Materials Literature
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gamma-Hexachlorocyclohexane dehydrochlorinase (LinA) is a unique dehydrochlorinase that has no homologous sequence at the amino acid-sequence level and for which the evolutionary origin is unknown. We here propose that LinA is a member of a novel structural superfamily of proteins containing scytalone dehydratase, 3-o…
High-resolution X-ray photoelectron spectroscopy (XPS) has been applied to a series of free-base and Zn-porphyrin polymers in which the macrocycles are separated by oligo(phenylene vinylene) units (OPV) of different, controllable lengths. Neat films of all the Zn-porphyrin polymers unexpectedly reveal two peaks in the…
The electron-density distribution of the high-pressure polymorph of SiO2, stishovite [a = 4.177 (1), c = 2.6655 (5) A, space group P4(2)/mnm, Z = 2], has been redetermined by single-crystal diffractometry using synchrotron radiation of 100.42 and 30.99 keV, respectively, in order to obtain essentially absorption- and…
The reaction of 2,2‘-methylenebis(4-chloro-6-isopropyl-3-methylphenol) (MCIMP-H 2 ) with 1.2 molar equiv of AlMe 3 in THF yields [(MCIMP)AlMe(THF)] ( 1 ), which further reacts with a stoichiometric amount of 2-propanol (IPA), affording the isopropoxy-bridged dimer [(MCIMP)Al(μ-O i Pr)] 2 ( 2 ). Compound 2 can also be…
ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTIsotope Labeling of Carbon Nanotubes and Formation of 12C−13C Nanotube JunctionsLiang Liu and Shoushan FanView Author Information Department of Physics and Tsinghua-Foxconn Nanotechnology Laboratory Tsinghua University, Beijing, 100084, China Cite this: J. Am. Chem. So…
The distribution of the final base damage was determined within isolated DNA exposed to pulses of 266 nm laser light. Studied lesions included oxidation products arising from biphotonic ionization of DNA bases and pyrimidine dimeric photoproducts arising from monophotonic processes. The distribution of the latter clas…
Abstract Surface‐enhanced Raman spectra of 2‐mercaptobenzoxazole (MBO) adsorbed on silver hydrosol were obtained. From the comparison of the SER and normal Raman spectra, both in the solid state and in NaOH solution, it can be deduced that the molecule is dissociatively adsorbed on the silver sol. The similarity betwe…
1,4-Dioxan-2-one (PDX) was polymerized in bulk by means of aluminum triisopropoxide (Al(O i Pr) 3 ) as initiator. Thermodynamic parameters and ceiling temperature were determined from the temperature dependence of the monomer conversion over the range from 60 to 150 °C. It highlights that the thermodynamic equilibrium…
Abstract A series of R(PO 3 ) 3 (R = Ga, In, Y, Sm, Gd, Dy) metaphosphate crystals representing four different structural types were prepared and their vibrational spectra recorded. The distribution of internal and external chain modes was obtained taking into account the configuration (site symmetry) of the polyphosp…
A series of poly(3-hydroxybutyrate-co-4-hydroxybutyrate)s [P(3HB-co-4HB)s] with different 4HB content, biosynthesized by Ralstonia eutropha H16 with mixed carbon sources of 4-hydroxybutyric acid (4HBA) and butyric acid, were fractionated by solvent/nonsolvent fractionation into copolyester fractions with different 4HB…
Fructose-1,6-bis(phosphate) aldolase is an essential glycolytic enzyme found in all vertebrates and higher plants that catalyzes the cleavage of fructose 1,6-bis(phosphate) (Fru-1,6-P(2)) to glyceraldehyde 3-phosphate and dihydroxyacetone phosphate (DHAP). Mutations in the aldolase genes in humans cause hemolytic anem…
We have measured $\mathrm{IV}$ curves of multiwalled carbon nanotubes using end contacts. At low voltages, the tunneling conductance obeys non-Ohmic power law, which is predicted both by the Luttinger liquid and the environment-quantum-fluctuation theories. However, at higher voltages we observe a crossover to Ohm's l…
Based on first principles calculations, we propose a mechanism for the dissociative chemisorption of H2 on carbon nanotubes. The breaking of the H--H bond is concerted with the formation of two C--H bonds on two adjacent carbon nanotubes in solid phase, facilitated by the application of high pressure which shortens th…
Size exclusion chromatography and centrifugation separation protocols were developed and compared for isolating enriched fractions of phenylethynyl-bridged metal nanoparticle dimers and trimers from the monomeric particle starting material. Both methods enabled the isolation of enriched fractions of a desired array wi…
We report the first experimental demonstration that interface microstructure limits diffusive electrical spin injection efficiency across heteroepitaxial interfaces. A theoretical treatment shows that the suppression of spin injection due to interface defects follows directly from the contribution of the defect potent…
An ultrafast paralell data processor is described in which amplitude mode excitations of a charge density wave (CDW) are used to encode data on the surface of a 1-T TaS_2 crystal. The data are written, manipulated and read using parallel femtosecond laser pulse beams, and the operation of a database search algorithm i…
Experiments of Electron Spin Resonance (ESR) were performed on Co$% ^{2+}$ substituting Zn$^{2+}$ or Mg$^{2+}$ in powder samples of Zn$_2$(OH)PO$_4$ and Mg$_2$(OH)AsO$_4$. The observed resonances are described with a theoretical model that considers the departures from the two perfect structures. It is shown that the…
The electronic structure and total energy were calculated for ordered and disordered MgO-CaO solid solutions within the multiple scattering theory in real space and the local density approximation. Based on the dependence of the total energy on the unit cell volume the equilibrium lattice parameter and formation energ…
The development of functional materials with nanometer-scale architectures and the effect of these architectures on their chemical and physical properties are currently of great interest in materials design. Polymerizable lyotropic liquid crystal (LLC) assemblies provide a facile entry into this area by allowing one t…
A new class of epoxy nanocomposites with completely defined organic/inorganic phases was prepared by reacting octakis(glycidyldimethylsiloxy)octasilsesquioxane [(glydicylMe(2)SiOSiO(1.5))(8)] (OG) with diaminodiphenylmethane (DDM) at various compositional ratios. The effects of reaction curing conditions on nanostruct…