1652.6 and 1652.5 cm −1 in Se-enriched and non-enriched fruit bodies of P. cornucopiae , respectively ( Fig. 3B ). FT-IR spectra of proteins from all four Pleurotus spp. indicated an increase in flexibility, unfolding and hydrophilicity upon Se
Authors:T. Kovács, Z. Bihari, A. Hargitai, I. Mécs, and K. L. Kovács
The changes of cell surface hydrophilicity in Bacillus subtilis were analyzed in response to oxygen-limitation, heat shock, salt stress, pH-shock, phosphate- and carbon-limitation. Although cell surface hydrophilicity varied during growth phases, an increase of surface hydrophilicity was observed under several of these stress conditions. An observed drop in intracellular GTP and/or ATP may be an element of the signal transduction pathway leading to an increase in surface hydrophilicity in response to environmental stresses. Attachment of cells to soil particles under salt stress conditions is strongly influenced by the degS/degU two-component system, which thereby provides a mechanism for the bacteria to escape from the hostile environment.
This paper presents the measurements of bulk density, matrix density, total open porosity, water absorption coefficient, water vapor diffusion resistance factor and thermal conductivity of hydrophilic mineral wool Front — Rock Max E. Front — Rock Max E consisted of two layers fasten together, namely a low-density and high-density layer.
Authors:Giuseppina Castronuovo, V. Elia, and Filomena Velleca
Enthalpies of dilution of ternary aqueous solutions containing glucose and alkan-1-ols, alkan-1,2-diols and alkan-m,n-diols were determined at 298.15 K by flow microcalorimetry. The pair-wise cross interaction coefficients of the virial expansion of the excess enthalpies were evaluated: they are positive and depend in a complex manner on the length of the alkyl chain of the alkanols. The behaviour of these systems is interpreted in terms of preferential interactions between the hydrophilic groups of the alkanols and the destructured domain present on glucose.
Authors:Yu. Bolbukh, P. Kuzema, V. Tertykh, and I. Laguta
High-density polyethylene, its composites with hydrophilic/hydrophobic silica and the antioxidant BHT (butylated hydroxytoluene)
were studied using the thermogravimetric analysis. It has been shown that filling with silica as well as introducing BHT into
the unfilled polymer increases the thermal-oxidative stability of the polymer. Immobilized BHT is inactive and it suppresses
the stabilizing effect of hydrophobic silica surface in the processes of thermal oxidation at the initial stage. However,
being gradually released from the surface antioxidant prolongs the resistance of the polymer against oxidation.
the global optimum (D less than 1) is also changed. This paper presents for the first time a new way of using the Deringer function of desirable responses where the global optimum is examined in integer values of critical factors. Hydrophilic
Formation and characterization of hydrogel of a hydrophilic polymer in a wide range of gamma absorbed doses is reported. An
aqueous solution contains 2% polyvinyl alcohol (PVA) by mass irradiated under gamma rays of 60Co was chosen for study. The hydrogel was synthesized without using any additives. It was found that gel fraction is an exponential
saturation function that increases with an increase of absorbed dose while swelling ratio is an exponential saturation function
that decreases with an increase of absorbed dose. The results are described by energy transfer model.
Authors:Maria Crişan, Ana Brăileanu, D. Crişan, Mălina Răileanu, N. Drăgan, Diana Mardare, V. Teodorescu, Adelina Ianculescu, Ruxandra Bîrjega, and M. Dumitru
Among the great number of sol-gel materials prepared, TiO2 holds one of the most important places due to its photocatalytic properties, both in the case of powders and coatings. Impurity
doping is one of the typical approaches to extend the spectral response of a wide band gap semiconductor to visible light.
This work has studied some un-doped and Pd-doped sol-gel TiO2 nanopowders, presenting various surface morphologies and structures. The obtained powders have been embedded in vitreous
TiO2 matrices and the corresponding coatings have been prepared by dipping procedure, on glass substrates. The relationship between
the synthesis conditions and the properties of titania nanosized materials, such as thermal stability, phase composition,
crystallinity, morphology and size of particles, and the influence of dopant was investigated.
The influence of Pd on TiO2 crystallization both for supported and unsupported materials was studied (lattice parameters, crystallite sizes, internal
strains). The hydrophilic properties of the films were also connected with their structure, composition and surface morphology.
The methods used for the characterization of the materials have been: simultaneous thermogravimetry and differential thermal
analysis, powder X-ray diffraction, electron microscopy (TEM, SAED) and AFM.
Authors:Aleksandra Radoičić, Helena Majstorović, Tibor Sabo, Živoslav Tešić, and Dušanka Milojković-Opsenica
The chromatographic behavior of twelve neutral, mixed cobalt(III) complexes of the
-edda-type has been investigated in six planar chromatographic systems. Four different stationary phases - unmodified silica gel, CN-silica, cellulose, and alumina - were combined with water-organic solvent (methanol or acetone) binary mobile phases. The effect of the water content of the mobile phases on retention of the complexes was investigation systematically. On the basis of the results obtained, possible separation mechanisms were considered. Hydrophilic-interaction chromatography was assumed to be the mechanism determining separation under normal-phase conditions, i.e. use of mobile phases containing small amounts of water. Reversed-phase chromatography occurs when water-rich mobile phases are used.
Authors:L. Taujenis, V. Olšauskaitė, and A. Padarauskas
A reliable, sensitive and rapid method for determination of nicotine and three minor alkaloids (cotinine, anabasine and nornicotine) in tobacco by ultra-high performance liquid chromatography in hydrophilic interaction chromatography mode coupled with tandem mass spectrometry (HILIC-MS/MS) has been established. HILIC separation was performed on a BEH HILIC column using isocratic elution at 0.5 mL/min with acetonitrile:water (85:15, v/v) mobile phase containing 5 mmol/L ammonium acetate (pH 5.00). Separated analytes were determined by electrospray ionization MS/MS in the positive ion mode using multiple reaction monitoring. Alkaloids from tobacco were extracted in an ultrasonic bath for 10 min with acetonitrile:water mixture (8:2, v/v) containing 5 mmol/L ammonium acetate (pH 5.00). Limits of quantification were 10 μg/g for cotinine, 20 μg/g for anabasine and nornicotine, and 30 μg/g for nicotine. Mean recoveries from tobacco ranged between 94.8% and 104.1% for different analytes with relative standard deviations within 5%. The performance of the proposed method was tested for the extraction and determination of the four alkaloids in cigarette tobacco fillers, and satisfactory results were achieved.