Solvent free oxidation of primary alcohols and diols using thymine iron(III) catalyst

In this study, we developed an efficient and selective iron-based catalyst system for the synthesis of ketones from secondary alcohols and carboxylic acids from primary alcohol. In situ generated iron catalyst of thymine-1-acetate (THA) and FeCl(3) under solvent-free condition exhibits high activity. As an example, 1-octanol and 2-octanol were oxidized to 1-octanoic acid and 2-octanone with 89% and 98% yields respectively.     

Synthesis and characterization of some new C2 symmetric chiral bisamide ligands derived from chiral Feist's acid

The hemilabile chiral C2 symmetrical bidentate substituted amide ligands (1R,2R)-5(a-d) and (1S,2S)-6(a-d) were synthesized in quantitative yield from (1R,2R)-(+)-3-methylenecyclo-propane-1,2-dicarboxylic acid (1R,2R)-3 and (1S,2S)-(-)-3-methylene-cyclopropane-1,2-dicarboxylic acid (1S,2S)-3, in two steps, respectively. The chiral Feist's acids (1R,2R)-3 and (1S,2S)-3 were obtained in good isomeric purity by resolution of trans-(±)-3-methylene-cyclopropane-1,2-dicarboxylic acid from an 8:2 mixture of tert-butanol and water, using (R)-(+)-α-methylbenzyl amine as a chiral reagent. This process is reproducible on a large scale. All these new synthesized chiral ligands were characterized by 1H-NMR, 13C-NMR, IR, and mass spectrometry, as well as elemental analysis and their specific rotations were measured. These new classes of C2 symmetric chiral bisamide ligands could be of special interest in asymmetric transformations.     

An optimal symbolic calculus on Besov algebras

In this paper we consider Besov algebras on , that is Besov spaces for s>1/p. For s>1+(1/p), p>4/3, and qp we prove that the above algebras have a maximal symbolic calculus in the following sense: for any function f belonging locally to and such that f(0)=0, the associated superposition operator T_f(g):=f○g takes to itself.     

<Superscript>29</Superscript>Si MAS-NMR study of oxide conductors derived from the apatite-type La<Subscript>9.33</Subscript>Si<Subscript>6</Subscript>O<Subscript>26</Subscript> compound

The preparation of (La_9.33−2x/3Sr _x □_0.67−x/3)Si₆O₂₄O₂ (0 ≤ x ≤ 2) samples with different amounts of cation vacancies is reported. Structure and unit-cell parameters were deduced by Rietveld analysis of XRD patterns. Structural features that enhance oxygen conductivity in Sr-doped apatites are discussed. Up to three components were detected in ²⁹Si MAS-NMR spectra which change with the amount and distribution of cation vacancies. In general, oxygen conductivity increases with the amount of vacancies at La1 (6h) sites, passing through a maximum for x = 0.4. In the case of activation energy, a minimum is detected near x = 1.2, indicating that entropic and enthalpic change in different ways. The presence of cation vacancies should enhance oxygen hopping along c-axis; however, the analysis of the frequency dependence of conductivity suggests that oxygen motions are produced along three axes.     

Hydrogel‐Forming and Dissolving Microneedles for Enhanced Delivery of Photosensitizers and Precursors

We present “one‐step application” dissolving and hydrogel‐forming microneedle arrays (MN) for enhanced delivery of photosensitizers/precursors. MN (280 μm) prepared from 20% w/w poly(methylvinylether/maelic acid) and cross‐linked with glycerol by esterification to form hydrogels upon skin insertion, or allowed to dissolve rapidly in skin, were combined with patches containing 19 mg cm^?2 of 5‐aminolevulinic acid (ALA) or meso‐tetra (N‐methyl‐4‐pyridyl) porphine tetra tosylate (TMP) for drug delivery. Both MN types were mechanically robust, with compression forces of 20.0 N only causing height reductions of 14%. Application forces as low as 8.0 N per array allowed >95% of the MN in each array type to penetrate excised porcine skin, with the MN penetrating to approximately 220 μm. MN significantly enhanced transdermal delivery of ALA and TMP in vitro, with the hydrogel‐forming system comparable with the dissolving system for ALA delivery (approximately 3000 nmol cm^?2 over 6 h), but superior for delivery of the much larger TMP molecule (approximately 14 nmol cm^?2 over 24 h, compared to 0.15 nmol cm^?2). As this technology clearly has potential in enhanced photodynamic therapy of neoplastic skin lesions, we are currently planning animal studies, to be followed by preliminary human evaluations. GMP manufacturing scale‐up is ongoing.     

Elastic α-Nucleus Scattering at 36 to 60 Mev/Nucleon

Working within the framework of the Coulomb modified Glauber model and using the optical limit approximation to evaluate the elastic S-matrix, we use a parameterized effective nucleon-nucleon phase shift function instead of the frequently applied Gaussian parameterization of the nucleon-nucleon scattering amplitude to compute elastic differential cross sections for alpha particles. Our phenomenological ansatz contains three parameters which are adjusted in order to reproduce the alpha nucleus elastic scattering data for one nucleus at each of three beam energies. It is found that once the nucleon-nucleon phase shift function is so calibrated, our model very nicely reproduces elastic alpha scattering data on other nuclei at the same energy.     

The Edge Ideals of Complete Multipartite Hypergraphs

We classify all complete uniform multipartite hypergraphs with respect to some algebraic properties, such as being (almost) complete intersection, Gorenstein, level, l-Cohen-Macaulay, l-Buchsbaum, unmixed, and satisfying Serre's condition S _r , via some combinatorial terms. Also, we prove that for a complete s-uniform t-partite hypergraph ?, vertex decomposability, shellability, sequentially S _r , and sequentially Cohen–Macaulay properties coincide with the condition that ? has t ? 1 sides consisting of a single vertex. Moreover, we show that the latter condition occurs if and only if it is a chordal hypergraph.     

Growth and design of novel nonlinear optical material (NLO) ⿿ Glycine barium nitrate potassium nitrate (GBNPN) crystal

A potentially useful semi organic nonlinear optical (NLO) material ? glycine with barium nitrate and potassium nitrate (GBNPN) has been synthesized by slow evaporation technique. Good transparent GBNPN crystals were obtained in a time span of 3 weeks. The grown crystals were characterized by single crystal/powder XRD, UV?vis?IR absorption, FTIR, thermal analysis and powder SHG measurements have been studied. The grown crystals were thermally stable up to 137.53 °C. The GBNPN crystal exhibits second harmonic generation efficiency of about 1.35 times than that of potassium di hydrogen phosphate (KDP). Mechanical properties such as micro hardness (H_v) and Mayer's index, n, have been carried out by indentation method. The refractive index (μ) has been measured by the Brewster's angle method.