Emission Of Volatile And Semivolatile Organic Compounds From Waterborne Paints – The Effect Of The Film Thickness

A waterborne paint was applied to tin plated steel sheets with three different film thicknesses. The emission of volatile and semivolaile organic compounds ((S) VOCs) from the samples was measured in small climatic chambers under standard conditions over a two-week period. The purpose of the study was to evaluate the effect of the film thickness on the emission rate decay. First order decay models, including sink effects for the high boiling (S) VOCs, were fitted to the concentration versus time data. The results showed that the first order rate constants decrease with increasing film thickness. In uddition, the results indicated that the emissions of the (S)VOCs in the waterborne paint film seemed to be controlled by evaporation. The thicknesses of paint films used in climatic chamber tests to estimate emission rates for product compurison or emission prediction must be known in order to prevent erroneous conclusions     

Recent investigations on some cubic Laves phase compounds of rare earth and transition metals

Pseudobinary alloy, Tb_0·27Dy_0·73Fe_2−δ , belonging to C-15 cubic Laves phase having MgCu₂-type structure, possesses large magnetostriction and high magnetomechanical coupling coefficient. The advantages of this material over existing piezoelectric materials, particularly for SONAR applications, are highlighted. Recent results on the influence of cobalt (Co) on magnetic and magnetomechanical properties of Tb_0·27Dy_0·73Fe₂ are discussed.     

Bioactive compounds in rye flours with different extraction rates

Rye flours with extraction rate of 100% (wholemeal flour), 95% (brown flour), 90% (brown flour) and 70% (light flour) were prepared in order to study the relation between flour extraction rates and content of bioactive compounds. The following compounds were analysed: total phenolic compounds (TPC), total flavonoids (TF), inositol hexaphosphate (IP6), reduced (GSH) and oxidized (GSSG) glutathione, tocopherols (T) and tocotrienols (T3). The reduced/oxidized glutathione status (GSH/GSSG) of the flours was examined as a potential index of flour resistance against oxidative stress. The following observations were made in relation to the flour extraction rates and bioactive compounds contents: (a) milling process caused decrease in content in TPC, TF, IP6, GSH and GSSG, T and T3, (b) the most resistant against oxidation processes were suggested a brown flours, then light and finally wholemeal flour, (c) the ratio of tocotrienols to tocopherols (T3/T) was the highest in rye flours with extraction rate of 100–90% whereas light flour was the poorest source of tocopherols and tocotrienols. The provided data support current trend to increase number of rye products from wholemeal or brown flours.     

光学活性物质的工业生产方法

本文介绍了光学８活性牺牲垢几种工业规模的生产方法及最新的进展，分析了各种方法的特点及存在的问题。     

Characterization of CuInS2 thin films for solar cells prepared by spray pyrolysis

We have made a study of the chemical composition, the electrical, the optical and the structural properties of polycrystalline CuInS₂ thin films prepared by spray pyrolysis to be used for thin film solar cells. These films were deposited starting from aqueous solutions with different chemical compositions ([Cu]/[In] and [S]/[Cu] ratios) and at different substrate temperatures. In all cases, the material is p-type with grains preferentially oriented in the (112) direction of the sphalerite structure. The electro-optical properties show a very strong dependence on the [Cu]/[In] ratio in the solution. Films with copper excess have smaller resistivity and better crystallinity than those which are stoichiometric or have indium excess. The results obtained in this work show the possibility of having CuInS₂ thin films with a wide range of resistivity, a fact that could be important for making solar cells based on this material.     

Drying of persimmons (Diospyros kaki L.) and the following changes in the studied bioactive compounds and the total radical scavenging activities

Fresh persimmons were subjected to two different processes: sun-drying during 1 month and dehydration at 60 °C during 12 h. To assess the effect of this process on nutritional and health-related properties of persimmons dietary fibers, minerals, trace elements, polyphenols and the total radical scavenging activities (TRSAs) were determined before and after processing. It was found that the contents of dietary fibers, minerals and trace elements in fresh and dried persimmons fruits were comparable. Total polyphenols in fresh persimmons was higher than in dried fruits (1.3 vs. 0.9 and 0.8 mg/100 g FW, respectively) and percentage of inhibition was higher than in dried fruits (70% vs. 59% and 55% and 58% vs. 53% and 46% for 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2′-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) [ABTS] radicals, respectively (P>0.05 in all cases). In conclusion: (1) the differences in the contents of dietary fibers, minerals and trace elements in fresh and dried persimmons are not significant; (2) the contents of polyphenols and the level of the TRSA are higher in fresh persimmons than in dried fruits; however, both variables are also high in dried persimmons; (3) when fresh fruits are not available, proper dried persimmons could be used as a valuable substitute.     

Dual reaction capacity of hydrogenated nanodiamond

High temperature hydrogen stream treatment of nanodiamond was shown to produce nanodiamond with bifunctional surface. OH- and different CH-groups were shown to be the main functional groups on the surface. In this article we proposed two main strategies for further chemical modification of hydrogenated nanodiamond. OH-groups were shown to react with different types of acylating agents: anhydrides and chloranhydrides. Chlorination of hydrogenated nanodiamond with molecular chlorine and its subsequent treatment with alkyllithium reagents resulted in formation of alkyl-nanodiamonds. Chlorination was shown to reduce the size of nanodiamonds aggregates. We have also applied suspension-state NMR-H1 spectroscopy to study suspensions of alkyl-nanodiamonds for the first time.     

Influence of carbon introduced by arc melting on the structural and magnetic properties of RFe12−xVx (R = Y and Dy)

Carbon was introduced by arc melting into RFe_12−xV_x compounds, where R = Y or Dy and x = 2, 3 or 4, and its effects on the crystallographic and magnetic properties of these intermetallics were investigated by X-ray, magnetostatic and Mössbauer effect measurements. Experimental results show that the carbon atoms prefer the 4d sites to the 2b sites, or occupy the sites reserved for Fe atoms in the ThMn₁₂-type crystal structure. Carbon solution increases with increasing vanadium concentration, giving rise to an effect opposite to that of vanadium. An increase in vanadium content causes an increase in the cell volume and a linear decrease in Curie temperature and in the Fe magnetic moment, whereas the addition of carbon leads to a reduction in unit volume while maintaining a high T_c and enhancing the Fe magnetic moment despite decreasing iron content in the samples.     

S－148芳醇不饱和聚酯树脂耐腐蚀机理研究

合成了Ｓ－１４８芳醇不饱和聚酯树脂，研究了Ｓ－１４８树脂浇铸体和玻璃钢于不同温度下在不同介质中的耐酸、碱、盐腐蚀性能，并探讨了其耐腐蚀机理。结果表明，Ｓ－１４８树脂具有优异的耐腐蚀性能，可用作耐腐蚀制品的基体树脂。