating that our material and envisaged products can meet the stringent requirements of the glass industry, including applications such as privacy windows, skylights, sunroofs, and daylighting.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2013

Low Cost Electrochromic Film on Plastic for Net-Zero Energy Buildings

Over 4 Quads of energy are lost through windows annually. Passive coatings reduce wasted energy, but energy lost through windows would remain over 2 Quads with complete replacement of Low-E glass. Active control of transmitted light and solar heating with electrochromic (EC) windows can transform the efficiency of energy use within buildings, thereby reducing energy footprints and corresponding greenhouse emissions. High production, integration, and distribution cost limits adoption of current EC products. ITN aimed to utilize its proven heritage of efficiently transitioning technologies from rigid to flexible substrates employing roll-to-roll manufacturing to capture the emerging EC window market opportunity. The project focused on three main efforts (1) Transition Small Scale Prototypes To Limited 0.5 Meter Wide, Web Coater Production, (2) Satisfy Market Driven EC Performance Metrics on Plastic Substrates, and (3) Product Development and Commercialization. The overall goal was to substantially reduce investor risk to motivate private investment in a production facility to further transition and scale this promising technology. A 0.5 meter roll-to-roll web coater was designed, constructed, and commissioned at ITN to support EC development effort. With this tool, we were able to establish the feasibility of roll-to-roll production of EC devices. Individually layers were continuously produced at lengths up to 3 meters with good uniformity, both down web and cross web. Solid state devices were produced, and device performance was being enhanced through hardware modifications underway at the close of the project. When deployed in composite device structures, we were able to verify that individual layers were able to achieve a transmission range of 3-70% transmission average over the visible portion of the spectrum. Initial development of intelligent process controls led to verification of a 2-state controller employed during deposition of the electrochromic layer. The project also successfully increased device performance in line with market needs. Improved device materials provided increased transmission range to a 5-65% transmission over the visible spectrum and faster switching times for both small area batch parts and large area composite materials. We were able to demonstrate durable cycling over 10,000-20,000 cycles in a variety of architectures including suspended films in an IGU and films laminated to glass tested in open air representative of retrofit applications. Robust packaging techniques were identified and samples proved durable even in 40C and 100% relative humidity outside the IGU environment.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2020

Evaluation of Exterior Shades at PNNL Lab Homes and Occupied Field Sites (Final Report)

In residential applications, heat transfer through windows accounts for a significant portion of a home’s cooling load. Exterior shades are window attachments that can be applied on the exterior-side of windows in a home. Exterior shades can reduce solar heat gain, reduce glare through a window, and improve comfort in the home. To assess the performance of residential exterior shades, the U.S. Department of Energy (DOE), Office of Energy Efficiency and Renewable Energy (EERE), Building Technologies Office (BTO) commissioned a series of field studies for exterior fabric shades to be performed by Pacific Northwest National Laboratory (PNNL) during the cooling seasons of 2019 and 2020. This report describes the experimental setup and results of these exterior shade field studies. PNNL, in collaboration with Lawrence Berkeley National Laboratory (LBNL), evaluated exterior shades at the PNNL Lab Homes and three occupied field sites in Richland, Washington. At the Lab Homes, the energy performance of exterior shades was evaluated in a controlled side-by-side environment. At the occupied field sites, exterior shades were characterized by measuring shade usage, documenting installation practices, and surveying customer perspectives.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

NASA NTRS2024

Residual Strength of Hypervelocity Impacted Silica

Windows in the International Space Station (ISS) are subject to ongoing micrometeoroid and orbital debris (MMOD) damage. The reliability of the windows is ensured by monitoring of damage, life prediction, and measurement of the residual strength of man-made and natural hypervelocity impacted window materials. Information on the residual strength of man-made craters and MMOD craters harvested from space shuttle windows was used to estimate strength as a function of damage dimensions and thereby derive design allowables for U.S. and Russian fused silicas used in the ISS. An effect of impact angle is apparent, with 0° impacts exhibiting the lowest strength for Russian quartz-derived silica. The crater morphology for fused silica consists of a central pit, crush zone, shallow rings, and radial cracks dividing shallow, petal-like lateral cracks (petaloids). The morphology of alkaline glass differs from that of fused silica, with a more distinct pit and pulverized region, and bell-shaped and tail-like features below the pit.

International space station,↗

DOE OSTI2018

MXene-Conducting Polymer Asymmetric Pseudocapacitors

Conducting polymers (CPs) are attractive pseudocapacitive materials which show the highest capacitance under positive potentials in aqueous protic electrolytes. One way to expand their voltage window (thus energy density) in aqueous electrolytes is to manufacture asymmetric supercapacitors using distinctly different anodes. However, CPs lack matching pseudocapacitive anode materials that can perform well in protic electrolytes (e.g., sulfuric acid). 2D titanium carbide (Ti 3 C 2 T x ), MXene, as a universal pseudocapacitive anode material for a range of CPs, such as polyaniline, polypyrrole, and poly(3,4-ethylenedioxythiophene) deposited on reduced graphene oxide (rGO) sheets, is reported here. All-pseudocapacitive organic–inorganic asymmetric devices with MXene cathodes and rGO–polymer anodes can operate in voltage windows up to 1.45 V in 3 m H 2 SO 4 . Most importantly, these devices show outstanding cycling performance, outperforming many reported asymmetric pseudocapacitors.

catalysis (heterogeneous)↗

DOE OSTI2023

Vanadium and Niobium MXenes—Bilayered V 2 O 5 Asymmetric Supercapacitors

MXenes offer high metallic conductivity and redox capacitance that are attractive for high-power, high-energy storage devices. However, they operate limitedly under high anodic potentials due to irreversible oxidation. Pairing them with oxides to design asymmetric supercapacitors may expand the voltage window and increase the energy storage capabilities. Hydrated lithium preintercalated bilayered V 2 O 5 ( δ-Li x V 2 O 5 ·nH 2 O) is attractive for aqueous energy storage due to its high Li capacity at high potentials; however, its poor cyclability remains a challenge. To overcome its limitations and achieve a wide voltage window and excellent cyclability, it is combined with V 2 C and Nb 4 C 3 MXenes. Asymmetric supercapacitors employing lithium intercalated V 2 C (Li-V 2 C) or tetramethylammonium intercalated Nb 4 C 3 (TMA-Nb 4 C 3 ) MXenes as the negative electrode, and a δ-Li x V 2 O 5 ·nH 2 O composite with carbon nanotubes as the positive electrode in 5 m LiCl electrolyte operate over wide voltage windows of 2 and 1.6 V, respectively. The latter shows remarkably high cyclability—capacitance retention of ≈95% after 10 000 cycles. Here, this work highlights the importance of selecting appropriate MXenes to achieve a wide voltage window and a long cycle life in combination with oxide anodes to demonstrate the potential of MXenes beyond Ti 3 C 2 in energy storage.

36 MATERIALS SCIENCE↗

DOE OSTI2019

Extreme Events and Climate Adaptation-Mitigation Linkages: Understanding Low-Carbon Transitions in the Era of Global Urbanization

It has become increasingly clear that cities will have to simultaneously undertake both adaptation and mitigation in response to accelerating climate change and the growing demands for meaningful climate action. Here we examine the connections between climate mitigation and climate adaptation, specifically, between low-carbon energy systems and extreme events. The article specifically addresses the question, how do responses to extreme climate risks enhance or limit capacity to promote city-level greenhouse gas (GHG) mitigation? As a step toward answering this question, we present a framework for considering windows of opportunity that may arise as a result of extreme events and how these windows can be exploited to foster development and implementation of low-carbon energy strategies. Four brief case studies are used to provide empirical background and determine the impact of potential windows of opportunity. Some general conclusions are defined. In particular, the existing energy system structure is an important determinant of impact and potential for energy transitions. Well-developed and articulated governance strategies and ready access of effective and economically efficient alternative energy technology were key to transitions. However, prospects for inequity in development and implementation of low-carbon solutions need to be considered. Finally, exploiting windows of opportunity afforded by extreme events for developing low-carbon economy and infrastructure also can provide resilience against those very events. These types of responses will be needed as extreme events increase in frequency and magnitude in the future, with cities as primary sites of impact and action.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

DOE OSTI2018

Higgs and Z assisted stop searches at hadron colliders

Current searches for the light top squark (stop) mostly focus on the decay channels of $ \tilde{t}\to t{\chi}_1^0 $ or $ \tilde{t}\to b{\chi}_1^{\pm}\to bW{\chi}_1^0 $ , leading to Open image in new window final states for stop pair productions at the LHC. However, in supersymmetric scenarios with light neutralinos and charginos other than the neutralino lightest supersymmetric particle (LSP), more than one decay mode of the stop could be dominant. While those new decay modes could significantly weaken the current stop search limits at the LHC, they also offer alternative discovery channels for stop searches. In this paper, we studied the scenario with light Higgsino next-to-LSPs (NLSPs) and Bino LSP. The light stop decays primarily via $ {\tilde{t}}_1\to t{\chi}_2^0/{\chi}_3^0 $ , with the neutralinos subsequent decaying to a Z boson or a Higgs boson: χ 2° /χ 3 ° → χ 1 ° h/Z. Pair production of light stops at the LHC leads to final states of Open image in new window or Open image in new window . We consider three signal regions: one charged lepton (1ℓ), two opposite sign charged leptons (2 OS ℓ) and at least three charged leptons (≥3ℓ). We found that the 1ℓ signal region of channel Open image in new window has the best reach sensitivity for light stop searches. For 14 TeV LHC with 300 fb -1 integrated luminosity, a stop mass up to 900 GeV can be discovered at 5σ significance, or up to 1050 GeV can be excluded at 95% C.L. Combining all three decay channels for 1ℓ signal region extends the reach for about 100–150 GeV. We also studied the stop reach at the 100 TeV pp collider with 3 ab -1 luminosity, with discovery and exclusion reach being 6 TeV and 7 TeV, respectively.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2020

Optical Response of Soda-Lime Glass Shocked to 14 GPa

To investigate the potential use of soda-lime glass (SLG) as an optical window in shock wave experiments, laser interferometry (VISAR) was used to determine the window correction and the refractive index in SLG samples subjected to plane shock wave compression. Symmetric plate impact experiments were conducted at peak stresses varying between 4 and 14 GPa and laser interferometry ($λ_0$ = 532$\textit {nm}$ wavelength) measurements were used to monitor the particle velocity histories at the impact surface. The higher stress experiments displayed a constant state prior to stress unloading. In contrast, the lower stress experiments (4.3 and 7.8 GPa) displayed an initial constant state followed by weakly time-dependent response prior to stress unloading. Because the actual particle velocities were independently known from the projectile velocity measurements, the window correction factor and the refractive index changes were determined over the stress range examined. Above 7.5 GPa, our window correction and refractive index results show significant differences with previously published data for the same material. Potential reasons for these differences are indicated.

36 MATERIALS SCIENCE↗

DOE OSTI2015

Measured daylighting potential of a static optical louver system under real sun and sky conditions

Side-by-side comparisons were made over solstice-to-solstice changes in sun and sky conditions between an optical louver system (OLS) and a conventional Venetian blind set at a horizontal slat angle and located inboard of a south-facing, small-area, clerestory window in a full-scale office testbed. Daylight autonomy (DA), window luminance, and ceiling luminance uniformity were used to assess performance. The performance of both systems was found to have significant seasonal variation, where performance under clear sky conditions improved as maximum solar altitude angles transitioned from solstice to equinox. Although the OLS produced fewer hours per day of DA on average than the Venetian blind, the OLS never exceeded the designated 2000 cd/m2 threshold for window glare. In contrast, the Venetian blind was found to exceed the visual discomfort threshold over a large fraction of the day during equinox conditions. Notably, these peak periods of visual discomfort occurred during the best periods of daylighting performance. Luminance uniformity was analyzed using calibrated high dynamic range luminance images. Under clear sky conditions, the OLS was found to increase the luminance of the ceiling as well as produce a more uniform distribution. Furthermore, compared to conventional venetian blinds, the static optical sunlight redirecting system studied has the potential to significantly reduce the annual electrical lighting energy demand of a daylit space and improve the quality from the perspective of building occupants by consistently transmitting useful daylight while eliminating window glare.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2023

On the convergence of statistics in simulations of stationary incompressible turbulent flows

When reporting statistics from simulations of statistically stationary chaotic phenomenon, it is important to verify that the simulations are time-converged. This condition is connected with the statistical error or number of digits with which statistics can be reliably reported. In this work we consider numerical experiments of low Reynolds number incompressible homogeneous and isotropic turbulence as a model problem to investigate statistical convergence over finite simulation times. Specifically, we investigate the time integration requirements that allow meaningful reporting of the statistical error associated with finiteness of the temporal domain. We address two key questions: (1) How long should a simulation be performed in terms of large eddy time, and (2) How should the simulation time be divided among temporal windows over which a quantity of interest is estimated so that its statistical error could be reliably reported? We find that reliable reporting of statistical errors requires simulations on the order of 10 4 large eddy times, which is orders of magnitude longer than typically performed. Additionally, data post-processing should employ windows of at least ten times the large eddy time scale, with the most robust computation of statistical error of the mean requiring window sizes of an additional factor of ten. For practical simulations, we demonstrate that it is possible to estimate the statistical error within a factor of two under a less stringent condition in which a minimum of four windows with size at least ten large eddy times are used. In conclusion, our observations for homogeneous isotropic turbulence are also shown to hold in turbulent channel flow.

42 ENGINEERING↗

DOE OSTI2013

Global warming implications of facade parameters: A life cycle assessment of residential buildings in Bahrain

On a global scale, the Gulf Corporation Council Countries (GCCC), including Bahrain, are amongst the top countries in terms of carbon dioxide emissions per capita. Building authority in Bahrain has set a target of 40% reduction of electricity consumption and associated CO{sub 2} emissions to be achieved by using facade parameters. This work evaluates how the life cycle CO{sub 2} emissions of buildings are affected by facade parameters. The main focus is placed on direct and indirect CO{sub 2} emissions from three contributors, namely, chemical reactions during production processes (Pco{sub 2}), embodied energy (Eco{sub 2}) and operational energy (OPco{sub 2}). By means of the life cycle assessment (LCA) methodology, it has been possible to show that the greatest environmental impact occurs during the operational phase (80-90%). However, embodied CO{sub 2} emissions are an important factor that needs to be brought into the systems used for appraisal of projects, and hence into the design decisions made in developing projects. The assessment shows that masonry blocks are responsible for 70-90% of the total CO{sub 2} emissions of facade construction, mainly due to their physical characteristics. The highest Pco{sub 2} emissions factors are those of window elements, particularly aluminium frames. However, their contribution of CO{sub 2} emissions depends largely on the number and size of windows. Each square metre of glazing is able to increase the total CO{sub 2} emissions by almost 30% when compared with the same areas of opaque walls. The use of autoclaved aerated concrete (AAC) walls reduces the total life cycle CO{sub 2} emissions by almost 5.2% when compared with ordinary walls, while the use of thermal insulation with concrete wall reduces CO{sub 2} emissions by 1.2%. The outcome of this work offers to the building industry a reliable indicator of the environmental impact of residential facade parameters. - Highlights: Black-Right-Pointing-Pointer Life cycle carbon assessment of facade parameters. Black-Right-Pointing-Pointer Greatest environmental impact occurs during the operational phase. Black-Right-Pointing-Pointer Masonry blocks are responsible for 70-90% of the total CO2 emissions of facade construction. Black-Right-Pointing-Pointer Window contribution of CO2 emissions depends on the number and size of windows. Black-Right-Pointing-Pointer Without insulation, AAC walls offer more savings in CO2 emissions.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2018

Ambient air pollution and pregnancy outcomes: A comprehensive review and identification of environmental public health challenges

There is a growing number of studies on the association between ambient air pollution and adverse pregnancy outcomes, but their results have been inconsistent. Consequently, a comprehensive review of this research area is needed. There was a wide variability in studied pregnancy outcomes, observed gestational windows of exposure, observed ambient air pollutants, applied exposure assessment methods and statistical analysis methods Gestational duration, preterm birth, (low) birth weight, and small for gestational age/intrauterine growth restriction were most commonly investigated pregnancy outcomes. Gestational windows of exposure typically included were whole pregnancy period, 1st, 2nd, 3rd trimester, first and last gestational months. Preterm birth was the outcome most extensively studied across various gestational windows, especially at the beginning and at the end of pregnancy. Particulate matter, nitrogen dioxide, ozone, and carbon monoxide were the most commonly used markers of ambient air pollution. Continuous monitoring data were frequently combined with spatially more precisely modelled estimates of exposure. Exposure to particulate matter and ozone over the entire pregnancy was significantly associated with higher risk for preterm birth: the pooled effect estimates were 1.09 (1.03–1.16) per 10 μg/m{sup 3} increase in particulate matter with an aerodynamic diameter of 10 µm or less (PM{sub 10}){sub ,}1.24 (1.08–1.41) per 10 μg/m{sup 3} increase in particulate matter with an aerodynamic diameter of 2.5 µm or less (PM{sub 2.5}), and 1.03 (1.01–1.04) per 10 ppb increase in ozone. For pregnancy outcomes other than PTB, ranges of observed effect estimates were reported due to smaller number of studies included in each gestational window of exposure. Further research is needed to link the routine pregnancy outcome data with spatially and temporally resolved ambient air pollution data, while adjusting for commonly defined confounders. Methods for assessing exposure to mixtures of pollutants, indoor air pollution exposure, and various other environmental exposures, need to be developed.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2022

Precise ROCOF estimation algorithm for low inertia power grids

The precise estimation of Rate Of Change Of Frequencies (ROCOFs) in a generation trip event can be helpful on power system inertia estimation, fast system response, and accurate event capturing. However, the ROCOF estimations from the existing Synchronized Measurement Devices (SMDs) are usually simply calculated by the finite difference between two adjacent frequency measurement points. The ineluctable noises, disturbances, and spikes from real-world frequency measurements can bring large dynamics to the ROCOF estimation and thus can result in an inaccurate estimation of the initial ROCOF. This issue becomes more serious when the target power grid has low inertia, and a large amount of distributed energy sources are deployed. To address this issue, a precise ROCOF estimation algorithm is designed based on least square method with flexible window size. In addition, a median filter is also designed and applied on the frequency measurements before using the proposed algorithm. The window size and thresholds in the proposed algorithm are determined with historical event data analysis. The proposed algorithm is deployed in a low cost, flexible, and distribution level universal grid analyzer (UGA) platform. In conclusion, multiple experiments are conducted in both a laboratory and the Hawaiian Islands to verify the effectiveness of the proposed algorithm.

24 POWER TRANSMISSION AND DISTRIBUTION↗

DOE OSTI2012

Effect of Recombinant Human Endostatin on Radiosensitivity in Patients With Non-Small-Cell Lung Cancer

Purpose: To observe the effects of recombinant human endostatin (RHES) on the radiosensitivity of non-small cell lung cancer (NSCLC). Methods and Materials: First, 10 hypoxia-positive cases of pathology-diagnosed NSCLC selected from 15 patients were used to determine the normalization window, a period during which RHES improves NSCLC hypoxia. Second, 50 hypoxia-positive cases of pathology-diagnosed NSCLC (Stages I-III) were randomly divided into a RHES plus radiotherapy group (25 cases) and a radiotherapy-alone group (25 cases). Intensity = modulated radiotherapy with a total dose of 60 Gy in 30 fractions for 6 weeks was adopted in the two groups. The target area included primary foci and metastatic lymph nodes. In the RHES plus radiotherapy group, RHES (15 mg/day) was intravenously given during the normalization window. Results: After RHES administration, the tumor-to=normal tissue radioactivity ratio and capillary permeability surface were first decreased and then increased, with their lowest points on the fifth day compared with the first day (all p < 0.01). Blood flow was first increased and then decreased, with the highest point on the fifth day, compared with the first and tenth day (all p < 0.01). In the RHES plus radiotherapy group and the radiotherapy-alone group, the total effective rates (complete response plus partial response) were 80% and 44% (p = 0.009), respectively. The median survival times were 21.1 {+-} 0.97 months and 16.5 {+-} 0.95 months (p = 0.004), respectively. The 1-year and 2-year local control rates were 78.9 {+-} 8.4% and 68.1 {+-} 7.8% (p = 0.027) and 63.6 {+-} 7.2% and 43.4 {+-} 5.7% (p = 0.022), respectively. The 1-year and 2-year overall survival rates were 83.3 {+-} 7.2% and 76.6 {+-} 9.3% (p = 0.247) and 46.3 {+-} 2.4% and 37.6 {+-} 9.1% (p = 0.218), respectively. Conclusion: The RHES normalization window is within about 1 week after administration. RHES combined with radiotherapy within the normalization window has better short-term therapeutic effects and local control rates and no severe adverse reactions in the treatment of NSCLC, but it failed to significantly improve the 1-year and 3-year overall survival rates.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2023

Development and experimental verification of an active noise cancellation (ANC) method for non-invasive sensing

Ultrasonic wave propagation may be used in non-invasive sensing to identify the properties of a fluid in a container. An ultrasonic excitation can be coupled into the liquid or the gas through the walls of the container and detected by a receiver on the other side. However, in addition to this fluid path, another signal will also propagate through the structure and is referred as noise in this study. For most materials, this structural noise will be of higher amplitude compared to the fluid signal due to the large acoustic impedance difference between the solid container and the fluid. In this paper, an active noise cancellation (ANC) method is developed and demonstrated on an experimental setup. It was shown that this method cancels more than 90% of the noise signal in a given time window of interest. A sequential version of this cancellation method is also proposed, and it was shown that its performance improves as the number of canceling excitations is increased. The performance was found to be independent of the location of canceling transducers and position of the silence window but dependent on the width of the silence window. As an example, the ANC method was applied to noise cancellation of a signal travelling through water in a stainless-steel container. The signal-to-noise ratio (SNR) of the water signal in the window of interest was increased by 148% from 13.98 dB to 34.68 dB by using the proposed ANC method.

42 ENGINEERING↗

DOE OSTI2019

Exploiting the Dynamic Relationship between Peptide Separation Quality and Peptide Coisolation in a Multiple-Peptide Matches-per-Spectrum Approach Offers a Strategy To Optimize Bottom-Up Proteomics Throughput and Depth

We present that peptide cofragmentation leads to chimeric MS/MS spectra that negatively impact traditional single-peptide match-per-spectrum (sPSM) search strategies in proteomics. The collection of chimeric spectra is influenced by peptide coelution and the width of precursor isolation windows. Although peptide cofragmentation can be reduced by advanced chromatography, such as UHPLC and 2D-HPLC separation schemes, and narrower isolation windows, chimeric spectra can still be as high as 30–50% of the total MS/MS spectra collected. Alternatively, cofragmented peptides in chimeric spectra and the use of wider isolation windows benefit multiple-peptide matches-per-spectrum (mPSM) algorithms, such as CharmeRT, which facilitate the identification of several cofragmented peptides. Considering recent advancements in LC and mPSM methodologies, we present a comprehensive examination of the levels of chimeric spectra collected in the analysis of a HeLa digest measured using different LC modes of separation and isolation windows and compare the depth of identifications obtained when these data are annotated using a sPSM or a mPSM approach. Our results demonstrate that MS/MS data derived from 1D-HPLC strategies under different gradient schemes and searched with CharmeRT yielded higher average numbers of PSMs (11%–49%), peptide analytes (10%–16%), and peptide sequences (3%–10%) compared to data derived from 1D-UHPLC runs but searched with a sPSM strategy. Interestingly, data from a 2D-HPLC separation strategy benefits more from the application of CharmeRT results when compared to a 50 cm 1D-UHPLC column employing a 500 min gradient. In conclusion, these results provide new insights into how to better configure LC-MS/MS measurements for improved throughput and peptide identification in complex proteomes.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2017

Synthesis and Study of the First Zeolitic Uranium Borate

A complex, three-dimensional, open-framework, lead uranyl borate, (H 2 O)Pb 3 (UO 2 ) 3 B 14 O 27 , denoted as LUBO, was synthesized via a hydrothermal method. LUBO crystallizes in the hexagonal space group P6 3 /m and exhibits a zeolite-like anionic borate framework (B 14 O 27 ) 12- . Additionally, the main structural unit of the framework is a tubule consisting of six-membered B 6 O 18 rings. Each ring is connected to the successive one by three diborate groups, and these tubules propagate along the c axis. The tubules possess six-membered ring (MR) windows in the axial direction and 8-MR windows on its sides. Interconnection of the parallel tubules, which consist exclusively of BO 4 tetrahedra, is provided by triangular BO 3 fragments perpendicular to the axis of the tubules. The framework has large pores as well as channels with 8-MR windows extending along the [100], [010], and [110] directions that are consistent with the overall hexagonal symmetry of the structure. The lead cations occupy 8-MR windows and form [Pb 3 (H 2 O)] groups with attached water molecules that are located at the center of the tubules. The method of Voronoi–Dirichlet tessellation reveals that the lone pairs of the lead cations are located outside the tubule. Uranyl cations form UO 8 coordination polyhedra in the shape of a hexagonal bipyramid. Lastly, the thermal stability and vibrational spectroscopy of LUBO are also delineated in this work.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗