Materials Literature
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The homogeneity of the polymer hybrid was controlled by Diels−Alder reaction. The polymer hybrids were prepared from styrene copolymer bearing pendent furan moieties (20%) and tetraethoxysilane using maleimide silane coupling agent by a sol−gel process. Styrene copolymer was synthesized by free radical copolymerizatio…
When cationic surfactants are added to the Stöber process, spherical particles with radially oriented mesopores can be prepared by precipitation of silica from a solution of ethanol, water, and ammonia. Van Tendeloo and co-workers proposed that these particles form by epitaxial growth of cylindrical assemblies from th…
Abstract Aim Document the biogeographical distributions of diatoms in the Canadian Arctic in relation to environmental factors. Location The Canadian Arctic Archipelago. Methods Diatoms were extracted from lake sediments and treated using standard methods. Rarefaction‐estimated species richness, diatom concentrations…
The copolymer of styrene-maleic acid (SMA) was used to construct micelles containing pirarubicin (4'-O-tetrahydropyranyladriamycin, or THP) as a new anticancer drug formulation. The procedure for the preparation of the micelles was simple, the component consisting of only SMA and pirarubicin in a noncovalent associati…
Generation 3 PAMAM dendrimers functionalized with 2,3-naphthalimide chromophoric groups on the end branches were synthesized, and the formation of Eu3+ polymetallic complexes was investigated. The luminescence properties of these complexes upon binding were fully characterized. On addition of Eu3+ to the dendrimer sol…
Escherichia coli dihydrofolate reductase (DHFR) has several flexible loops surrounding the active site that play a functional role in substrate and cofactor binding and in catalysis. We have used heteronuclear NMR methods to probe the loop conformations in solution in complexes of DHFR formed during the catalytic cycl…
Abstract Limited information is available on microporosity in soils. A study was undertaken to investigate the micropore characteristics of four soil samples, with different particle-size distributions, and four natural silicate clay minerals. Specific surface area and the differential micropore-size distribution were…
Synthetic entry has been achieved into high oxidation state Mn-Ca cluster chemistry with the preparation of [Mn(13)Ca(2)O(10)(OH)(2)(OMe)(2)(O(2)CPh)(18)(H(2)O)(4)]; the structure contains [Mn(4)CaO(4)] sub-units similar to that found in the photosynthetic water oxidizing complex.
The preparations and structures of LAlOCH(2)C(S)HMeCl, where L = (R,R) or (S,S)-N,N'-bis(3,5-di-tert-butyl-salicylidene)-1,2-cyclohexenediamino, are reported together with the respective LAlOEt compounds, and their reactivities toward L- and rac-lactides in various solvents reveal the surprising complexity of the ster…
The two-loop temperature hysteresis of integrated intensity of Raman scattering of light is explained theoretically for a line of frequency 50 cm-1 in a superconducting oxide Ba1-xKxBiO3 single crystal.
We have studied the electronic states in 1-5 layers thick Ag films on V(100), by means of ab initio density functional calculations. Due to the mismatch of the electronic structure of Ag and V, quantum well states of both sp and d character localized on Ag films are formed. We find that the hybridization of the Ag qua…
The effects of oxygen adsorption on the reflectance anisotropy spectrum (RAS) of reconstructed Si(100):O surfaces at sub-monolayer coverage (first stages of oxidation) have been studied by an ab initio DFT-LDA scheme within a plane-wave, norm-conserving pseudopotential approach. Dangling bonds and the main features of…
X-ray diffuse scattering in the vicinity of a basis-forbidden (200) Bragg reflection was measured for a sample with uncapped self-assembled Ge islands epitaxially grown on Si(001). Our results provide evidence of atomically ordered SiGe domains in both islands and wetting layer. The modeling of x-ray profiles reveals…
We present a perturbative model for crystal-field calculations, which keeps into account the possible mixing of states labelled by different quantum number J. Analytical J-mixing results are obtained for a Hamiltonian of cubic symmetry and used to interpret published experimental data for actinide dioxides. A unified…
The energy spectrum of the quantum Klein-Gordon lattice is computed numerically for different nonlinear contributions to the Hamiltonian. In agreement with the studies on the effective Hubbard Hamiltonian for boson quasi-particles (see for instance Refs.\onlinecite{AGRANOVICH,Eilbeck}) a pairing of the phonon states i…
Cobalt ferrite, CoFe 2 O 4, nanoparticles have been obtained from pre-prepared layered double hydroxide carbonate, LDH-CO 3, by mechanical milling. X-ray powder diffraction shows the only product of the milling for 5 h of the LDH-CO 3 is cobalt ferrite nanoparticles. Longer-term milling induces particle growth charact…
Highly cross-linked narrow or monodisperse poly(divinylbenzene) (PDVB) microspheres were prepared by distillation−precipitation polymerization as a novel polymerization technique in acetonitrile with 2,2‘-azobis(2-methylpropionitrile) (AIBN) as initiator. The polymeric microspheres were formed simultaneously through a…
The reactivity of the surface species present over a 2%Pt/CeO 2 catalyst during the reverse water-gas-shift (RWGS) reaction was investigated by a detailed operando spectrokinetic analysis. A single reactor common for the kinetic and the spectroscopic measurements was used. The reactor employed was a modified high-temp…
The concept of shape-controlled synthesis is discussed by investigating the growth mechanisms for silver nanocubes, nanowires, and nanospheres produced through a polymer-mediated polyol process. Experimental parameters, such as the concentration of AgNO(3) (the precursor to silver), the molar ratio between poly(vinylp…
We consider many-particle diffusion in 2D colloidal suspensions with hydrodynamic interactions within a mode-coupling approach. We focus on the behaviour of the effective scaled collective diffusion coefficient D C (ρ)/ D 0 as a function of the density of the colloids ρ, where D 0 is the single-particle diffusion coef…