Characterizations for General Besov-Type Space in Clifford Analysis

In this paper, we obtain some characterizations for general Besov-type spaces by employing certain power series satisfying certain growth conditions in lieu of the weight function in Clifford analysis. The obtained results extend and generalize the corresponding results which are given in [6, 23].     

Experimental and analytical investigation of liquid sheet breakup characteristics

The main objective of this research is to study analytically and experimentally the liquid sheet breakup of a flat fan jet nozzle resulting from pressure-swirling. In this study the effects of nozzle shape and spray pressure on the liquid sheet characteristics were investigated for four nozzles with different exit widths (1.0, 1.5, 2.0 and 2.5 mm). The length of liquid sheet breakup, liquid sheet velocity and the size of formed droplets were measured by a digital high speed camera. The breakup characteristics of plane liquid sheets in atmosphere are analytically investigated by means of linear and nonlinear hydrodynamic instability analyses. The liquid sheet breakup process was studied for initial sinuous and also varicose modes of disturbance. The results presented the effect of the nozzle width and the spray pressure on the breakup length and also on the size of the formed droplets. Comparing the experimental results with the theoretical ones for all the four types of nozzles, gives a good agreement with difference ranges from 4% to 12%. Also, the comparison between the obtained results and the results due to others shows a good agreement with difference ranged from 5% to 16%. Empirical correlations have been deduced describing the relation between the liquid sheet breakup characteristics and affecting parameters; liquid sheet Reynolds number, Weber number and the nozzle width.     

Densities and Viscosities of the Regular Quinary System: Benzene (1) + Toluene (2) + Ethylbenzene (3) + Heptane (4) + Cyclooctane (5) and Its Quaternary Sub-Systems at 293.15 and 298.15 K

The densities and viscosities of the regular quinary system: benzene (1) + toluene (2) + ethylbenzene (3) + heptane (4) + cyclooctane (5), and all its corresponding quaternary sub-systems were measured over the entire composition range at 293.15 and 298.15 K. Kinematic viscosity–composition data reported in the present study were utilized to test the predictive capability of some well-known viscosity models. The models subjected to testing were: the predictive version of the McAllister’s three-body model, a generalized corresponding states principle, the group contribution GC-UNIMOD method, and the Allan and Teja correlation. Results of testing these models led to an overall AAD (%) of 1.20 for the one quaternary system that did not contain cyclooctane, and an overall AAD (%) of 8.59 for the remaining cyclooctane-containing systems. For the quinary system, the overall AAD (%) was found to be 2.92; the last two values were calculated using the value of cyclooctane of 10.595.     

Purification, Sequencing, and Biochemical Characterization of a Novel Calcium-Independent α-Amylase AmyTVE from Thermoactinomyces vulgaris

α-Amylase from Thermoactinomyces vulgaris was highly purified 48.9-fold by ammonium sulfate precipitation, gel filtration on Sephadex G-50 column, and ion exchange chromatography column of DEAE-cellulose. The molecular weight of the enzyme was estimated to be 135 and 145 kDa by SDS–PAGE. Its high molecular weight is due to high glycosylation. The purified amylase exhibited maximal activity at pH 6.0 to 7.0 and was stable in the range of pH 4.0 to 9.0. The optimum temperature for its activity was 50 °C. The enzyme half-life time was 120 min at 50 °C, suggesting intermediate temperature stable α-amylase. The enzyme was sensitive to different metal ions, including NaCl, CoCl₂, and CaCl₂, and to different concentrations of EDTA. The enzyme activity was inhibited in the presence of 1 mM CaCl₂, suggesting that it is a calcium-independent α-amylase. The TLC showed that the amylase hydrolyzed starch to produce large maltooligosaccharides as the main products. A 1.1-kb DNA fragment of the putative α-amylase gene (amy TVE) from T. vulgaris was amplified by using two specific newly designed primers. Sequencing analysis showed 56.2 % similarity to other Thermoactinomyces α-amylases with two conserved active sites confirming its function.     

A Comparative Study of the Effect of Water and Organic Solvents on 1,3-Dipolar Cycloaddition Reactions of Mesitonitrile Oxide with C-Sulfonyl- and Sulfanyl-Dithioformates

1,3-Dipolar cycloadditions of the C-sulfonylated- and sulfanylated-dithioformates with mesitonitrile oxide occurred smoothly in organic and aqueous media to afford 1,4,2-oxathiazoles in good yields. The structures of these cycloadducts have been established via the analysis of NMR data and elemental analyses.     

Spectral Characterization of Novel 3-Phenyl-2-Substituted Quinazoline and Fused Quinazoline Derivatives

3-phenyl-2-thioxo-quinazolin-4(3H)one 1 was utilized for the construction of some novel 2-substituted quinazolin-4(3H)one derivatives through the formation of 2-hydrazinyl quinazolinone, which was used as the key starting material for the synthesis of 2-heteryl quinazolines via the reaction with one carbon donors, β-diketones and β-ketoester. Infrared, ¹H NMR, and mass spectra of the synthesized compounds were discussed. Some of them showed promising anti-inflammatory activity.

Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file.     

Utilization of electric arc furnace dust as an admixture to Portland cement pastes

Electric arc furnace dust (EAFD) is termed as a hazardous waste due to its contamination with heavy metals. Inertization of such very fine dust can be occurred via stabilization and solidification process within the hydrated Portland cement matrix. In this paper, the effect of the addition of various ratios of EAFD on the properties of the hardened Portland cement paste was investigated. Compressive strength, chemically combine water and free lime contents were determined. In addition, phase composition using XRD; DTA analysis; as well as microstructure of the formed hydrates for some selected samples were investigated using SEM. The obtained results showed that the paste containing 1/mass% EAFD give the highest compressive strength values at most hydration ages, specially the later ages, compared to the neat Portland cement blank paste. Whileas, the pastes containing 3 and 5/mass% EAFD showed lower values of compressive strength compared to those of the blank paste.     

Synthesis and Evaluation of Anti-HIV Activity of Mono- and Di-Substituted Phosphonamidate Conjugates of Tenofovir

The activity of nucleoside and nucleotide analogs as antiviral agents requires phosphorylation by endogenous enzymes. Phosphate-substituted analogs have low bioavailability due to the presence of ionizable negatively-charged groups. To circumvent these limitations, several prodrug approaches have been proposed. Herein, we hypothesized that the conjugation or combination of the lipophilic amide bond with nucleotide-based tenofovir (TFV) (1) could improve the anti-HIV activity. During the current study, the hydroxyl group of phosphonates in TFV was conjugated with the amino group of L-alanine, L-leucine, L-valine, and glycine amino acids and other long fatty ester hydrocarbon chains to synthesize 43 derivatives. Several classes of derivatives were synthesized. The synthesized compounds were characterized by 1H NMR, IR, UV, and mass spectrometry. In addition, several of the synthesized compounds were evaluated as racemic mixtures for anti-HIV activity in vitro in a single round infection assay using TZM-bl cells at 100 ng/mL. TFV (1) was used as a positive control and inhibited HIV infection by 35%. Among all the evaluated compounds, the disubstituted heptanolyl ester alanine phosphonamidate with naphthol oleate (69), pentanolyl ester alanine phosphonamidate with phenol oleate (62), and butanolyl ester alanine phosphonamidate with naphthol oleate (87) ester conjugates of TFV were more potent than parent drug TFV with 79.0%, 76.5%, 71.5% inhibition, respectively, at 100 ng/mL. Furthermore, two fatty acyl amide conjugates of tenofovir alafenamide (TAF) were synthesized and evaluated for comparative studies with TAF and TFV conjugates. Tetradecanoyl TAF conjugate 95 inhibited HIV infection by 99.6% at 100 ng/mL and showed comparable activity to TAF (97–99% inhibition) at 10–100 ng/mL but was more potent than TAF when compared at molar concentration.     

Fabrication of Novel Bentonite-Anthracite@Zetag (BT-An@Zetag) Composite for the Removal of Arsenic (V) from an Aqueous Solution

The arsenic (As) pollution of water has been eliminated via intensive scientific efforts, with the purpose of giving safe drinking water to millions of people across the world. In this study, the adsorption of As(V) from a synthetic aqueous solution was verified using a Bentonite-Anthracite@Zetag (BT-An@Zetag) composite. The SEM, FT-IR, XRD, DSC, TGA, and SBET techniques were used to characterize the (BT-An@Zetag) composite. The adsorption of As(V) was explored using batch adsorption under varied operating scenarios. Five kinetic modelswere used to investigate kinetic data, whereas three isotherms had been used to fit empirical equilibrium data. According to the findings, the adsorption mechanism of As(V) was best described by the Freundlich isotherm with a maximum monolayer coverage of 38.6 mg/g showing pseudo-second-order mode. The estimated enthalpy (H°) indicates that the adsorption process is both chemical and endothermic.The calculated free energy (G°) indicates that the reaction is nonspontaneous. After four sequential adsorption cycles, the produced BT-An@Zetag composite demonstrated good reusability and a greater adsorption affinity for As(V) ions. Overall, the BT-An@Zetag composite is suited for removing arsenic from wastewater using adsorption as a cost-effective and efficient technique.