One-dimensional metric foliations on the Heisenberg group

We prove that the one-dimensional metric foliations on the -dimensional Heisenberg group equipped with a left invariant metric are homogeneous.

     

Activation energy for the ignition of the catalytic oxidation of methanol in oscillatory regime

The overall activation energy for the ignition of thermokinetic oscillations observed (in a dynamic calorimeter) during the heterogeneous catalytic oxidation of methanol on Pd/LiAl₅O₈ were obtained and discussed by a PdO_x redox cycle.     

Evaluation of kinetic parameters of the thermal decomposition of polyethylene-vinyl acetate graft copolymers

The thermal decomposition of the polyethylene-vinyl acetate graft copolymers was studied by thermogravimetry (nonisothermal conditions, constant heating rate of 4?/min). Between 275 and 350? the thermal decomposition is due to the splitting of the acetoxy groups of the grafted chains and the elimination of acetic acid. The reaction order, activation energy and frequency factor were computed by means of the Coats-Redfern and Fuoss methods. The activation energy and frequency factor valuesobtained with the two methods agree well and they do not depend on the grafted vinyl acetate content (2.6–17.6%).     

Synthesis of a highly fluorinated fatty acid analog

A five-step synthesis of Z-11,11,12,12,13,13,14,14,15,15,16,16,17,17,18,18,18-heptadecafluoro-octadec-8-enoic acid is reported, starting from 1,8-octanediol and 1,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8-heptadecafluoro-10-iododecane. The key step is a Wittig reaction to form the C8-C9 double bond with a Z:E isomeric ratio of 10:1. The route should be generally applicable to the synthesis of highly fluorinated monounsaturated fatty acids.     

Beiträge zum Studium einiger Heterocyclen. XLIV—Massenspektrometrische Untersuchungen einiger 2-(p-X-Phenyl)-5-Y-4-acetylthiazole

The fragmentation under eletron impact of some new 2-phenyl-4-acetyl-thiazoles has been studied. The compounds investigaed exhibit molecular ion peaks. Substituents in the para position of the bensene ring do not influence the fragmentation patterns but only the relative abundances of the molecular ion and some fragment ions. However, by introdicing CI and Br in position 5 of the thiazole some signifiecant differences appear (‘ortho effect’). A rearrangement also occurs involving a 5-membered cyclic transition state. Intense doubly charged ions are obseved a fact which is attributed to the presence of two easily ionizable centres.     

Staining of wool using the reaction products of ABTS oxidation by laccase: synergetic effects of ultrasound and cyclic voltammetry

The effects of ultrasound on 2,2'-Azinobis(3-ethylbenzothiazoline-6-sulfonate) enzymatic oxidation by laccase (Trametes villosa) has been studied by means of cyclic voltammetry. The reaction was allowed to proceed in the presence of a piece of wool and the coloration depth of the wool fabric was measured by means of K/S. It was observed that cyclic voltammetry is influenced the dyeing process and higher K/S values were obtained when the cyclic voltammetry was combined with the ultrasonic irradiation. Moreover, the K/S value is the sum of the values obtained when the wool staining is done in just the presence of cyclic voltammetry or in just the presence of ultrasound. The results obtained on the indigo carmine decolourization gives information on the importance of controlling the amount of ABTS(+) formed during the ultrasonication process.     

Iron Forms Fe(II) and Fe(III) Determination in Pre-Roman Iron Age Archaeological Pottery as a New Tool in Archaeometry

This article presents studies on iron speciation in the pottery obtained from archaeological sites. The determination of iron forms Fe(II) and Fe(III) has been provided by a very simple test that is available for routine analysis involving the technique of molecular absorption spectrophotometry (UV–Vis) in the acid leachable fraction of pottery. The elemental composition of the acid leachable fraction has been determined by inductively coupled plasma optical emission spectrometry (ICP-OES). Additionally, the total concentration of the selected elements has been determined by X-ray fluorescence spectrometry with energy dispersion (EDXRF). The results of the iron forms’ determinations in archaeological pottery samples have been applied in the archaeometric studies on the potential recognition of the pottery production technology, definitely going beyond the traditional analysis of the pottery colour.     

Promising Roles of Alternative Medicine and Plant-Based Nanotechnology as Remedies for Urinary Tract Infections

Urinary tract infections (UTIs) are considered to be the most common infections worldwide, having an incidence rate of 40−60% in women. Moreover, the prevalence of this disorder in adult women is 30 times more than in men. UTIs are usually found in many hospitals and clinical practice; as disorders, they are complicated and uncomplicated; in uncomplicated cases, there is no structural or functional abnormality in the urogenital tract. However, obstruction, retention of urine flow and use of catheters increase the complexity. There are several bacteria (e.g., E. coli, Klebsiella pneumoniae, Proteus vulgaris, etc.) successfully residing in the tract. The diagnosis must not only be accurate but rapid, so early detection is an important step in the control of UTIs caused by uropathogens. The treatment of UTIs includes appropriate antimicrobial therapy to control the infection and kill the causal microbes inside the body. A long-time usage of antibiotics has resulted in multidrug resistance causing an impediment in treatment. Thus, alternative, combinatorial medication approaches have given some hope. Available treatments considered Homeopathic, Ayurvedic, Unani, and other herbal-based drugs. There are new upcoming roles of nanoparticles in combating UTIs which needs further validation. The role of medicinal plant-based nanotechnology approaches has shown promising results. Therefore, there must be active research in phyto-based therapies of UTIs, such as Ayurvedic Biology.