A native potato starch was modififi ed with vinyl acetate by graft polymerization in alkaline medium pH 10 the mode of temperature change from 70 to 80°C for 4 hours. The initiator process ammonium persulfate (NH ) 2 S O 8 . conversion 91,5%. chemical structure copolymer (Starch:Vinyl acetate) confifi rmed IR-spectroscopy. Composite materials and triethyl citrate tensile strength 24 MPa were ob...

In order to define factors which determine susceptibility to chemical carcinogenesis, mice sensitive (SENCAR) and resistant (BALB/c) to epidermal carcinogenesis were studied under several treatment conditions for sensitivity to initiation by 7,12-dimethylbenz(a)anthracene or N-methyl-N'-nitro-N-nitrosoguanidine and promotion by 12-O-tetradecanoylphorbol-13-acetate. In newborns of both strains, ...

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...

We report in this paper on the complete structure determination of the modified nucleotide A*, now called Ar(p), that was previously identified in yeast methionine initiator tRNA as an isomeric form of O-ribosyl-adenosine bearing an additional phosphoryl-monoester group on its ribose2 moiety. By using the chemical procedure of periodate oxidation and subsequent beta-elimination with cyclohexyla...

Initiated chemical vapor deposition (iCVD) was explored as a novel method for synthesis of functional polyacrylic thin films. The process introduces a peroxide initiator, which can be decomposed at low temperatures (<2000 C) and initialize addition reaction of monomer species. The use of low temperatures limits the decomposition chemistry to the bond scission of initiator, while retaining funct...

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.

The influence of the monomer's structure on growth mechanisms and performances low dielectric constant insulating thin films elaborated from atmospheric-pressure plasma-enhanced chemical vapour deposition reaction three different tetrasiloxane compounds is elucidated. presence vinyl bonds enables free-radical polymerisation surface pathways, which strongly favoured combination ultrashort plasma...

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...