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151.
Anton Kokalj 《Electrochimica acta》2010,56(2):745-755
The often used approach in the corrosion inhibition studies employing quantum chemical calculations that relies on the correlation between molecular electronic structure parameters and inhibition effectiveness is critically examined. It is shown that the inhibition performance of three selected triazole-based corrosion inhibitors for copper - 3-amino-1,2,4-triazole (ATA), benzotriazole (BTAH), and 1-hydroxybenzotriazole (BTAOH) - cannot be explained on this basis in a sound manner. As the effectiveness of inhibitors is due to several phenomena, the outcome depends on the interplay between them and although molecular electronic parameters may provide many necessary elements, the involved effects can be estimated only approximately which may not always suffice. This supports the proposition that in general molecular electronic properties cannot be directly related to inhibition effectiveness - the actual relation is more involved - thus emphasizing the importance of a rigorous modeling of the inhibitor-surface interaction in the corrosion inhibition studies. 相似文献
152.
O. V. Okatova L. N. Andreeva I. A. Strelina N. N. Ul’yanova A. Yu. Leykin A. L. Rusanov 《Polymer Science Series C》2010,52(1):17-23
Molecular hydrodynamics and optical methods have been employed to study the properties of molecules of polybenzimidazoles
in 96% H2SO4 and to determine their molecular, conformational, and dynamo-optical characteristics. The temperature dependence has been
investigated for the intrinsic viscosity. The equilibrium rigidity of molecular chains has been estimated for the examined
polybenzimidazoles. 相似文献
153.
Susan D. Urban Michael K. Tschudi Suzanne W. Dietrich Anton P. Karadimce 《Journal of Intelligent Information Systems》1999,12(1):27-60
This paper describes the implementation of the Refined Triggering Graph (RTG) method for active rule termination analysis and provides an evaluation of the approach based on the application of the method to a sample active application. The RTG method has been defined in the context of an active-deductive, object-oriented database language known as CDOL (Comprehensive, Declarative, Object Language). The RTG method studies the contents of rule pairs and rule cycles in a triggering graph and tests for: (1) the successful unification of one rule's action with another rule's triggering event, and (2) the satisfiability of active rule conditions, asking whether it is possible for the condition of a triggered rule to evaluate to true in the context of the triggering rule's condition. If the analysis can provably demonstrate that one rule cannot trigger another rule, the directed vector connecting the two rules in a basic triggering graph can be removed, thus refining the triggering graph. An important aspect in the implementation of the method is the development of a satisfiability algorithm for CDOL conditions. This paper presents the tool that was developed based on the RTG method, describing how techniques from constraint logic programming are integrated with other techniques for testing the satisfiability of rule triggering conditions. The effectiveness of the approach within the context of a sample application is also addressed. 相似文献
154.
Nanocomposite magnet of Nd10Fe84-xB6lnx (x=0,1) has been fabricated and magnetic properties have been in vestigated. Addition of indium damages the magnetic behavior, but can change its heat-treatment effect. Annealing does not improve the properties very much to the In-free magnet, but changes the intrinsic coercivity of Nd10Fe83B6ln obviously. 相似文献
155.
156.
Anton V. Polotai Tae-Hee Jeong Gai-Ying Yang Elizabeth C. Dickey Clive A. Randall Pascal Pinceloup Abhijit S. Gurav 《Journal of Electroceramics》2009,23(1):6-12
Multilayer ceramic capacitors based on BaTiO3 dielectric compositions and Ni inner electrodes have complex interfacial reactions that impact the continuity of the inner
electrode microstructure. Previously we demonstrated that through the addition of Cr to Ni, a significant improvement in the
continuity of ultra-thin Ni electrodes in Ni–BaTiO3 multilayer capacitors could be achieved. Here, the effect of the Cr addition to the nickel electrode pastes is studied with
regard to the electrical properties. Low-field electrical measurements demonstrate no major differences between Cr doped Ni
and undoped Ni. However, high-field measurements show a significant decrease to the total capacitor resistance. Under a critical
electrical bias the conductivity significantly increases due to a Fowler–Nordheim tunneling conduction though the interfacial
Schottky barrier at the dielectric–electrode interface; the onset voltage of this conduction is much lower than with the undoped
nickel. Based on these results, we evaluate criteria for the selection of an appropriate refractory metal in order to improve
the Ni electrode continuity. 相似文献
157.
Jorge A. Vieyra Salas Anton A. Darhuber 《Chemical Engineering and Processing: Process Intensification》2011,50(5-6):583-588
We studied evaporation rates of volatile liquids deposited onto chemically patterned surfaces by means of experiments and numerical simulations. We quantified the influence of the droplet geometry, in particular circular, triangular, rectangular and square shapes, as well as the influence of contact angles. We considered the two cases of vaporization both in stagnant atmospheres as well as in the presence of well-defined laminar airflows. While lateral air-convection enhances evaporation, it causes a dependence of the evaporation rate on the pattern orientation with respect to the airflow. Neighboring droplets and rivulets tend to mutually reduce their evaporation rate relative to isolated patterns. 相似文献
158.
A Oulad-Ali V Kirchner A Lobstein B Weniger R Anton D Guillaume Z Charrouf 《Canadian Metallurgical Quarterly》1996,59(2):193-195
Drs. John Elce and Peter Davies, biochemists at Queen's University, Kingston, Ont., are investigating the molecular structure of calpain, an enzyme that has been implicated in the cellular damage that occurs after such events as myocardial infarction and stroke. This damage is precipitated by an imbalance in the regulation of calpain that arises as an indirect result of ischemia. Elce and Davies hope that their research, which involves techniques such as recombinant DNA technology and x-ray crystallography, will lead to the development of a calpain inhibitor that will prevent such damage from occurring and enhance recovery. 相似文献
159.
Ecaterina Andronescu Maria Ficai Georgeta Voicu Denisa Ficai Maria Maganu Anton Ficai 《Journal of materials science. Materials in medicine》2010,21(7):2237-2242
Our purpose was obtaining and characterizing a complex composite system with multifunctional role: bone graft material and
hyperthermia generator necessary for bone cancer therapy. The designed system was a magnetite enriched collagen/hydroxyapatite
composite material, obtained by a co-precipitation method. Due to the applied electromagnetic field the magnetite will induce
hyperthermia and cause tumoral cell apoptosis. The complex bone graft system was characterised by XRD, FTIR and SEM, while
the hyperthermia was quantify by measuring the temperature increase due to the applied alternative electromagnetical field. 相似文献
160.
A security extension for IEEE Std 1149.1 is proposed. It provides a locking mechanism which prevents unauthorised users to
interfere via test bus with the system normal operation. The security extension requires small hardware overhead and allows
full conformance with IEEE Std 1149.1. 相似文献