Journal of Mathematical and Fundamental Sciences
Not a member yet
737 research outputs found
Sort by
Production and Characterization of Chitinases from Thermophilic Bacteria Isolated from Prataan Hot Spring, East Java
Get PDFThermophilic bacteria producing chitinase were collected from Prataan hot spring, East Java, Indonesia and screened. The isolated bacterium was analyzed using 16S rRNA gene sequencing analysis and identified as Paenibacillus sp. The molecular identification was confirmed through morphological and physiological analyses. The production of chitinase was conducted at various incubation times, temperatures, pH and concentrations of colloidal chitin. The optimum condition of the isolate to produce the highest chitinase was 0.9% (w/v) of colloidal chitin (pH 7.0) at 48 °C for 24 hours. The obtained chitinases were optimally active at 55 °C and pH 6.0-7.0. The chitinases were gradually purified by ammonium sulfate precipitation, Sephadex G-100 gel filtration, followed by DEAE"“cellulose ion exchange chromatography (IEC). The purification method gave a purification factor of 9.43 and a yield of 2.68%. Two protein fractions were obtained from sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) with molecular weights of 68 and 82 kDa
Trees with Certain Locating-chromatic Number
Get PDFThe locating-chromatic number of a graph G can be defined as the cardinality of a minimum resolving partition of the vertex set V(G) such that all vertices have distinct coordinates with respect to this partition and every two adjacent vertices in G are not contained in the same partition class. In this case, the coordinate of a vertex v in G is expressed in terms of the distances of v to all partition classes. This concept is a special case of the graph partition dimension notion. Previous authors have characterized all graphs of order n with locating-chromatic number either n or n-1. They also proved that there exists a tree of order n, n≥5, having locating-chromatic number k if and only if k ∈{3,4,"¦,n-2,n}. In this paper, we characterize all trees of order n with locating-chromatic number n - t, for any integers n and t, where n > t+3 and 2 ≤ t < n/2
Effect of V Dopant on Physicochemical Properties of Vanadium-Doped Anatase Synthesized via Simple Reflux Technique
Get PDFMesoporous pure TiO2 (M-TiO2) and mesoporous-vanadium-doped TiO2 (M-V-doped TiO2) were successfully synthesized via a facile and simple reflux technique. The purpose of this research was to study the effect of vanadium dopant on the physicochemical properties of all materials obtained. Characterization of the prepared materials was carried out using X-ray diffraction (XRD), scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS) and N2-adsorption-desorption analysis. The presence of Ti and O elements in M-TiO2 and of Ti, V and O elements in M-V doped TiO2 could be detected by SEM-EDS, while the patterns of X-ray diffraction of all the prepared samples had a well-crystalline surface of anatase type. All mesoporous vanadium-doped TiO2 (M-V-doped TiO2) materials performed in a highly transparent mode in the visible region at 554 nm (Eg = 2.24 eV) and 588 nm (Eg = 2.12 eV) for 3.3 and 4.9 wt% V doped TiO2, respectively. The Rietveld refinement method was applied to extract the structural parameters of the M-TiO2 and M-V-doped TiO2 using the Fullprof program in the WinPlotr package. The prepared materials were refined in the crystal system and space group of anatase (tetragonal, I41/amd (141)). The vanadium ion was successfully doped into TiO2. The isotherm type of M-TiO2 and 2.3 wt% V doped TiO2 were of type IV, with a profile of type H2 hysteresis loops, while the 3.3 and 4.9 wt% vanadium-doped TiO2 reflected isotherm type III. The Brunauer-Emmett-Teller (BET) results showed a significant reduction in surface area due to increased concentrations of vanadium. The highest values of BET-specific surface area, pore volume and average pore size of M-TiO2 were 46 m2/g, 18.45 nm and 0.2572 cm3/g respectively
Inclusion Properties of Orlicz and Weak Orlicz Spaces
Get PDFThis paper discusses the structure of Orlicz spaces and weak Orliczspaces on â„n. We obtain some necessary and sufficient conditions for the inclusion property of these spaces. One of the keys is to compute the norm of the characteristic functions of the balls in â„n
