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Full-Text Articles in Chemistry
Assessing Secondary And College Students’ Implicit Assumptions About The Particulate Nature Of Matter: Development And Validation Of The Structure And Motion Of Matter Survey, Marilyne Stains, Marta Escriu-Sune, Myrna Lisseth Molina Alvarez De Santizo, Hannah Sevian
Assessing Secondary And College Students’ Implicit Assumptions About The Particulate Nature Of Matter: Development And Validation Of The Structure And Motion Of Matter Survey, Marilyne Stains, Marta Escriu-Sune, Myrna Lisseth Molina Alvarez De Santizo, Hannah Sevian
Chemistry Department: Faculty Publications
Development of learning progressions has been at the forefront of science education for several years. While understanding students’ conceptual development toward “big ideas” in science is extremely valuable for researchers, science teachers can also benefit from assessment tools that diagnose their students’ trajectories along the learning progressions. In this paper, we describe the development and validation of a teacher-friendly survey, the Structure and Motion of Matter (SAMM) survey, designed to measure students’ trajectories along aspects of a research-based learning progression on the particulate nature of matter. Specifically, the survey assesses students’ implicit assumptions about four concepts: the structure of solute …
Synthesis And Isolation Of {110}-Faceted Gold Bipyramids And Rhombic Dodecahedra, Michelle L. Personick, Mark R. Langille, Jian Zhang, Nadine Harris, George C. Schatz, Chad A. Mirkin
Synthesis And Isolation Of {110}-Faceted Gold Bipyramids And Rhombic Dodecahedra, Michelle L. Personick, Mark R. Langille, Jian Zhang, Nadine Harris, George C. Schatz, Chad A. Mirkin
Chemistry Department: Faculty Publications
Two {110}-faceted gold nanostructures—rhombic dodecahedra and obtuse triangular bipyramids—have been synthesized via a Ag-assisted, seed-mediated growth method. The combination of a Cl−-containing surfactant with a low concentration of Ag+ plays a role in the stabilization of the {110} facets. To the best of our knowledge, this is the first reported synthesis of a {110}-faceted bipyramid structure.
Bottom-Up Synthesis Of Gold Octahedra With Tailorable Hollow Features, Mark R. Langille, Michelle L. Personick, Jian Zhang, Chad A. Mirkin
Bottom-Up Synthesis Of Gold Octahedra With Tailorable Hollow Features, Mark R. Langille, Michelle L. Personick, Jian Zhang, Chad A. Mirkin
Chemistry Department: Faculty Publications
Gold octahedra with hollow features have been synthesized in high yield via the controlled overgrowth of preformed concave cube seeds. This Ag+-assisted, seed-mediated synthesis allows for the average edge length of the octahedra and the size of the hollow features to be independently controlled. We propose that a high concentration of Ag+ stabilizes the {111} facets of the octahedra through underpotential deposition while the rate of Au+ reduction controls the dimensions of the hollow features. This synthesis represents a highly controllable bottom-up approach for the preparation of hollow gold nanostructures.
Corrosion Rate Trajectories Of Concreted Iron And Steel Shipwrecks And Structures In Seawater— The Weins Number, Donald L. Johnson, D. J. Medlin, L. E. Murphy, J. D. Carr, D. L. Conlin
Corrosion Rate Trajectories Of Concreted Iron And Steel Shipwrecks And Structures In Seawater— The Weins Number, Donald L. Johnson, D. J. Medlin, L. E. Murphy, J. D. Carr, D. L. Conlin
Chemistry Department: Faculty Publications
The Weins number (Wn) concept is proposed to predict the long-term corrosion rate of wrought iron and steel in seawater for variable marine environments. Plotted as a function of reciprocal absolute temperature, Weins numbers generate a linear plot from which the corrosion rates are calculated when temperature, oxygen concentration, and concretion thickness are known. Application of the theory of absolute reaction rates is described.
Identification And Characterization Of The Anti-Methicillin-Resistant Staphylococcus Aureus Wap-8294a2 Biosynthetic Gene Cluster From Lysobacter Enzymogenes Oh11, Wei Zhang, Yaoyao Li, Guoliang Qian, Yan Wang, Haotong Chen, Yue-Zhong Li, Fengquan Liu, Yuemao Shen, Liangcheng Du
Identification And Characterization Of The Anti-Methicillin-Resistant Staphylococcus Aureus Wap-8294a2 Biosynthetic Gene Cluster From Lysobacter Enzymogenes Oh11, Wei Zhang, Yaoyao Li, Guoliang Qian, Yan Wang, Haotong Chen, Yue-Zhong Li, Fengquan Liu, Yuemao Shen, Liangcheng Du
Chemistry Department: Faculty Publications
Lysobactor enzymogenes strain OH11 is an emerging biological control agent of fungal and bacterial diseases. We recently completed its genome sequence and found it contains a large number of gene clusters putatively responsible for the biosynthesis of nonribosomal peptides and polyketides, including the previously identified antifungal dihydromaltophilin (HSAF). One of the gene clusters contains two huge open reading frames, together encoding 12 modules of nonribosomal peptide synthetases (NRPS). Gene disruption of one of the NRPS led to the disappearance of a metabolite produced in the wild type and the elimination of its antibacterial activity. The metabolite and antibacterial activity were …
Characterizing Rna Dynamics At Atomic Resolution Using Solution-State Nmr Spectroscopy, Jameson R. Bothe, Evgenia N. Nikolova, Catherine D. Eichhorn, Jeetender Chugh, Alexandar L. Hansen, Hashim M. Al-Hashimi
Characterizing Rna Dynamics At Atomic Resolution Using Solution-State Nmr Spectroscopy, Jameson R. Bothe, Evgenia N. Nikolova, Catherine D. Eichhorn, Jeetender Chugh, Alexandar L. Hansen, Hashim M. Al-Hashimi
Chemistry Department: Faculty Publications
Many recently discovered non-coding RNAs do not fold into a single native conformation, but rather, sample many different conformations along their free energy landscape to carry out their biological function. Unprecedented insights into the RNA dynamic structure landscape are provided by solution-state NMR techniques that measure the structural, kinetic, and thermodynamic characteristics of motions spanning picosecond to second timescales at atomic resolution. From these studies a basic description of the RNA dynamic structure landscape is emerging, bringing new insights into how RNA structures change to carry out their function as well as applications in RNA-targeted drug discovery and RNA bioengineering.