Article
Materials Science, Multidisciplinary
Nadia Nabihah Mohd Yusof Chan, Azila Idris, Zul Hazrin Zainal Abidin, Hairul Anuar Tajuddin, Zanariah Abdullah
Summary: This study investigated the photophysical and photochemical properties of a series of furocoumarins, revealing their sensitivity to solvent polarity, intermolecular interactions, and substituent effects. The experimental and theoretical results suggest the potential use of furocoumarins in nonlinear optics applications, highlighting their solvatochromic effects and fluorescence quenching mechanisms.
MATERIALS CHEMISTRY AND PHYSICS
(2022)
Article
Chemistry, Organic
Croix J. Laconsay, Tyler C. Rho, Dean J. Tantillo
Summary: In this study, the hyperconjugation/conjugation through-bond stereoelectronic effects in 3-azabicyclo[3.3.1]nonanes were investigated using density functional theory to explain the puzzling differences in reactivity between a vinylogous chloride and a vinylogous ester.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Physical
Chhayly Tang, Baptiste Auguie, Eric C. Le Ru
Summary: The research investigates the impact of adsorbed molecule orientation and position on the surface of metallic nanoparticles on the sensitivity of localized surface plasmon resonance (LSPR) sensing. Results show that molecules with their main optical axis perpendicular to the surface and located near hot spots can induce a significantly larger resonance shift, suggesting potential improvements in LSPR sensing sensitivity through targeted adsorption at hot spots with carefully engineered molecular orientation.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Geosciences, Multidisciplinary
Tessa Maurer, Francesco Avanzi, Steven D. Glaser, Roger C. Bales
Summary: This study uses the Budyko framework to analyze 30 years of data from 14 basins in California and finds that shifts in the precipitation-runoff relationship during droughts can be decomposed into regime shifts and partitioning shifts. Regime shifts are primarily driven by interannual changes in precipitation or temperature, making them predictable, while partitioning shifts involve further nonlinear and indirect catchment feedbacks, making them harder to predict. Additionally, the study finds that runoff during droughts is influenced by factors such as low aridity, high baseflow, a shift from snow to rain, and resilience of high-elevation runoff.
HYDROLOGY AND EARTH SYSTEM SCIENCES
(2022)
Article
Chemistry, Multidisciplinary
Xiunan Zhang, Jingkang Wang, Fei Yu, Xin Huang, Na Wang, Ting Wang, Hongxun Hao
Summary: A novel flexible red fluorophore, dimethyl 1,2,3,4,6,7,8,9-octahydropyrido[2,3-g]quinoline-5,10-dicarboxylate, with a large Stokes shift up to 231 nm, was designed and synthesized. It exhibits red emission in solution and enhanced red emission in the crystallized state. The butterfly-like tricyclic architecture shows elastic property, acid/base vapor stimulus response, and selective fluorescence detection of Cu2+. This work provides a feasible and efficient strategy for multifunctional fluorophores compared to typical extended pi-conjugated systems.
CRYSTAL GROWTH & DESIGN
(2022)
Article
Engineering, Electrical & Electronic
Jose Orti Gonzalez, Olayiwola Alatise
Summary: This article presents a method for evaluating the implications of threshold voltage (VTH) drift from gate voltage stress in SiC MOSFETs, which uses Miller coupling to characterize the impact of bias temperature instability (BTI)-induced VTH shift. Unlike traditional BTI characterization methods, this approach considers the actual converter environment to study the implications of VTH shift, making it more relevant for applications engineers. Studies on temperature, recovery time, and stress polarity have been conducted on commercially available SiC MOSFETs.
IEEE TRANSACTIONS ON POWER ELECTRONICS
(2021)
Article
Materials Science, Biomaterials
Xing Guo, Bing Tang, Qinghua Wu, Weibin Bu, Fan Zhang, Changjiang Yu, Lijuan Jiao, Erhong Hao
Summary: This study develops a new type of fluorescent probes that are specifically targeted to lipid droplets and lysosomes, with high specificity and good photostability, suitable for bioimaging of lipid droplets and lysosomes.
JOURNAL OF MATERIALS CHEMISTRY B
(2022)
Article
Soil Science
Xiali Mao, Jinyang Zheng, Wu Yu, Xiaowei Guo, Kang Xu, Ruiying Zhao, Liujun Xiao, Mingming Wang, Yefeng Jiang, Shuai Zhang, Lun Luo, Jinfeng Chang, Zhou Shi, Zhongkui Luo
Summary: The temperature sensitivity of soil organic carbon (SOC) decomposition is influenced by both soil depth and elevation. The chemical composition of SOC and its physiochemical protection against decomposition are the major factors that contribute to the variability of SOC decomposition.
SOIL BIOLOGY & BIOCHEMISTRY
(2022)
Article
Plant Sciences
Ahmed Abou El-Yazied, Mohamed F. M. Ibrahim, Mervat A. R. Ibrahim, Ibrahim N. Nasef, Salem Mesfir Al-Qahtani, Nadi Awad Al-Harbi, Fahad Mohammed Alzuaibr, Abdullah Alaklabi, Eldessoky S. Dessoky, Nadiyah M. Alabdallah, Mohamed M. A. Omar, Mariam T. S. Ibrahim, Amr A. Metwally, Karim M. Hassan, Said A. Shehata
Summary: The study found that melatonin has a protective effect on potato plants under drought stress and enhances their antioxidative defense systems. Additionally, melatonin has differential effects on tuber yield, increasing it under drought conditions but decreasing it under well-watered conditions.
Article
Materials Science, Textiles
Xiao Meng, Xuemei Wang, Ping Wang, Dagang Miao, Xin Ning
Summary: Free radical graft polymerization of DADMAC on cotton significantly improves dyeability cotton with reactive dyes under salt-free conditions. The cationization modification enhances the effectiveness of dye fixing and increases the dye uptake rate and dyeing depth compared to conventional dyeing techniques.
FIBERS AND POLYMERS
(2021)
Article
Orthopedics
Xiaotian Yang, Hua Guo, Wenwen Ye, Lin Yang, Chengqi He
Summary: The study showed that pulsed electromagnetic field can attenuate the structural and functional progression of osteoarthritis by inhibiting TNF-alpha and IL-6 signaling. Additionally, the protective effects of PEMF on chondrocyte apoptosis and autophagy are regulated by TNF-alpha and IL-6 signaling.
Article
Chemistry, Multidisciplinary
Carolyn L. Hartley, Melody L. Kessler, Jillian L. Dempsey
Summary: Surface structure and reactivity are crucial for optimizing the properties of nanocrystals. Semiconductor nanocrystals face a technical disadvantage due to the lack of specific chemical formula, requiring innovative approaches to obtain a molecular-level surface image.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Inorganic & Nuclear
Brittany L. Huffman, Katherine J. Lee, Ana M. Geer, Bradley A. McKeown, Xiaofan Jia, Diane A. Dickie, T. Brent Gunnoe, Jillian L. Dempsey
Summary: Electrochemical methods and chemical oxidant-based analytical strategies were used to evaluate the oxidative reactivity of the platinum(II) diimine complex in coordinating and noncoordinating media. The study identified a highly reactive Pt-II radical cation and three reaction pathways that can follow its one-electron oxidation, highlighting the critical role of axial ligation in modulating the competition between radical-radical dimerization and oxidative disproportionation.
Article
Chemistry, Multidisciplinary
Daniel A. Kurtz, Debanjan Dhar, Noemie Elgrishi, Banu Kandemir, Sean F. McWilliams, William C. Howland, Chun-Hsing Chen, Jillian L. Dempsey
Summary: The study investigates the mechanism of hydride formation through two-electron, one-proton reactions of a family of complexes. It reveals that proton transfer rate constants are correlated with the strength of the proton source and the steric bulk of the chelating diphosphine ligands, plateauing as the reaction becomes increasingly exergonic. Mechanistic studies identify the stepwise process of hydride formation involving reduction of Co(III) species, ligand dissociation, protonation, and tautomerization.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Inorganic & Nuclear
Ryan J. Day, Anthony J. Gross, Elizabeth S. Donovan, Kyle D. Fillo, Gary S. Nichol, Greg A. N. Felton
Summary: The structures and properties of five novel iron-based compounds were investigated, with X-ray crystallography revealing the solid-state structure of two of them, carbonyl IR spectra and reduction potentials correlating with Hammett constants of different groups, and compound 5 showing low overpotential activity in the electrocatalytic production of dihydrogen.
Article
Chemistry, Physical
Carolyn L. Hartley, Jillian L. Dempsey
Summary: This study investigates defects on the surfaces of semiconductor quantum dots using redoxactive chemical probes and spectroscopic tools, revealing the impact of different sizes and reductant strengths on ligand displacement, as well as the conclusion that large quantum dots have more native disulfide defects.
CHEMISTRY OF MATERIALS
(2021)
Article
Chemistry, Inorganic & Nuclear
David M. Kaphan, Kelsey R. Brereton, Rachel C. Klet, Ryan J. Witzke, Alexander J. M. Miller, Karen L. Mulfort, Massimiliano Delferro, David M. Tiede
Summary: In this study, photoinduced transfer hydrogenation reactions using Cp*IrH organometallic catalysts were explored, focusing on aqueous ketone reduction catalyzed by [Cp*Ir(bpy)H][Cl]. Detailed mechanistic studies and kinetic analyses of the reduction of cyclohexanone revealed a unique photochemical reaction pathway to ketone reduction distinct from the traditional HER process.
Article
Chemistry, Physical
Michael J. Mortelliti, Annie N. Wang, Jillian L. Dempsey
Summary: The study on the deposition of ultrathin TiOx coatings on TiO2 and SnO2 cores using ALD revealed that after annealing at certain temperatures, the crystallinity and electronic structure of TiOx became closer to crystalline TiO2. In contrast, the TiOx coatings deposited at low temperatures or without annealing exhibited disordered structures with a broad distribution of trap states within the band gap.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Plant Sciences
Tayliz M. Rodriguez, Mawuli Deegbey, Elena Jakubikova, Jillian L. Dempsey
Summary: The ligand-to-metal charge transfer (LMCT) transitions of [Re(dmpe)(3)](2+) were investigated using UV/Vis absorbance spectroscopy, photoluminescence spectroscopy, and time-dependent density functional theory. The solvent dependence of the lowest energy charge transfer transition was quantified, with no solvatochromism observed. TD-DFT calculations revealed that the dominant LMCT transition is highly symmetric and delocalized, involving all phosphine ligand donors in the charge transfer, explaining the absence of solvatochromism in [Re(dmpe)(3)](2+).
PHOTOSYNTHESIS RESEARCH
(2022)
Review
Electrochemistry
Bethany M. Stratakes, Jillian L. Dempsey, Alexander J. M. Miller
Summary: This review discusses the use of molecular catalysts in the synthesis of fuels through electrochemical transformations, emphasizing the evaluation criteria and methods for assessing catalyst efficiency. The need to employ methods that enable meaningful comparisons between molecular catalysts, as well as strategies for minimizing overpotential while maintaining high activity, is highlighted.
Article
Chemistry, Physical
Michael J. Mortelliti, Chiung-Wei Huang, Joanna M. Atkin, Jillian L. Dempsey
Summary: Ternary atomic layer deposition of Sn-doped TiOx and Ti-doped SnOx was conducted, demonstrating deviations from the rule of mixtures in terms of chemical composition and optical properties. This deviation was attributed to the non-ideal surface chemistry of the binary ALD of SnOx. The presence of intra-bandgap states in the films induced enhanced visible absorption and bathochromic shifts in the apparent bandgap.
APPLIED SURFACE SCIENCE
(2022)
Article
Chemistry, Inorganic & Nuclear
Daniel A. Kurtz, Jibo Zhang, Arvin Sookezian, Jeremy Kallick, Michael G. Hill, Bryan M. Hunter
Summary: This report presents a study on a redox series of cobalt complexes in five sequential oxidation states, with characterization using electrochemical, spectroscopic, and crystallographic methods. The use of a simple bidentate phosphine ligand allows for isolation of the five oxidation states, with changes in coordination number and geometry as a function of the oxidation state. Single-crystal X-ray diffraction is used to characterize complexes in each oxidation state.
INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Bethany M. Stratakes, Kaylee A. Wells, Daniel A. Kurtz, Felix N. Castellano, Alexander J. M. Miller
Summary: This study presents a new approach using nickel photoelectrocatalysts for visible-light-driven H-2 evolution, revealing the mechanism and thermodynamic basis through experimental and theoretical analyses. The unique photochemical properties of nickel complexes enable H-2 evolution without electrochemical overpotential, leading to improved rates.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Inorganic & Nuclear
Jack Thomas-Colwell, Arvin Sookezian, Daniel A. Kurtz, Jeremy Kallick, Lawrence M. Henling, Troy A. Stich, Michael G. Hill, Bryan M. Hunter
Summary: We report the isolation and characterization of a series of cobalt(II) bis(phosphine) complexes with varying numbers of coordinated solvent ligands. Comparison of their structures revealed multiple crystallization motifs for divalent cobalt(II) complexes with the same set of phosphine ligands. This study provides a strategy for tuning the axial variability of other ligands on a phosphine scaffold, and proposes a method for designing cobalt phosphine catalysts.
INORGANIC CHEMISTRY
(2022)
Article
Electrochemistry
Jillian L. Dempsey, Catherine M. Heyer, Gerald J. Meyer
ELECTROCHEMICAL SOCIETY INTERFACE
(2021)