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Data From: Computational Prediction Of The Low-Temperature Ferromagnetic Semiconducting 2d Sin Monolayer, Alexander I. Boldyrev, Nikolay Tkachenko 2021 Utah State University

Data From: Computational Prediction Of The Low-Temperature Ferromagnetic Semiconducting 2d Sin Monolayer, Alexander I. Boldyrev, Nikolay Tkachenko

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Since the discovery of graphene, 2D materials have captured the minds of scientists because of their attractive and unique electronic properties. In particular, magnetic 2D materials have become a subject of extensive discussions today. Using density functional theory calculations, it is shown that 2D SiN sheet (built out of nonmetallic main group atoms) is a ferromagnetic semiconducting material with a magnetic moment 1 μB per unit cell and an indirect bandgap of 1.55 eV. Calculated phonon spectrum and conducted ab initio molecular dynamics simulation reveal thermal and dynamical stability of the designed material. It is shown that the ferromagnetic ...


Lessons From A Landscape Irrigation Rebate Program In Miami Dade County, Haimanote K. Bayabil, Laura Vasquez, Jesus Lomeli, Patrick Martin 2021 University of Florida

Lessons From A Landscape Irrigation Rebate Program In Miami Dade County, Haimanote K. Bayabil, Laura Vasquez, Jesus Lomeli, Patrick Martin

Journal of Extension

We calculated savings in outdoor water uses from 37 properties in Fisher Island, Florida, that were retrofitted with smart Evapotranspiration-based irrigation controllers through the Miami Dade County’s Landscape Irrigation Rebate Program. We found average water savings of 11.4 million gallons per year from the 37 properties on the island. We discuss the roles of extension personnel in developing and effectively managing an irrigation rebate program and the implications of results from this program for large scale efforts towards efficient use of freshwater resources.


Data From: Dibridged, Monobridged, Vinylidene-Like, And Linear Structures For The Alkaline Earth Dihydrides Be2h2, Mg2h2, Ca2h2, Sr2h2, And Ba2h2. Proposals For Observations, Alexander I. Boldyrev, Nikolay Tkachenko 2021 Utah State University

Data From: Dibridged, Monobridged, Vinylidene-Like, And Linear Structures For The Alkaline Earth Dihydrides Be2h2, Mg2h2, Ca2h2, Sr2h2, And Ba2h2. Proposals For Observations, Alexander I. Boldyrev, Nikolay Tkachenko

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This research reports a search for peculiar monobridged structures of the E2H2 molecules (E = Be, Mg, Ca, Sr, Ba). For Be2H2 and Mg2H2, the monobridged geometry is not an equilibrium but rather a transition state between the vinylidene-like structure and the global minimum HE–EH linear geometry. However, for Ca2H2, Sr2H2, and Ba2H2, this situation changes significantly; the linear structure is no longer the global minimum but lies higher in energy than two other equilibria, the dibridged and monobridged structures. The planar dibridged structures of both Sr2H2 and Ba2H2 should be observable via IR spectroscopy. Although the remarkable monobridged structures ...


Data For: Record Low Ionization Potentials Of Alkali Metal Complexes With Crown Ethers And Cryptands, Alexander I. Boldyrev, Nikolay Tkachenko 2021 Utah State University

Data For: Record Low Ionization Potentials Of Alkali Metal Complexes With Crown Ethers And Cryptands, Alexander I. Boldyrev, Nikolay Tkachenko

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Electronic properties of series of alkali metals complexes with crown ethers and cryptands were studied via DFT hybrid functionals. For [M([2.2.2]crypt)] (M=Li, Na, K) extremely low (1.70–1.52 eV) adiabatic ionization potentials were found. Such low values of ionization energies are significantly lower than those of alkali metal atoms. Thus, the investigated complexes can be defined as superalkalis. As a result, our investigation opens up new directions in the designing of chemical species with record low ionization potentials and extends the explanation of the ability of the cryptates and alkali crown ether complexes ...


Dataset For: Multiple Local Σ-Aromaticity Of Nonagermanide Clusters, Alexander I. Boldyrev, Nikolay Tkachenko 2021 Utah State University

Dataset For: Multiple Local Σ-Aromaticity Of Nonagermanide Clusters, Alexander I. Boldyrev, Nikolay Tkachenko

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Nonagermanide clusters are widely used in inorganic synthesis and are actively studied by experimentalists and theoreticians. However, chemical bonding of such versatile species is still not completely understood. In our work we deciphered a bonding pattern for various experimentally obtained nonagermanide species. We localized the electron density via the AdNDP algorithm for the model structures ([Ge9]4−, [Ge9{P(NH2)2}3]−, Cu[Ge9{P(NH2)2}3] and Cu(NHC)[Ge9{P(NH2)2}3]) and obtained a simple and chemically intuitive bonding pattern which can explain the variety of active sites and the existence of both D3h and ...


Literature Review: Pollutant Removal Efficacy Of Floating Treatment Wetlands Across Water Bodies, Sophie Johnson 2021 Portland State University

Literature Review: Pollutant Removal Efficacy Of Floating Treatment Wetlands Across Water Bodies, Sophie Johnson

University Honors Theses

Wetland numbers are declining worldwide and there is a need to replace the water filtration services they provide. One emerging option is floating treatment wetlands (FTW). FTW are a floating mat that serves as a habitat for aquatic plants whose roots are suspended in the water and that remove both organic and inorganic pollutants like nutrients (nitrogen and phosphorus), potentially toxic metals, and suspended solids. A literature search was performed to examine the efficacy of FTW pollutant removal. Specifically, I inspected 1) how effective FTW are at removing a range of nutrients; 2) what types of plants are most effective ...


Do Secondary Cyclones Increase The Category Scale Of Atmospheric Rivers?, Edgar Sanchez Fausto 2021 Portland State University

Do Secondary Cyclones Increase The Category Scale Of Atmospheric Rivers?, Edgar Sanchez Fausto

University Honors Theses

Atmospheric rivers (ARs) play a crucial role in delivering precipitation worldwide. This makes them an important phenomenon for water resource specialists to study. One such interest is to understand what mechanisms make ARs produce significant rainfall and associated hazards such as flooding. One possible mechanism is that AR duration or intensity may increase when it interacts with a secondary cyclone, either of which can increase the AR category scale. The purpose of this study is to determine whether AR and secondary cyclone interactions increase the category scale ARs. Out of 52 AR events analyzed, 32 events contained at least one ...


Self-Contained Photon Coincidence Counting With National Instruments Myrio Ecosystem, Georges Mason Edouard Oates Larsen, Andres H. La Rosa 2021 Portland State University

Self-Contained Photon Coincidence Counting With National Instruments Myrio Ecosystem, Georges Mason Edouard Oates Larsen, Andres H. La Rosa

University Honors Theses

Digital coincidence counting units (CCU) have made experimental verification of fundamental quantum mechanical principles financially accessible to undergraduate level teaching programs. However, recent implementations of these systems are not easily ported to National Instruments (NI) FPGAs, making them unsuitable for physics departments that have heavily invested in the NI ecosystem. Therefore, there is clear need for a detailed implementation based on an NI FPGA. We present a formal description of one such implementation, based on the NI myRIO (NI's lower-cost, student-oriented offering) which achieves 6.9 ns minimum guaranteed-distinguishable delay and 32.2 MHz peak coincidence counting rate with ...


St-V-Net: Incorporating Shape Prior Into Convolutional Neural Netwoks For Proximal Femur Segmentation, Chen Zhao, Joyce H. Keyak, Jinshan Tang, Tadashi S. Kaneko, Sundeep Khosla, Shreyasee Amin, Elizabeth J. Atkinson, Lan-Juan Zhao, Michael J. Serou, Chaoyang Zhang, Hui Shen, Hong-Wen Deng, Weihua Zhou 2021 Michigan Technological University

St-V-Net: Incorporating Shape Prior Into Convolutional Neural Netwoks For Proximal Femur Segmentation, Chen Zhao, Joyce H. Keyak, Jinshan Tang, Tadashi S. Kaneko, Sundeep Khosla, Shreyasee Amin, Elizabeth J. Atkinson, Lan-Juan Zhao, Michael J. Serou, Chaoyang Zhang, Hui Shen, Hong-Wen Deng, Weihua Zhou

Faculty Publications

We aim to develop a deep-learning-based method for automatic proximal femur segmentation in quantitative computed tomography (QCT) images. We proposed a spatial transformation V-Net (ST-V-Net), which contains a V-Net and a spatial transform network (STN) to extract the proximal femur from QCT images. The STN incorporates a shape prior into the segmentation network as a constraint and guidance for model training, which improves model performance and accelerates model convergence. Meanwhile, a multi-stage training strategy is adopted to fine-tune the weights of the ST-V-Net. We performed experiments using a QCT dataset which included 397 QCT subjects. During the experiments for the ...


Revealing The Surface Structure Of Cdse Nanocrystals By Dynamic Nuclear Polarization-Enhanced 77se And 113cd Solid-State Nmr Spectroscopy, Yunhua Chen, Rick W. Dorn, Michael P. Hanrahan, Lin Wei, Rafael Blome-Fernández, Alan M. Medina-Gonzalez, Marquix A. S. Adamson, Anne H. Flintgruber, Javier Vela, Aaron J. Rossini 2021 Iowa State University and Ames Laboratory

Revealing The Surface Structure Of Cdse Nanocrystals By Dynamic Nuclear Polarization-Enhanced 77se And 113cd Solid-State Nmr Spectroscopy, Yunhua Chen, Rick W. Dorn, Michael P. Hanrahan, Lin Wei, Rafael Blome-Fernández, Alan M. Medina-Gonzalez, Marquix A. S. Adamson, Anne H. Flintgruber, Javier Vela, Aaron J. Rossini

Chemistry Publications

Dynamic nuclear polarization (DNP) solid-state NMR (SSNMR) spectroscopy was used to obtain detailed surface structures of zinc blende CdSe nanocrystals (NCs) with plate or spheroidal morphologies which are capped by carboxylic acid ligands. 1D 113Cd and 77Se cross-polarization magic angle spinning (CPMAS) NMR spectra revealed distinct signals from Cd and Se atoms on the surface of the NCs, and those residing in bulk-like environments, below the surface. 113Cd cross-polarization magic-angle-turning (CP-MAT) experiments identified CdSe3O, CdSe2O2, and CdSeO3 Cd coordination environments on the surface of the NCs, where the oxygen atoms are presumably from coordinated carboxylate ligands. The sensitivity gain from ...


Environmental, Health And Safety Intricacies Of Artisanal Mining In The Gold-Rich Landscapes Of Karamoja, North-Eastern Uganda, Eria Serwajja, Paul Isolo Mukwaya 2021 Makerere University

Environmental, Health And Safety Intricacies Of Artisanal Mining In The Gold-Rich Landscapes Of Karamoja, North-Eastern Uganda, Eria Serwajja, Paul Isolo Mukwaya

Journal of Sustainable Mining

Artisanal small-scale gold mining presents opportunities for Uganda’s rural poor. However, it also poses serious environmental, health and safety challenges. A suite of data collection methods including interviews, focus groups discussions, water and soils sampling were used to examine the perceptions of miners on the status, prevalence and extent of mercury use in artisanal gold mining, mercury transit routes and toxicity levels of soils and water in Karamoja sub-region. It also explores the health, safety and environmental implications of artisanal small-scale gold mining in the sub-region. The findings show that trade and access to mercury is widespread; although trade ...


Studies On Relationship Of Sex Ratio And Population Of Clawed Jird And Striped Hamster, Liqing Wang, Yuping Yang, Xiaodong Wu, Xixian Hou, Weihui Dong 2021 Chinese Academy of Agricultural Sciences, China

Studies On Relationship Of Sex Ratio And Population Of Clawed Jird And Striped Hamster, Liqing Wang, Yuping Yang, Xiaodong Wu, Xixian Hou, Weihui Dong

International Grassland Congress Proceedings

No abstract provided.


Control Of Noxious Weed Cenchrus Biflorus—Effect Of Lablab As A Cover Crop, F. Peter Wandera, A. Abdullahi 2021 Kenya Agricultural Research Institute, Kenya

Control Of Noxious Weed Cenchrus Biflorus—Effect Of Lablab As A Cover Crop, F. Peter Wandera, A. Abdullahi

International Grassland Congress Proceedings

No abstract provided.


Data From: Structure And Bonding In [Sb@In8sb12]3− And [Sb@In8sb12]5−, Alexander I. Boldyrev, Nikolay Tkachenko 2021 Utah State University

Data From: Structure And Bonding In [Sb@In8sb12]3− And [Sb@In8sb12]5−, Alexander I. Boldyrev, Nikolay Tkachenko

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We report the characterization of the compound [K([2.2.2]crypt)]4[In8Sb13], which proves to contain a 1:1 mixture of [Sb@In8Sb12]3− and [Sb@In8Sb12]5−. The tri-anion displays perfect Th symmetry, the first completely inorganic molecule to do so, and contains eight equivalent In3+ centers in a cube. The gas-phase potential energy surface of the penta-anion has eight equivalent minima where the extra pair of electrons is localized on one In+ center, and these minima are linked by low-lying transition states where the electron pair is delocalized over two adjacent centers. The best fit to ...


Data From: All-Metal Σ-Antiaromaticity In Dimeric Cluster Anion {[Cuge9mes]2}4−, Alexander I. Boldyrev, Nikolay Tkachenko 2021 Utah State University

Data From: All-Metal Σ-Antiaromaticity In Dimeric Cluster Anion {[Cuge9mes]2}4−, Alexander I. Boldyrev, Nikolay Tkachenko

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In this work, we report a dimeric cluster anion, {[CuGe9Mes]2}4−, which was isolated as the [K(2,2,2-crypt)]+ salt and characterized by using single-crystal X-ray diffraction and ESI mass spectroscopy. The title cluster represents the first locally σ-antiaromatic compound in the solid state, as well as the first heteroatomic antiaromatic compound.


Data From: Σ-Aromaticity-Induced Stabilization Of Heterometallic Supertetrahedral Clusters [Zn6ge16]4− And [Cd6ge16]4−, Alexander I. Boldyrev, Nikolay Tkachenko 2021 Utah State University

Data From: Σ-Aromaticity-Induced Stabilization Of Heterometallic Supertetrahedral Clusters [Zn6ge16]4− And [Cd6ge16]4−, Alexander I. Boldyrev, Nikolay Tkachenko

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In this work, the largest heterometallic supertetrahedral clusters, [Zn6Ge16]4− and [Cd6Ge16]4−, were directly self-assembled through highly-charged [Ge4]4− units and transition metal cations, in which 3-center–2-electron σ bonding in Ge2Zn or Ge2Cd triangles plays a vital role in the stabilization of the whole structure. The cluster structures have an open framework with a large central cavity of diameter 4.6 Å for Zn and 5.0 Å for Cd, respectively. Time-dependent HRESI-MS spectra show that the larger clusters grow from smaller components with a single [Ge4]4− and ZnMes2 units. Calculations performed at the DFT level indicate ...


On-Chip Nanoscale Plasmonic Optical Modulators, Abdalrahman Mohamed Nader Abdelhamid 2021 American University in Cairo

On-Chip Nanoscale Plasmonic Optical Modulators, Abdalrahman Mohamed Nader Abdelhamid

Theses and Dissertations

In this thesis work, techniques for downsizing Optical modulators to nanoscale for the purpose of utilization in on chip communication and sensing applications are explored. Nanoscale optical interconnects can solve the electronics speed limiting transmission lines, in addition to decrease the electronic chips heat dissipation. A major obstacle in the path of achieving this goal is to build optical modulators, which transforms data from the electrical form to the optical form, in a size comparable to the size of the electronics components, while also having low insertion loss, high extinction ratio and bandwidth. Also, lap-on-chip applications used for fast diagnostics ...


Rare And Critical Metals In Pyrite, Chalcopyrite, Magnetite, And Titanite From The Vathi Porphyry Cu-Au±Mo Deposit, Northern Greece, Christos L. Stergiou, Vasilios Melfos, Panagiotis Voudouris, Lambrini Papadopoulou, Paul G. Spry, Irena Peytcheva, Dimitrina Dimitrova, Elitsa Stefanova, Katerina Giouri 2021 Aristotle University of Thessaloniki

Rare And Critical Metals In Pyrite, Chalcopyrite, Magnetite, And Titanite From The Vathi Porphyry Cu-Au±Mo Deposit, Northern Greece, Christos L. Stergiou, Vasilios Melfos, Panagiotis Voudouris, Lambrini Papadopoulou, Paul G. Spry, Irena Peytcheva, Dimitrina Dimitrova, Elitsa Stefanova, Katerina Giouri

Geological and Atmospheric Sciences Publications

The Vathi porphyry Cu-Au±Mo deposit is located in the Kilkis ore district, northern Greece. Hydrothermally altered and mineralized samples of latite and quartz monzonite are enriched with numerous rare and critical metals. The present study focuses on the bulk geochemistry and the mineral chemistry of pyrite, chalcopyrite, magnetite, and titanite. Pyrite and chalcopyrite are the most abundant ore minerals at Vathi and are related to potassic, propylitic, and sericitic hydrothermal alterations (A- and D-veins), as well as to the late-stage epithermal overprint (E-veins). Magnetite and titanite are found mainly in M-type veins and as disseminations in the potassic-calcic alteration ...


Ancillary Steric Effects On The Activation Of Sih Bonds In Arylsilazido Rare-Earth Compounds, Kasuni C. Boteju, Amrit Venkatesh, Yang-Yun Chu, Suchen Wan, Arkady Ellern, Aaron J. Rossini, Aaron D. Sadow 2021 Iowa State University and Ames Laboratory

Ancillary Steric Effects On The Activation Of Sih Bonds In Arylsilazido Rare-Earth Compounds, Kasuni C. Boteju, Amrit Venkatesh, Yang-Yun Chu, Suchen Wan, Arkady Ellern, Aaron J. Rossini, Aaron D. Sadow

Chemistry Publications

Three new hydridosilazido ligands, −N(SiHMe2)Aryl (Aryl = Ph, 2,6-C6Me2H3 (dmp), 2,6-C6iPr2H3 (dipp)) and their rare-earth complexes Ln{N(SiHMe2)Aryl}3(THF)n (Ln = Sc, Y, Lu; Aryl = Ph, n = 2; Aryl = dmp, n = 1; Aryl = dipp, n = 0) were synthesized to study the relationships among ligand steric properties, secondary Ln↼H–Si bonding, and the reactivity of amide and SiH groups. In these compounds, the steric encumbrance of the aryl group was systematically increased from phenyl to 2,6-dimethylphenyl to 2,6-diisopropylphenyl. NMR, IR, and X-ray diffraction studies of the complexes characterize the number ...


Effect Of Grassland Management On The Occurrence Of The Poisonous Species Senecio Jacobaea, Matthias Suter, John Connolly, Andreas Lüscher 2021 Swiss Grassland Society, Switzerland

Effect Of Grassland Management On The Occurrence Of The Poisonous Species Senecio Jacobaea, Matthias Suter, John Connolly, Andreas Lüscher

International Grassland Congress Proceedings

No abstract provided.


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