Open Access. Powered by Scholars. Published by Universities.®
![Digital Commons Network](http://assets.bepress.com/20200205/img/dcn/DCsunburst.png)
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Institution
-
- University of Nebraska - Lincoln (8)
- Old Dominion University (6)
- Chapman University (5)
- University of Connecticut (5)
- Western Kentucky University (4)
-
- City University of New York (CUNY) (3)
- Florida International University (2)
- The British University in Egypt (2)
- University of Dayton (2)
- University of Texas Rio Grande Valley (2)
- California Polytechnic State University, San Luis Obispo (1)
- Calvin University (1)
- St. Cloud State University (1)
- University of Kentucky (1)
- University of Windsor (1)
- Keyword
-
- Basis sets (2)
- CO oxidation (2)
- Computational chemistry (2)
- Cubic (2)
- Ozone (2)
-
- Ru (2)
- Van der Waals (2)
- 304 Stainless Steel (1)
- 3D (1)
- Ab initio molecular dynamics (1)
- Aerosol (1)
- Aligned molecules (1)
- Aminoacyl-tRNA Synthetases (1)
- Aromatic (1)
- Atoms (1)
- Automobile emission (1)
- Biomass burning (1)
- Blue light (1)
- Bone (1)
- CO desoprtion (1)
- CO desorption (1)
- CPO (1)
- Calcium phosphate (1)
- Carbon dioxide (1)
- Carrier mobility (1)
- Cerium oxide (1)
- Charge transfer (1)
- Chemical calculations (1)
- Chemical elements (1)
- Chemical thermodynamics (1)
- Publication
-
- Xiao Cheng Zeng Publications (6)
- Chemistry & Biochemistry Faculty Publications (5)
- Biology, Chemistry, and Environmental Sciences Faculty Articles and Research (4)
- Chemistry Education Materials (4)
- Masters Theses & Specialist Projects (4)
-
- Chemistry Faculty Publications (3)
- Publications and Research (3)
- Chemical Engineering (2)
- Chemistry Faculty Publications and Presentations (2)
- FIU Electronic Theses and Dissertations (2)
- Chemistry and Biochemistry Publications (1)
- Computational Modeling & Simulation Engineering Faculty Publications (1)
- Department of Chemistry: Dissertations, Theses, and Student Research (1)
- Honors Scholar Theses (1)
- Martin Centurion Publications (1)
- Pharmacy Faculty Articles and Research (1)
- Physics and Astronomy Faculty Publications (1)
- STAR Program Research Presentations (1)
- University Faculty Publications and Creative Works (1)
Articles 31 - 44 of 44
Full-Text Articles in Physical Sciences and Mathematics
Probing The Transition State Region In Catalytic Co Oxidation On Ru, H. Öström, H. Öberg, H. Xin, Jerry L. Larue, M. Beye, M. Dell'angela, J. Gladh, M. L. Ng, J. A. Sellberg, S. Kaya, G. Mercurio, D. Nordlund, M. Hantschmann, F. Hieke, D. Kühn, W. F. Schlotter, G. L. Dakovski, J. J. Turner, M. P. Minitti, A. Mitra, S. P. Moeller, A. Föhlisch, M. Wolf, W. Wurth, M. Persson, J. K. Nørskov, F. Abild-Pedersen, H. Ogasawara, L. G. M. Pettersson, A. Nilsson
Probing The Transition State Region In Catalytic Co Oxidation On Ru, H. Öström, H. Öberg, H. Xin, Jerry L. Larue, M. Beye, M. Dell'angela, J. Gladh, M. L. Ng, J. A. Sellberg, S. Kaya, G. Mercurio, D. Nordlund, M. Hantschmann, F. Hieke, D. Kühn, W. F. Schlotter, G. L. Dakovski, J. J. Turner, M. P. Minitti, A. Mitra, S. P. Moeller, A. Föhlisch, M. Wolf, W. Wurth, M. Persson, J. K. Nørskov, F. Abild-Pedersen, H. Ogasawara, L. G. M. Pettersson, A. Nilsson
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
Femtosecond x-ray laser pulses are used to probe the CO oxidation reaction on Ru initiated by an optical laser pulse. On a timescale of a few hundred femtoseconds, the optical laser pulse excites motions of CO and O on the surface allowing the reactants to collide and, with a transient close to a picosecond (ps), new electronic states appear in the O K-edge x-ray absorption spectrum. Density functional theory calculations indicate that these result from changes in the adsorption site and bond-formation between CO and O with a distribution of OC—O bond lengths close to the transition state (TS). After …
Simultaneous Analysis Of The Ballik-Ramsay And Phillips Systems Of C2 And Observation Of Forbidden Transitions Between Singlet And Triplet States, Wang Chen, Kentarou Kawaguchi, Peter F. Bernath, Jian Tang
Simultaneous Analysis Of The Ballik-Ramsay And Phillips Systems Of C2 And Observation Of Forbidden Transitions Between Singlet And Triplet States, Wang Chen, Kentarou Kawaguchi, Peter F. Bernath, Jian Tang
Chemistry & Biochemistry Faculty Publications
6229 lines of the Ballik-Ramsay system (b3Σg--a3Πu) and the Phillips system (A1Πu-X1Σg+) of C2 up to v = 8 and J = 76, which were taken from the literature or assigned in the present work, were analyzed simultaneously by least-squares fitting with 82 Dunham-like molecular parameters and spin-orbit interaction constants between the b3Σg- and X1Σg+ states with a standard deviation of 0.0037 cm-1 for the whole data set. As a …
Multiple-Time Step Ab Initio Molecular Dynamics Based On Two-Electron Integral Screening, Shervin Fatehi, Ryan P. Steele
Multiple-Time Step Ab Initio Molecular Dynamics Based On Two-Electron Integral Screening, Shervin Fatehi, Ryan P. Steele
Chemistry Faculty Publications and Presentations
A multiple-timestep ab initio molecular dynamics scheme based on varying the two-electron integral screening method used in Hartree–Fock or density functional theory calculations is presented. Although screening is motivated by numerical considerations, it is also related to separations in the length- and timescales characterizing forces in a molecular system: Loose thresholds are sufficient to describe fast motions over short distances, while tight thresholds may be employed for larger length scales and longer times, leading to a practical acceleration of ab initio molecular dynamics simulations. Standard screening approaches can lead, however, to significant discontinuities in (and inconsistencies between) the energy and …
Substrate-Assisted And Enzymatic Pretransfer Editing Of Nonstandard Amino Acids By Methionyl-Trna Synthetase, Grant B. Fortowsky, Daniel J. Simard, Mohamed M. Aboelnga, James W. Gauld
Substrate-Assisted And Enzymatic Pretransfer Editing Of Nonstandard Amino Acids By Methionyl-Trna Synthetase, Grant B. Fortowsky, Daniel J. Simard, Mohamed M. Aboelnga, James W. Gauld
Chemistry and Biochemistry Publications
Aminoacyl-tRNA synthetases (aaRSs) are cen- tral to a number of physiological processes, including protein biosynthesis. In particular, they activate and then transfer their corresponding amino acid to the cognate tRNA. This is achieved with a generally remarkably high fidelity by editing against incorrect standard and nonstandard amino acids. Using docking, molecular dynamics (MD), and hybrid quantum mechanical/molecular mechanics methods, we have inves- tigated mechanisms by which methionyl-tRNA synthetase (MetRS) may edit against the highly toxic, noncognate, amino acids homocysteine (Hcy) and its oxygen analogue, homo- serine (Hse). Substrate-assisted editing of Hcy-AMP in which its own phosphate acts as the mechanistic …
Unraveling The Mechanism Of Selective Ion Transport In Hydrophobic Subnanometer Channels, Hui Li, Joseph S. Francisco, Xiao Cheng Zeng
Unraveling The Mechanism Of Selective Ion Transport In Hydrophobic Subnanometer Channels, Hui Li, Joseph S. Francisco, Xiao Cheng Zeng
Xiao Cheng Zeng Publications
Recently reported synthetic organic nanopore (SONP) can mimic a key feature of natural ion channels, i.e., selective ion transport. However, the physical mechanism underlying the K+/Na+ selectivity for the SONPs is dramatically different from that of natural ion channels. To achieve a better understanding of the selective ion transport in hydrophobic subnanometer channels in general and SONPs in particular, we perform a series of ab initio molecular dynamics simulations to investigate the diffusivity of aqua Na+ and K+ ions in two prototype hydrophobic nanochannels: (i) an SONP with radius of 3.2 Å, and (ii) single-walled …
The Van Der Waals Equation As A Cubic, Carl W. David
The Van Der Waals Equation As A Cubic, Carl W. David
Chemistry Education Materials
The van der Waals (from his thesis of 1873) equation is a cubic in the molar volume. Since this is the first equation of state studied in chemistry more complicated than the ideal gas equation, it is noteworthy that the solution of this cubic is rarely if ever addressed. When (lowering the temperature) the two imaginary roots coalesce with the real root of the van der Waals equation we have the critical point. At Kelvin temperatures below Tc. the equation has three real roots; we explore obtaining those roots to aid in the Maxwell construction required to obtain the vapor …
Electronic Structures And Electronic Spectra Of All-Boron Fullerene B40, Rongxing He, Xiao Cheng Zeng
Electronic Structures And Electronic Spectra Of All-Boron Fullerene B40, Rongxing He, Xiao Cheng Zeng
Xiao Cheng Zeng Publications
This study is motivated by the recent discovery of the first all-boron fullerene analogue, a B40 cluster with D2d point-group symmetry, dubbed borospherene (Nat. Chem., 2014, 6, 727). Insight into the electronic structures and spectral properties of B40 is timely and important to understand the borospherene and the transition from open-ended plate or ribbon-like structures to a hollow-cage structure at B40. Optimized geometries of borospherene B40 for both the ground state and the first excited state allow us to compute spectral properties including UV-vis absorption, infrared (IR) and Raman spectra. Highly resolved absorption and …
Medium-Sized Au40(Sr)24 And Au52(Sr)32 Nanoclusters With Distinct Gold-Kernel Structures And Spectroscopic Features, Wen Wu Xu, Yadong Li, Yi Gao, Xiao Cheng Zeng
Medium-Sized Au40(Sr)24 And Au52(Sr)32 Nanoclusters With Distinct Gold-Kernel Structures And Spectroscopic Features, Wen Wu Xu, Yadong Li, Yi Gao, Xiao Cheng Zeng
Xiao Cheng Zeng Publications
We have analyzed the structures of two medium-sized thiolateprotected gold nanoparticles (RS-AuNPs) Au40(SR)24 and Au52(SR)32 and identified the distinct structural features in their Au kernels [Sci. Adv., 2015, 1, e1500425]. We find that both Au kernels of the Au40(SR)24 and Au52(SR)32 nanoclusters can be classified as interpenetrating cuboctahedra. Simulated X-ray diffraction patterns of the RS-AuNPs with the cuboctahedral kernel are collected and then compared with the X-ray diffraction patterns of the RS-AuNPs of two other prevailing Au-kernels identified from previous experiments, namely the Ino-decahedral kernel and icosahedral kernel. …
Extremely Strong Tubular Stacking Of Aromatic Oligoamide Macrocycles, Mark A. Kline, Xiaoxi Wei, Ian J. Horner, Rui Liu, Shuang Chen, Si Chen, Ka Yi Yung, Kazuhiro Yamato, Zhonghou Cai, Frank V. Bright, Xiao Cheng Zeng, Bing Gong
Extremely Strong Tubular Stacking Of Aromatic Oligoamide Macrocycles, Mark A. Kline, Xiaoxi Wei, Ian J. Horner, Rui Liu, Shuang Chen, Si Chen, Ka Yi Yung, Kazuhiro Yamato, Zhonghou Cai, Frank V. Bright, Xiao Cheng Zeng, Bing Gong
Xiao Cheng Zeng Publications
As the third-generation rigid macrocycles evolved from progenitor 1, cyclic aromatic oligoamides 3, with a backbone of reduced constraint, exhibit extremely strong stacking with an astoundingly high affinity (estimated lower limit of Kdimer > 1013 M–1 in CHCl3), which leads to dispersed tubular stacks that undergo further assembly in solution. Computational study reveals a very large binding energy (–49.77 kcal mol–1) and indicates highly cooperative local dipole interactions that account for the observed strength and directionality for the stacking of 3. In the solid-state, X-ray diffraction (XRD) confirms that the aggregation of 3 results …
The Role Of Hydroxyl Channel In Defining Selected Physicochemical Peculiarities Exhibited By Hydroxyapatite, Vuk Uskoković
The Role Of Hydroxyl Channel In Defining Selected Physicochemical Peculiarities Exhibited By Hydroxyapatite, Vuk Uskoković
Pharmacy Faculty Articles and Research
Mysteries surrounding the most important mineral for the vertebrate biology, hydroxyapatite, are many. Perhaps the Greek root of its name, απαταo, meaning ‘to deceive’ and given to its mineral form by the early gem collectors who confused it with more precious stones, is still applicable today, though in a different connotation, descriptive of a number of physicochemical peculiarities exhibited by it. Comparable to water as the epitome of peculiarities in the realm of liquids, hydroxyapatite can serve as a paradigm for peculiarities in the world of solids. Ten of the peculiar properties of hydroxyapatite are sketched in this review piece, …
Note: Improved Line Strengths Of Rovibrational And Rotational Transitions Within The X3Σ⁻ Ground State Of Nh, James S.A. Brooke, Peter F. Bernath, Colin M. Western
Note: Improved Line Strengths Of Rovibrational And Rotational Transitions Within The X3Σ⁻ Ground State Of Nh, James S.A. Brooke, Peter F. Bernath, Colin M. Western
Chemistry & Biochemistry Faculty Publications
Recently, a line list including positions and transition strengths was published for the NH X3Σ− rovibrational and rotational transitions. The calculation of the transition strengths requires a conversion of transition matrix elements from Hund’s case (b) to (a). The method of this conversion has recently been improved during other work on the OH X2Π rovibrational transitions, by removing an approximation that was present previously. The adjusted method has been applied to the NH line list, resulting in more accurate transition strengths. An updated line list is presented that contains all possible transitions with v′ and …
The Effect Of Milling Additives On Powder Properties And Sintered Body Microstructure Of Nio, L. Jay Deiner, Michael A. Rottmayer, Bryan C. Eigenbrodt
The Effect Of Milling Additives On Powder Properties And Sintered Body Microstructure Of Nio, L. Jay Deiner, Michael A. Rottmayer, Bryan C. Eigenbrodt
Publications and Research
The evolution of powder particle size, crystal structure, and surface chemistry was evaluated for micron scale NiO powders subjected to impact milling with commonly employed milling additives: methanol, Vertrel XF, and amorphous carbon. The effect of the different comminution protocols on sintered body microstructure was evaluated for high temperature sintering in inert atmosphere (N2). X-ray photoelectron spectroscopy showed that NiO powder surface chemistry is surprisingly sensitive to milling additive choice. In particular, the proportion of powder surface defect sites varied with additive, and methanol left an alcohol or alkoxy residue even after drying. Upon sintering to intermediate temperatures (1100 ℃), …
On The Catalytic Activity Of Palladium Nanoparticles-Based Anodes Towards Formic Acid Electro-Oxidation: Effect Of Electrodeposition Potential, Islam M. Al-Akraa Dr., Ahmad M. Mohammad Prof, Mohamed S. El-Deab Prof, Bahgat E. El-Anadouli Prof
On The Catalytic Activity Of Palladium Nanoparticles-Based Anodes Towards Formic Acid Electro-Oxidation: Effect Of Electrodeposition Potential, Islam M. Al-Akraa Dr., Ahmad M. Mohammad Prof, Mohamed S. El-Deab Prof, Bahgat E. El-Anadouli Prof
Chemical Engineering
In this investigation, the catalytic activity of palladium nanoparticles (PdNPs)-modified glassy carbon (GC) (simply noted as PdNPs/GC) electrodes towards the formic acid electro-oxidation (FAO) was investigated. The deposition of PdNPs on the GC substrate was carried out by a potentiostatic technique at different potentials and the corresponding influence on the particles size and crystal structure of PdNPs as well as the catalytic activity towards FAO was studied. Scanning electron microscopy (SEM) demonstrated the deposition of PdNPs in spherical shapes and the average particle size of PdNPs deposited at a potential of 0 V vs. Ag/AgCl/KCl(sat.) was the smallest (ca. 8 …
Advances In Direct Formic Acid Fuel Cells: Fabrication Of Efficient Ir/Pd Nanocatalysts For Formic Acid Electro-Oxidation, Islam M. Al-Akraa, Ahmad M. Mohammad, Mohamed S. El-Deab Prof, Bahgat E. El-Anadouli Prof
Advances In Direct Formic Acid Fuel Cells: Fabrication Of Efficient Ir/Pd Nanocatalysts For Formic Acid Electro-Oxidation, Islam M. Al-Akraa, Ahmad M. Mohammad, Mohamed S. El-Deab Prof, Bahgat E. El-Anadouli Prof
Chemical Engineering
No abstract provided.