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Additional Series (additional + series)
Selected AbstractsPrediction of gas-phase 13C nuclear magnetic shielding constants using ONIOM and optimally selected basis functionsCONCEPTS IN MAGNETIC RESONANCE, Issue 6 2008M. Tafazzoli Abstract The wave functions for calculating gas-phase 13C nuclear magnetic shielding constants of 22 molecules have been optimally selected using factorial design as a multivariate technique. GIAO and CSGT methods were used for computation of shielding constants. Different wave functions for different types of carbons were recommended. A wave function as the best level of the theory is proposed for almost similar carbons. ONIOM approach for molecules with different types of carbons is applied. The results of GIAO method using the proposed wave function are in very good agreement with the experimental values. An additional series (21 carbons) were used as test sets and their results confirmed the validity of the approaches. © 2008 Wiley Periodicals, Inc.Concepts Magn Reson Part A 32A: 449,461, 2008. [source] P16 Eyelid dermatitis with positive patch test to coconut diethanolamideCONTACT DERMATITIS, Issue 3 2004Yves Dejobert Objective:, The aim was to detect a possible allergen in a patient with eyelid dermatitis. Patient and methods: a non atopic 27-year-old female presented with eyelid dermatitis since 3 months. This dermatitis persisted despite the fact she had stopped the use of make up; she had acrylic artificial nails since 2 months and sometimes used hair dyes;patch tests were performed with Finn Chamber® tests with readings at D2 and D3, according ICDRG criteria, with European standard series, additional series (including toluenesulfonamide formaldehyde resin), cosmetic, acrylates, hairdressing series, in 3 patch test sessions, using Chemotechnique Diagnostics® allergens. Results:, The only positive patch test was coconut diethanolamide (0.5% pet.)++ at D2 and D3. After removal of the shampoo containing this allergen, the dermatitis cleared. Coconut diethanolamide (cocamide DEA), tensioactive synthesized with coconut oil is widely used in shampoos, soaps, shower gels, barrier creams, washing up liquids, metalworking fluids, hydraulic oils. Involvement of eyelids is not frequently described in the literature with this allergen. Conclusion:, Coconut diethanolamide should be added in cosmetic series, and it should be useful to test this allergen in patients with eyelid dermatitis. [source] Stepwise geographical traceability of virgin olive oils by chemical profiles using artificial neural network modelsEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 10 2009Diego L. García-González Abstract The geographical traceability of virgin olive oils implies the use of analytical methods that allow the identification of the origin of the oil and the authentication of the information boasted on the labels. In this work, the geographical identification of the virgin olive oils has been addressed by complete chemical characterisation of samples (64 compounds analysed by GC and HPLC) and the design of artificial neural network (ANN) models for each one of the levels of a proposed classification scheme. A high number of samples (687) from Spain, Italy and Portugal served as training and test sets for the ANN models. The highest classification level, focused on the grouping of samples by country, was achieved through analysis of fatty acids, with 99.9% of samples classified. Other levels (region, province, Protected Designations of Origin or PDO) were focused on Spanish oils and required additional series of compounds (sterols, alcohols, hydrocarbons) as well as the fatty acids to obtain classification rates higher than 90%. The classification of oils into different PDOs , the last and most difficult level of classification , showed the highest root mean square errors. The classification percentages, however, were still higher than 90% in the test set, which proves the application of the traceability methodology for a chemical verification of PDO claims. [source] Characterization of the combustion products in large-scale fire tests: comparison of three experimental configurationsFIRE AND MATERIALS, Issue 2 2001Per Blomqvist The storage of large amounts of polymers and other bulk chemicals is a potential hazard in the case of fire. There is at present a lack of knowledge about the implications of such fires. In particular the role of the ventilation conditions on fire chemistry has warranted investigation. A set of indoor, large-scale combustion experiments, conducted on five different materials is described in this article. The main test series was conducted using the ISO 9705 room, where both well-ventilated and under-ventilated conditions were attained by restricting the opening of the room. The degree of ventilation was determined using a phi meter. Furthermore, in addition to measuring the traditional fire-related parameters, extensive chemical characterization of the combustion products was made. Two additional series of experiments were also performed. In one series of tests the size of the enclosure was increased and the fuel was placed in a storage configuration to simulate a real storage situation. In the other test series, three of the materials were tested as large-scale open pool fires. The results from the three configurations are compared regarding yields of combustion products as a function of the degree of ventilation. For a number of toxic combustion products a clear dependence of the production on the equivalence ratio was found. Further, placing the fuel in a storage configuration did not significantly change the outcome of the combustion. Thus, the ISO 9705 room is of a size and scale that can be taken as a model for representing real-scale fires. Additionally it has been demonstrated that an advantage of the ISO 9705 room is the ability to alter the ventilation conditions. Copyright © 2001 John Wiley & Sons, Ltd. [source] QSAR model for alignment-free prediction of human breast cancer biomarkers based on electrostatic potentials of protein pseudofolding HP-lattice networksJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 16 2008Santiago Vilar Abstract Network theory allows relationships to be established between numerical parameters that describe the molecular structure of genes and proteins and their biological properties. These models can be considered as quantitative structure,activity relationships (QSAR) for biopolymers. The work described here concerns the first QSAR model for 122 proteins that are associated with human breast cancer (HBC), as identified experimentally by Sjöblom et al. (Science 2006, 314, 268) from over 10,000 human proteins. In this study, the 122 proteins related to HBC (HBCp) and a control group of 200 proteins that are not related to HBC (non-HBCp) were forced to fold in an HP lattice network. From these networks a series of electrostatic potential parameters (,k) was calculated to describe each protein numerically. The use of ,k as an entry point to linear discriminant analysis led to a QSAR model to discriminate between HBCp and non-HBCp, and this model could help to predict the involvement of a certain gene and/or protein in HBC. In addition, validation procedures were carried out on the model and these included an external prediction series and evaluation of an additional series of 1000 non-HBCp. In all cases good levels of classification were obtained with values above 80%. This study represents the first example of a QSAR model for the computational chemistry inspired search of potential HBC protein biomarkers. © 2008 Wiley Periodicals, Inc. J Comput Chem 2008 [source] Kinetic Reaction Models for the Selective Reduction of NO by Methane over Multifunctional Zeolite-based Redox CatalystsCHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 12 2004T. Sowade Abstract Kinetic measurements of the selective catalytic reduction (SCR) of NO by methane were performed over CeO2/H-ZSM-5, In-ZSM-5, and CeO2/In-ZSM-5 catalysts. The parameter space covered NO, CH4, and O2 concentrations varying from 250 to 1000 ppm, from 500 to 2000 ppm, and from 0.5 to 10,vol.-%, respectively, space velocities between 5000 and 90000 h,1 and temperatures between 573 and 873 K depending on the catalyst activities. With CeO2/In-ZSM-5 an additional series of measurements was performed with moistened feed gas (0.5,10,vol.-% H2O). On the basis of a pseudo-homogeneous, one-dimensional fixed-bed reactor model, the data were fitted to a kinetic model that includes power rate laws for the reduction of NO and for the unselective total oxidation of methane. From analyses of isothermal data sets, almost all reaction orders were found to vary significantly with changing temperature, which indicates that the simple kinetic model cannot reflect the complex reaction mechanism correctly. Nevertheless, the data measured with In-ZSM-5 could be modeled with good accuracy over a wide range of reaction temperatures (150 K) while the accuracy was less satisfactory with the remaining data sets, in particular for data with the moist feed over CeO2/In-ZSM-5. With the latter catalyst it was not possible to represent the data measured in dry and in moist feed in a single model even upon confinement to fixed reaction temperatures. A comparison of the separate models established showed strong changes in the reaction orders in the presence of water, which occur apparently already at a very low water content (,,0.5,vol.-%). The kinetic parameters found are in agreement with earlier conclusions about the reaction mechanisms. With In-ZSM-5, both reaction orders and the activation energy show a rate-limiting influence of NO oxidation on the NO reduction path which is removed by the presence of the CeO2 promoter. A difference in the reaction mechanism over CeO2/In-ZSM-5 and CeO2/H-ZSM-5 is reflected in different kinetic parameters. The differences of the kinetic parameters between dry-feed and moist-feed models for CeO2/In-ZSM-5 reflect adsorption competition between the reactants and water. [source] | |||||||||||||