Graft copolymerization of acryl-amide onto guar-gum has been carried out in the presence of potassium per sulphate as a redox initiator. The prepared graft copolymer was characterized by various techniques such as FT-IR, SEMEDX and TGA-DTA-DTG. Activated charcoal was also studied as the adsorbent in the present study to evaluate their adsorption capacity for Cr (Vl) and compared it with indigen...

cylindrical thin-walled tubes due to construction and easy installation, high energy absorption capacity are used in the automotive industry as an impact energy absorber. however, the main weakness of cylindrical tubes is in the high initial peak load. therefore, in this paper, to overcome this weakness, a buckling initiator is used at the top of the tube. this buckling initiator is a steel rod...

increasing the thermal stability and resistance to bacterial attack (bioresistance) of the potato starch used in the water-based drilling fluid is the aim of this work. four types of potato starch grafted with acrylamide and a mixture of each one with acrylic acid, 2-acrylamido-2-methyl-1-propane sulfuric acid and itaconic acid were synthesized by manganese (iv)-induced redox system at the suit...

Impairment of energy metabolism is a hallmark of brain aging and several neurodegenerative diseases, such as the Alzheimer’s disease (AD). Ageand disease-related hypometabolism is commonly associated with oxidative stress and they are both regarded as major contributors to the decline in synaptic plasticity and cognition. Neuroinflammatory changes, entailing microglial activation and elevated e...

quinones are a class of compounds which have widespread importance in chemistry, biology and medicine. because of their appropriate performance in electron transferring rate, quinones are among the most applicable mediators in biosensors. recently, the effects of different non-metal substitutions on redox potential of quinone have been investigated to design suitable mediators for different ele...

Four variations of the Koch curve are presented. In each case, similarity dimension, area bounded by fractal and its initiator, volume revolution about initiator calculated. A range classroom exercises proved to allow students investigate fractals further.

Many organisms control initiation of DNA replication by limiting supply or activity of initiator proteins. In plasmids, such as P1, initiators are limited primarily by transcription and dimerization. However, the relevance of initiator limitation to plasmid copy number control has appeared doubtful, because initiator oversupply increases the copy number only marginally. Copy number control inst...

The initiator element of the adenovirus type 2 IVa2 promoter is sufficient to direct accurate initiation by RNA polymerase II. Analysis of the effects of substitution of specific base pairs on initiator activity in in vitro transcription systems indicated that specific sequences between positions -4 and +5 were essential for initiator activity. Mutations that impaired or eliminated initiator ac...

Two methionine tRNAs from yeast mitochondria have been purified. The mitochondrial initiator tRNA has been identified by formylation using a mitochondrial enzyme extract. E. coli transformylase however, does not formylate the yeast mitochondrial initiator tRNA. The sequence was determined using both 32P-in vivo labeled and 32P-end labeled mt tRNAf(Met). This tRNA, unlike N. crassa mitochondrial...