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Rate Coefficient Measurements and Theoretical Analysis of the OH + (E)‑CF₃CH==CHCF₃ Reaction

Description: Rate coefficients, k, for the gas-phase reaction of the OH radical with (E)CF3CHCHCF3 ((E)-1,1,1,4,4,4-hexafluoro-2-butene, HFO-1336mzz(E)) were measured over a range of temperatures (211−374 K) and bath gas pressures (20−300 Torr; He, N2) using a pulsed laser photolysis−laser-induced fluorescence (PLP−LIF) technique. k1(T) was independent of pressure over this range of conditions with k1(296 K) = (1.31 ± 0.15) × 10−13 cm3 molecule−1 s−1 and k1(T) = (6.94 ± 0.80) × 10−13exp[−(496 ± 10)/T] cm 3 molecule−1 s−1, where the uncertainties are 2σ, and the pre-exponential term includes estimated systematic error. Rate coefficients for the OD reaction were also determined over a range of temperatures (262−374 K) at 100 Torr (He). The OD rate coefficients were ∼15% greater than the OH values and showed similar temperature dependent behavior with k2(T) = (7.52 ± 0.44) × 10−13exp[−(476 ± 20)/T] and k2(296 K) = (1.53 ± 0.15) × 10−13 cm3 molecule−1 s−1. The rate coefficients for reaction 1 were also measured using a relative rate technique between 296 and 375 K with k1(296 K) measured to be (1.22 ± 0.1) × 10−13 cm3 molecule−1 s−1, in agreement with the PLP−LIF results. In addition, the 296 K rate coefficient for the O3 +( E)CF3CHCHCF3 reaction was determined to be <5.2 × 10−22 cm3 molecule−1 s−1. A theoretical computational analysis is presented to interpret the observed positive temperature dependence for the addition reaction and the significant decrease in OH reactivity compared to the (Z)-CF3CHCHCF3 stereoisomer reaction. The estimated atmospheric lifetime of (E)-CF3CH CHCF3, due to loss by reaction with OH, is estimated to be ∼90 days, while the actual lifetime will depend on the location and season of its emission. Infrared absorption spectra of (E)-CF3CHCHCF3 were measured and used to estimate the 100 year time horizon global warming potentials (GWP) of 32 (atmospherically well-mixed) and 14 ...
Date: March 22, 2018
Creator: Baasandorj, Munkhbayar; Marshall, Paul; Waterland, Robert L.; Ravishankara, A. R. & Burkholder, James B. (James Bart), 1954-
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Partner: UNT College of Arts and Sciences

Experimental and Computational Studies of the Kinetics of the Reaction of Hydrogen Atoms with Carbon Disulfide

Description: Article discussing an investigation of the reaction of H + CS₂ products. The reaction was found to be pressure dependent and in the fall-off region or near the low pressure limit. Transition state theory yields an estimate for the high-pressure limit of addition over 290–300 K of 1.3 × 10−9 exp( −7.2 kJ mol −1 /RT) cm3 molecule −1 s −1. Uncertainties are discussed in the text.
Date: July 7, 2018
Creator: Kerr, Katherine E.; Gao, Yide & Marshall, Paul
Item Type: Refine your search to only Article
Partner: UNT College of Arts and Sciences

The C₂H₂ + NO₂ Reaction: Implications for High Pressure Oxidation of C₂H₂/NOx Mixtures

Description: Article discussing an experimental and kinetic modeling study of the interaction between C₂H₂ and NOx under flow reactor conditions in the intermediate temperature range (600–900 K), high pressure (50–60 bar), and for stoichiometries ranging from reducing to strongly oxidizing. The results show that presence of NOx serves both to sensitize and inhibit oxidation of C₂H₂.
Date: July 25, 2018
Creator: Marshall, Paul; Leung, Caroline; Gimenez-Lopez, Jorge; Rasmussen, Christian T.; Hashemi, Hamid; Glarborg, Peter et al.
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Partner: UNT College of Arts and Sciences

Further Analysis on Solubility Measurement and Thermodynamic Modeling of Benzoic Acid in Monosolvents and Binary Mixtures

Description: Article discussing further analyses of the recent report (by Sandeepa et al.) on the solubility of benzoic acid in six monosolvents (i.e. tributyl phosphate, diacetone alcohol, methyl-n-propyl ketone, methyl acetate, amyl acetate, and isooctane) and five binary systems (i.e. ethanol + hexane, isopropyl alcohol + hexane and chloroform + hexane, acetone + hexane, and acetone + water) along with some numerical analyses. The reported calculations have been reanalyzed based on combined nearly ideal binary solvent/Redlich-Kister, the modified Wilson model, general single model, Jouyban–Acree model and Jouyban–Acree–van’t Hoff model. The investigated models provide good estimation of the solubility behavior of benzoic acid in the binary solvent mixtures at various temperatures.
Date: June 30, 2019
Creator: Jouyban, Abolghasem; Rahimpour, Elaheh & Acree, William E. (William Eugene)
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Partner: UNT College of Arts and Sciences

The First Stalin Mass Operation (1927)

Description: This article based on new archival documents introduces a new episode of mass operations, which took place in June and July of 1927 and was directed against the broad group of “anti-Soviet” forces. It preceded many practices of mass terror of the 1930s with judicial and extra-legal mechanisms. The goal of this article is to explain motivations, justifications, and mechanisms of this repressive campaign and to put this episode in the wider context of Soviet terror. Facing the combination of a perceived danger of war and real internal social hostility expressed in broad defeatism, both threatening the perpetuation of their governmental powers, authorities resorted to repressions. The 1927 episode highlights the factor of a perceived threat of war as a crucial motivating element in Soviet repressive tactics.
Date: January 2013
Creator: Velikanova, Olga V.
Item Type: Refine your search to only Article
Partner: UNT College of Arts and Sciences

Technical Memorandum: Lewisville Lake Watershed Protection and Management Strategies

Description: With a current population of just over half a million and a 2030 projected population of approximately one million, expansion throughout Denton County shows no sign of slowing down (NCTCOG). Increasingly, freshwater resources are also facing increased pressure from this urban expansion. Effective assessment and management techniques are necessary to protect the diversity of ecosystem services found within fluvial ecosystems and to mitigate current and future conditions of environmental stressor amplified by urban development. The use of various spatial analysis techniques in environmental assessment present more expedient, cost effective, and broader ranging methods of evaluation than traditional field techniques. One such novel evaluation technique is the Water Quality Corridor Management (WQCM) model, developed by the University of North Texas in cooperation with the Upper Trinity Regional Water District (UTRWD). The WQCM model is a geospatial database that utilizes GIS and remote sensing techniques to assess and prioritize stream reaches according to their overall health and sustainability. This project assessed the viability of the WQCM model in reviewing the status of stream systems, and ultimately, established an accurate mechanism for evaluating the stream corridor and surface water quality draining into Lewisville Lake, a popular recreation site and drinking water source for the urbanizing Dallas and Fort Worth metropolitan area.
Date: September 2007
Creator: Atkinson, Samuel F.; Hunter, Bruce Allan; English, April; Boe, Brian & Dameron, Matt
Item Type: Refine your search to only Text
Partner: UNT College of Arts and Sciences

Some numerical analyses on the solubility of vanillin in Carbitol® + water solvent mixtures

Description: This article reports solubility values of vanillin (component 3) in 2-(2-ethoxyethoxy)ethanol (Carbitol®, component 1) + water (component 2) mixtures at five temperatures from 298.15 to 318.15 K correlated with the Jouyban-Acree model combined with van't Hoff or Apelblat equations, and obtains models in second degree regarding the mixtures compositions.
Date: May 25, 2015
Creator: Martínez, Fleming; Jouyban, Abolghasem & Acree, William E. (William Eugene)
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Partner: UNT College of Arts and Sciences

Combining semi-synthesis with plant and microbial biocatalysis: new frontiers in producing a chemical arsenal against cancer

Description: This article demonstrates the methods of semi-synthesis and biocatalysis that can be used as modules in succession and in different combinations to produce 6,8-dibromogenkwanin, a derivative of the anticancer natural product apigenin.
Date: June 4, 2018
Creator: Gary, Samuel; Adegboye, Janet; Popp, Brian; Cocuron, Jean-Christophe; Woodrum, Brooklyn & Kovinich, Nik
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Partner: UNT College of Arts and Sciences

Rapid Responses to Abiotic Stress: Priming the Landscape for the Signal Transduction Network

Description: This article proposes that the integration of these signals is mediated through pulses of gene expression that are coordinated through out the plant in a systemic manner by the ROS/Ca⁺² waves.
Date: November 3, 2018
Creator: Kollist, Hannes; Zandalinas, Sara I.; Sengupta, Soham; Nuhkat, Maris; Kangasjärvi, Jaakko & Mittler, Ron
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Partner: UNT College of Arts and Sciences

Data on whole length myosin binding protein C stabilizes myosin S2 as measured by gravitational force spectroscopy

Description: This article relates to the research article entitled "Whole length myosin binding protein C stabilized myosin subfragment-2 (s2) flexibility as measured by gravitational force spectroscopy" (Singh et al., 2018) [1]. The data exhibited the purified skeletal myosin binding protein (MyBPC) from rabbit back muscle was of slow skeletal type confirmed by chromatography and in unphosphorylated state based on its isoelectric point (pI) by chromatofocussing.
Date: December 4, 2017
Creator: Singh, Rohit R.; Dunn, James W.; Qadan, Motamed M.; Hall, Nakiuda; Wang, Kathy K. & Root, Douglas D.
Item Type: Refine your search to only Article
Partner: UNT College of Arts and Sciences

Gene regulatory networks for lignin biosynthesis in switchgrass (Panicum virgatum)

Description: This article presents a combination of computational and experimental approaches to develop gene regulatory networks for lignin formation in switchgrass (Panicum virgatum), which has been selected as a biofuel crop in the United States.
Date: May 11, 2018
Creator: Rao, Xiaolan; Chen, Xin; Shen, Hui; Ma, Qin; Li, Guifen; Tang, Yuhong et al.
Item Type: Refine your search to only Article
Partner: UNT College of Arts and Sciences

Facile Photochemical Syntheses of Conjoined Nanotwin Gold-Silver Particles within a Biologically-Benign Chitosan Polymer

Description: This article developed a simple photochemical method for making conjoined bi-metallic gold-silver (Au/Ag) nanotwins, a new breed of nanoparticles.
Date: March 6, 2019
Creator: Korir, Daniel K.; Gwalani, Bharat; Joseph, Abel; Kamras, Brian; Arvapally, Ravi K.; Omary, Mohammad A. et al.
Item Type: Refine your search to only Article
Partner: UNT College of Arts and Sciences

Giant spin Hall effect in two-dimensional monochalcogenides

Description: This article, using calculations from first principles, reveals for the first time giant intrinsic spin Hall conductivities (SHC) in these materials. In particular, the article shows that the SHC resonances can be easily tuned by combination of strain and doping and, in some cases, strain can be used to induce semiconductor to metal transition that makes a giant spin Hall effect possible even in absence of doping.
Date: October 30, 2018
Creator: Sławińska, Jagoda; Cerasoli, Frank T.; Wang, Haihang; Postorino, Sara; Supka, Andrew; Curtarolo, Stefano et al.
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Partner: UNT College of Arts and Sciences

America Losing its Religion?

Description: Audio recording of a news segment from News Radio KFB. This episode discusses results from the General Social Survey in relation to religion and spirituality.
Date: April 9, 2019
Creator: Mendonsa, Cristina & Jain, Pankaj
Item Type: Refine your search to only Sound
Partner: UNT College of Arts and Sciences

Episode 13: Dr. Pankaj Jain

Description: Interview with Dr. Pankaj Jain for the Osher Lifelong Learning Institute (OLLI) podcast. In this episode, Susan speaks with Dr. Pankaj Jain, Associate Professor in UNT's Department of Philosophy & Religion. They discuss Dr. Jain's interest in connecting ancient practices with contemporary issues, and how he is exploring the connections between religious traditions and sustainability in the US and in India. They also discuss his recent trip to Nepal, where he recorded an episode of National Geographic Channel's "The Story of God" with Morgan Freeman. The episode will air on April 9, 2019.
Date: March 7, 2019
Creator: Supak, Susan & Jain, Pankaj
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Partner: UNT College of Arts and Sciences

Episode 1: Dr. Craig Neumann

Description: Interview with Dr. Craig Neumann for the Osher Lifelong Learning Institute (OLLI) podcast. In this episode, Susan interviews Dr. Craig Neumann, Distinguished Research Professor in UNT's Department of Psychology, about his background and his research on subjects like psychopathy and mindfulness.
Date: December 12, 2018
Creator: Supak, Susan & Neumann, Craig S.
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Partner: UNT College of Arts and Sciences

Episode 4: Dr. Reid Ferring

Description: Interview with Dr. Reid Ferring for the Osher Lifelong Learning Institute (OLLI) podcast. In this episode, Susan has a wide-ranging conversation with Dr. Reid Ferring of UNT's Department of Geography and the Environment. They discuss his professional accomplishments in the fields of archaeology and geology, why he loves teaching for OLLI, and the reasons for his interest in the relationship between science and faith.
Date: January 2, 2019
Creator: Supak, Susan & Ferring, C. Reid
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Partner: UNT College of Arts and Sciences

Episode 6: Dr. Andrew Torget

Description: Interview with Dr. Andrew Torget for the Osher Lifelong Learning Institute (OLLI) podcast. In this episode, Susan has a wide-ranging discussion with Andrew Torget, Associate Professor in UNT's History Department. She and Dr. Torget discuss why it's important for us to learn about history, how he recently made history by teaching the world's longest history lesson, and his connection to the recent discovery of a safe full of documents that reveal the presumed-lost history of the Galveston City Company.
Date: January 16, 2019
Creator: Supak, Susan & Torget, Andrew J.
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Partner: UNT College of Arts and Sciences

Episode 11: Dr. James Goodnow Pt. 2 (Day Trippers)

Description: Interview with Dr. James Goodnow for the Osher Lifelong Learning Institute (OLLI) podcast. Susan speaks with him about his work as co-chair of the Day Trippers Special Interest Group. Dr. Goodnow explains the background of this OLLI at UNT group and the types of trips they'll be taking this semester.
Date: February 21, 2019
Creator: Supak, Susan & Goodnow, James D.
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Partner: UNT College of Arts and Sciences

Episode 10: Dr. James Goodnow Pt. 1 (Great Decisions)

Description: Interview with Dr. James Goodnow for the Osher Lifelong Learning Institute (OLLI) podcast. In this episode, Susan sits down with Dr. James Goodnow, Adjunct Professor of International Studies at UNT, to discuss a special series of discussions he's offering for OLLI at UNT this semester as part of the nationwide Great Decisions global affairs program. Dr. Goodnow explains how these discussions work and also talks with Susan about his academic background, how he became involved with OLLI at UNT, and his personal experiences traveling around the world.
Date: February 15, 2019
Creator: Supak, Susan & Goodnow, James D.
Item Type: Refine your search to only Sound
Partner: UNT College of Arts and Sciences