Iron(III) porphyrin catalyzed ionic liquid mediated polymerization of methylmethacrylate

A novel application of iron(III)porphyrin catalyst, 5,10,15,20 ? tetrakis ? (2′,6′‐dichlorophenyl)porphyrinatoiron(III) chloride is reported for the reaction of methyl methacrylate with hydrogen peroxide in imidazolium ionic liquids at ambient temperature. The reaction furnished polymethyl methacrylate in 75–94% yields. The yield of the polymer was optimized upon changing the reaction media, ratio of catalyst, oxidant and substrate, reaction time and quenchers. The polymethyl methacrylate was secured as highly stereoregular with predominantly syndiotactic sequences as analyzed with the aid of NMR (¹H and ¹³C) and infrared spectroscopy. Besides, the number‐average molecular weights (Mn) were attained in the range of 15,000 to 55,000 with narrow polydispersity (~1.1–1.9) as calculated using gel permeable chromatography (GPC).     

ZnO-Templated Selenized and Phosphorized Cobalt-Nickel Oxide Microcubes as Rapid Alkaline Water Oxidation Electrocatalysts

Oxygen electrocatalysis is of remarkable significance for electrochemical energy storage and conversion technologies, together with fuel cells, metal-air batteries, and water splitting devices. Substituting noble metal-based electrocatalysts by decidedly effective and low-cost metal-based oxygen electrocatalysts is imperative for the commercial application of these technologies. Herein, a novel strategy is presented to fabricate selenized and phosphorized porous cobalt-nickel oxide microcubes by using a sacrificial ZnO spherical template and the resulting microcubes are employed as an oxygen evolution reaction (OER) electrocatalyst. The selenized samples manifest desirable and robust OER performance, with comparable overpotential at 10 mA cm⁻² (312 mV) as RuO₂ (308 mV) and better activity when the current reaches 13.7 mA cm⁻². The phosphorized samples exhibit core–shell structure with low-crystalline oxides inside amorphous phosphides, which ensures superior activity than RuO₂ with the same overpotential (at 10 mA cm⁻²) yet lower Tafel slope. Such a surface doping method possibly will provide inspiration for engineering electrocatalysts applied in water oxidation.     

Gold Nanoparticle Ensembles Allow Mechanistic Insights into Electrochemical Processes

Gold‐nanoparticle‐modified electrodes find wide and diverse applications in the area of electrochemistry. We demonstrate for the first time that gold‐nanoparticle‐modified electrodes can provide mechanistic information and we exemplify this with the electrochemical deposition of arsenic(III). Our approach of using nanoparticle ensembles is a facile and economical methodology that provides an alternative to using expensive gold single‐crystal electrodes that require careful surface preparation before each measurement.     

Synthesis,spectroscopic characterization,crystal structure and antifungal activity of thiourea derivatives containing a thiazole moiety

Four novel thiourea derivatives containing a thiazole moiety were synthesized and characterized by IR, ¹H and ¹³C NMR, mass spectrometry and elemental analysis. The crystal structure of 1a was determined from single crystal X-ray diffraction data. It crystallizes in monoclinic space group P2₁/n with unit cell dimensions a = 11.7752(6) Å, b= 3.8677(2) Å, c= 27.4126(13) Å and β = 92.734(5) Å. There is a strong intramolecular hydrogen bond of the type N-H?O, with H?O distance of 2.5869(19) Å. The mass fragmentation pattern has also been discussed. The antifungal activity of the synthesized compounds was studied by broth micro-dilution method and poisoned food technique. The compounds 1b and 1c possessed a broad spectrum of antifungal activity.

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Examples concerning absolute flatness and amalgamation in pomonoids

Flatness properties of acts over monoids have been studied for almost four decades and a substantial literature is now available on the subject. Analogous research dealing with partially ordered monoids acting on posets was begun in the 1980s in two papers by S.M. Fakhruddin, and, after a dormancy period of some 20 years, has recently been rekindled with the appearance of several research articles. In comparing flatness properties of S-acts and S-posets, it has been noted that the imposition of order results in severe restrictions as far as absolute flatness is concerned. For example, whereas every inverse monoid is absolutely flat (meaning all of its left and right acts are flat), even the three-element chain in its natural order, considered as a pomonoid, fails to have this property. It has long been understood that absolutely flat monoids, in particular, inverse monoids, are amalgamation bases in the class of all monoids. The purpose of the present article is to further investigate absolute flatness of pomonoids and to begin to study its connection with amalgamation in that context. T.E. Hall’s results, that amalgamation bases in the class of all monoids have the so-called representation extension property (REP), which in turn implies the right congruence extension property, are first adapted to the ordered context. A detailed study of the compatible orders (of which there are exactly 13) on the three-element chain semilattice U then reveals a wide range of possibilities: exactly four of these orders render U absolutely flat as a pomonoid, two more give it the right order-congruence extension property in every extension (RCEP) (but fail to make it an amalgamation base because of the failure of the ordered analogue of (REP)), and for the remaining seven, even (RCEP) fails.     

Genes within the serotonergic system are differentially expressed in human brain

Background  

Serotonin is an important neurotransmitter with wide-ranging functions throughout the central nervous system. There is strong evidence to suggest that regulation of serotonergic gene expression might be related to genetic variability, and several studies have focused on understanding the functional effects of specific polymorphisms within these genes on expression levels. However, the combination of genotype together with gender and brain region could have an overall effect on gene expression. In this study, we report expression patterns of five serotonergic genes (TPH1, TPH2, 5-HT2A, 5-HT2C, 5-HTT) in seven different human post-mortem brain regions (superior frontal gyrus, superior temporal gyrus, striatum, cerebellum, hippocampus, midbrain and thalamus) using TaqMan™ real-time quantitative PCR. In addition, the effect of genotype and gender on their expression levels was determined.     

Combined effects of heat and chemical reactions on the peristaltic flow of carreau fluid model in a diverging tube

The study of peristaltic flow of a Carreau fluid in a non‐uniform tube under the consideration of long wavelength in the presence of heat and mass transfer is presented. The flow is investigated in a wave frame of reference moving with velocity of the wave c. Two types of analytical solutions have been evaluated (i) perturbation method (ii) homotopy analysis method for velocity, temperature and concentration field. Numerical integration have been used to obtain the graphical results for pressure rise and frictional forces. The effects of various emerging parameters are investigated for five different peristaltic waves. Copyright © 2010 John Wiley & Sons, Ltd.