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Suspension ball-races, which are important elements of steering and suspension systems in vehicles, are manufactured by applying plastic forming technique to assemble the parts after their spherical bearings are designed. In this study, the edge-form rolling process, which is a subsection of the rolling process in manufacturing methods based on plastic forming and used in the manufacturing of the suspension ball-races supplying the motion transmission, was examined comprehensively.

Suspension ball-races, which are important elements of steering and suspension systems in vehicles, are manufactured by applying plastic forming technique to assemble the parts after their spherical bearings are designed. In this study, the edge-form rolling process, which is a subsection of the rolling process in manufacturing methods based on plastic forming and used in the manufacturing of the suspension ball-races supplying the motion transmission, was examined comprehensively.

This article is intended to provide a set of recommended practices for improving of the Time-Domain EMI measurement systems by means of digital signal processing. We have focused on two major aspects: the optimal configuration settings of the direct measurement equipment and the deployment of algorithms to process the measurement result. In that sense, we believe that general purpose time-domain instruments, as oscilloscopes, can be successfully used as an alternative hardware to measure EMI, since they provide accurate and reliable results, surpassing the conventional frequency-domain approach when transient disturbances are present.

The aim of this research was to modify polyamide 6 (PA6) either starting from low molecular weight end modified polymer or high molecular weight commercial grade by solution and/or solid-state polymerization (SSP) without destroying the crystalline phase. Synthetic approach consisted of first molecular mixing of all components in a common solvent preferably followed by SSP below the melting temperature of the PA6. By this way, modification of the backbone occurs in the amorphous phase which is the only mobile part of the polymer at those temperatures. By SSP reactions blocky microstructures are formed instead of random copolymers. In this study, modification of PA6 was mainly done for two purposes: for improved biodegradability and for better properties such as increased Tg. In the first part oligoesters were incorporated in the low molecular weight PA6 chain as hydrolyzable blocks which as a result provide degradability. For this aim two different synthetic routes were followed. The first one was done by making use of isocyanate and amine end groups which are highly reactive already at room temperature. Low molecular weight totally amine end-capped PA6 and totally isocyanate end-capped polycaprolactone diol were synthesized and reacted during the solution mixing in hexafluoroisopropanol (HFIP). High molecular weight multi-block copolymers of PA6-PCL were obtained which were susceptible to degradation either hydrolytically or enzymatically. The second route consisted of base-catalyzed diepoxide oligoester (DEPA)- and low molecular weight carboxyl end-capped PA6 reactions to obtain partially degradable polyesteramides by solution mixing in HFIP followed by complete removal of the solvent and finally SSP. Firstly, model reactions were performed by using polypropylene glycol diglycidyl ether to determine the optimum reaction conditions and later DEPA was used. Here, side reactions and crosslinking prevented obtaining high molecular weight multi-block copolymers as a result of very complicated nature of epoxide-carboxyl reactions. However, multi-block copolymers were achieved consisting of a few blocks of PA6 and oligoester. In the second part of the research, a commercial grade of PA6 was modified with a ‘Nylon salt’ of 1,5-diamino-2-methylpentane (Dytek A) and isophthalic acid (IPA). This modification was also done in the solid state after solution mixing of the salt and PA6. Different amounts of salt were used and melt polymerizations were also performed for comparison. Salt incorporation occurs via aminolysis and acidolysis of PA6. Therefore, in the first stages of the reaction a dramatic decrease in molecular weight is observed which later starts increasing. It was first observed that due to a loss of the volatile diamine mostly acidolysis was taking place which means chain scission by the incorporation of the diacid but not the diamine. This resulted in acid end groups and prevented further increase in molecular weight. For that reason another method was developed to keep the diamine in the mixture. Not only the reaction temperature was lowered but also the reaction was performed in a totally closed environment under Argon until all the diamine was incorporated via aminolysis. In the second stage the reaction temperature was increased and continuous Argon flow was applied to remove the condensation water produced by coupling of the broken chains. This method indeed provided higher molecular weights than before. Molecular and microstructural analysis was done in detail by SEC, 1H and 13C NMR whereas thermal analysis was done by TGA and DSC. Detailed comparison with melt-polymerized random polymer-salt copolymers was performed. It was observed that after SSP reactions the crystalline phase of the PA6 was kept intact while amorphous phase was modified. The degrees of randomness were calculated from NMR and blocky structures were confirmed. Melting points comparable to neat PA6 were achieved and higher Tg values were obtained.

This work describes the synthesis and characterization of polyamide 6 (PA 6)-polycaprolactone (PCL) multiblock copolymers. Low molar mass, fully amine end-capped PA 6 was prepared by the addition of a diamine monomer during e-caprolactam polymerization. A low molar mass PCL was selected to be incorporated as the biodegradable block and was fully end-capped with toluene 2,4-diisocyanate. End group analysis and molecular weight characterizations were performed for both end-functionalized polymers by SEC, NMR and titration analysis. Incorporation of PCL into PA 6 was mainly achieved by solution mixing of the two end-functional blocks and, was continued after the removal of the solvent with solid state polymerization (SSP) by gradual heating until about 40 ??C below the melting temperature of the PA 6. Molecular weights started to grow immediately during solution mixing and only increased marginally during the SSP treatment. FTIR and SEC studies confirmed the reaction between the two components. DSC data, in combination with the enhanced molar mass during solution mixing pointed to a blocky microstructure, for which distinct melting and crystallization temperatures were observed for the PCL and the PA 6 blocks. Hydrolytic and enzymatic degradation studies were performed at 25 ??C where the degree of degradation was followed by weight loss analysis, SEM and SEC.

This study was carried out to investigate the effects of dietary inclusion of shelled acorn seed (Quercus cerris) on the growth performance and carcass yield of Japanese quail (Coturnix coturnix japonica). Four hundred four-day old quail chicks were used in this study. Experimental diets contained 0, 5, 10, 15 or 20% shelled acorn seed. The experiment lasted 38 days. There were no differences between treatments in body weight, body weight gain, feed intake and feed conversion ratio. Furthermore, the mortality rate and carcass yield were not affected by the inclusion in the diet of different levels of shelled acorn seed. The inclusion of shelled acorn seed to the quail diets did not cause any harmful effect on the health of the birds. These results suggested that up to 20% shelled acorn seed could be included as an energy source in quail diets. Keywords: Acorn seed, Coturnix coturnix japonica, growth performanceSouth African Journal of Animal Science Vol. 38 (1) 2008: pp. 38-42

ALTINTAS, Levent/0000-0002-5148-723X; WOS: 000261428900006 The aim of the present study was to compare the effects of Biomin (R) IMBO (combination of probiotic, prebiotic, phytogenic substances and cell wall fragments), of Biotronic (combination of formic and propionic acid based oil an inorganic phyllo-silicate carrier). of it combination of the Biomin (R) IMBO and Biotronic and of all antibiotic, avilamycin, its feed additives on the growth performance, several serum parameters and digestive villus height of quails. A total of 300 1-day-old Japanese quail chicks were randomly divided into 5 experimental groups with 4 replicates of 15 birds per replicate. The experimental design consisted of 5 dietary treatments: 1) a control diet without supplementation-2) it diet with Biomin (R) IMBO at it level of 0.1 kg/100 kg feeds 3) it diet with Biotronic at a level of 0.4 kg/100 kg feed; 4) a diet with a Biomin (R) IMBO and Biotronic combination at levels given above; 5) it diet with avilamycin it( a level of 10 mg/kg feed. Birds consuming diet supplemented with Biomin (R) IMBO, Biotronic and the combination of Biomin (R) IMBO and Biotronic, had a significantly (P

Essiz, Dinc/0000-0002-4759-7858 WOS: 000248379700002 PubMed: 17724933 The purpose of the present study was to evaluate the toxic effects of aflatoxin (AF) on growth performance and various processing parameters of quails and to determine the preventive efficacy of hydrated sodium calcium aluminosilicate (HSCAS). One hundred and eighty 1-d-old quails of both sexes were randomly divided into 4 experimental groups with 5 replicates and 45 birds following weighing.The experimental design consisted of four dietary treatments: 1) control with 0 mg AF/kg of diet and 0 % HSCAS; 2) 0.5 % HSCAS; 3) 2.5 mg AF/kg of diet; 4) 2.5 mg AF/kg of diet plus 0.5 % HSCAS.The chicks were housed in electrically heated battery cages and exposed to light for 24 h from hatching to 3 weeks of age. Quails consumed the diets and water od libitum. Body weight (BW) was significantly (p < 0.001) increased by addition of HSCAS to AF diet. The lowest BW gains in groups received AF alone was observed at all periods. The reduction in BW gain caused by 2.5 mg AF/kg of diet was significantly (p < 0.001) diminished by the addition of 0.5 % HSCAS to the diet. The addition of HSCAS to the AF diet significantly (p < 0.001) protected against decrease of feed intake at all periods with exception of the first period. None of the treatments altered significantly the feed conversion ratio (FCR).The relative weights of the liver, kidney and spleen were increased in the chickens consuming the AF alone diet. However, light microscopic examination demonstrated the addition of HSCAS to quail feed to partially decrease fat deposition caused by the toxin, and besides, electron microscopic examination of indicated a reorganization in the encloplasmic reticulum and increase in the number of ribosomes and polisomes. Furthermore, the decrease in the antibody titre induced by Newcastle vaccine, due to aflatoxins, was relatively prevented. No significant differences were observed for serum total protein, total cholesterol and glucose levels. The results of indicate that HSCAS is effective in preventing the deleterious effects of AF

WOS: 000236113800020 A new nicotinamide complex of Fe(H) cation was prepared by reaction between ferrous sulfate and nicotinamide in aqueous solution. The complex was characterized on the basis of elemental analysis, FT IR and UV-VIS spectroscopy, electrochemistry (cyclic voltammetry) and X-ray crystallography. The complex consists of the molecular composition of [Fe(nicotinamide)(2)(H2O)(4)]center dot [Fe(H2O)(6)]center dot(SO4)(2)center dot 2H(2)O. The complex crystallizes in the monoclinic space group P2(1)/c [a = 12.862(3), b = 7.110(3), c = 16.382(3) angstrom; beta = 95.79(2)degrees]. It has been proven that nicotinamide is coordinated to Fe(H) through the nitrogen atom of its heterocyclic ring.

This research focuses on developing a virtual classroom on a Web using recent development tools. When combined with other network tools Web can be used to create a virtual classroom to bring together a community of learners for interactive education. In this paper we discuss moving some of educational instructions of the Institute of Science Dokuz Eylid University to the Web. This objective is achieved by investigating the use of emerging new development tools and network technologies for creating the neccessary tools to make online collaboration for students.

PubMed: 15133524 [No abstract available]

Ibrahim, Abdul Razak/0000-0002-1982-9375; Naumov, Pance/0000-0003-2416-6569; Fun, Hoong Kun/0000-0001-9970-067X; Jovanovski, Gligor/0000-0002-1041-6275 WOS: 000180534500020 Four different coordination patterns were observed following the partial or complete thermodynamically-controlled ligand substitution of the hydrated tetraaquabis(o-sulfobenzimidato-N)copper(II) complex with heterocyclic bases as examined by X-ray diffraction. The N-heterocycle directs the o-sulfobenzimidate (saccharinate) anion into the immediate coordination polyhedron of the metal by any of the imido, carbonyl or sulfonyl functionalities, or as a lattice counter-ion in the crystal lattice. Aqua(o-sulfobenzimidato-O)tetrakis(4-methylpyridine)copper(II) o-sulfobenzimidate hemihydrate (1) crystallizes in the monoclinic space group P2(1)/n [a = 14.7858(2), b = 16.9090(1), c = 26.2350(2)Angstrom; beta = 92.861(1)degrees], aquadi(o-sulfobenzimidato-N)bis(4-propylpyridine)copper(II) (2) in the tetragonal space group P4(2)/n [a = 15.4127(l), c = 13.4604(1) Angstrom], diaquatetrakis(3-(2-propenyl)imidazole)copper(II) di-o-sulfobenzimidate (3b) in the monoclinic space group P2(1)/c [a = 9.3959(5), b = 28.029(2), c = 8.8763(3) Angstrom; beta = 111.175(1)degrees] and di(o-sulfobenzimidato)tetra(isoquinoline)copper(II) (4b) in the orthorhombic space group Pna2(1) [a = 23.2132(6), b = 11.5760(2), c = 17.6297(4) Angstrom]. The copper atom in 1 is six-coordinate in a distorted trans-N(4)O(2)Cu octahedron with elongated copper-oxygen bonds [Cu-O(water) = 2.462(3), Cu-O(sulfonyl) = 2.567(3) Angstrom]. This adduct represents the first example of a combined O(sulfonyl)/ionic coordination of the o-sulfobenzimidate ion in the same crystal. The copper atom in 2 is five-coordinate in the form of a N(4)OCu square pyramid [Cu-O(water) = 2.238(5) Angstrom]. In 3, the o-sulfobenzimidate anions are linked to the copper atom through the coordinated water molecule forming a distorted octahedral N(4)O(2)Cu environment. In 4, the copper atom is nearly octahedrally coordinated by four nitrogen atoms and a pair of o-sulfobenzimidate carbonyl oxygen atoms. The structural details of the o-sulfobenzimidate coordination pattern correspond well with the 298 and 77 K FT IR spectra of the adducts. The structures of two other solid adducts, tris(3-(2-propenyl)imidazole)copper(II) di-o-sulfobenzimidate trihydrate (3a) and diaquabis(o-sulfobenzimidato-N)bis(isoquinoline)copper(II) (4a) have been predicted by their spectral features. Alteration of the o-sulfobenzimidate coordination mode upon changing the heterocycle ligand shows that this moiety is as a convenient polyfunctional structural tool for the construction of functional solids.

Naumov, Pance/0000-0003-2416-6569 WOS: 000175268400005 Joint spectroscopic (ESR, electronic absorption and FT IR) and voltammetric (square-wave and cyclic voltammetry) techniques were employed to investigate the properties of copper adducts with cysteine, N-acetylcysteine and methionine under aerobic and anaerobic conditions. The metal oxidation state in the solid and solvated adducts adheres to the presence of oxygen, whereas ESR results (g(parallel to) = 2.245, g(perpendicular to) = 2.059, A(parallel to) = 170 Gauss) reveal tetragonally distorted octahedral copper(II) environment under aerobic circumstances. In presence of the thiol and thioether ligands under nitrogen voltammetric measurements evidence formation of copper(I) species.