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81.
Péter Sallay László Farkas Zoltán Szlovák István Rusznák Péter Bakó Mohamed Ahmed Antal Tungler Gabriella Fogassy 《Journal of surfactants and detergents》2002,5(4):353-357
Homogeneous nonionic surfactants were produced by the ethoxylation of a selected unit of a homolog series. These particular
products are of use for the analysis of nonionics and for the determination of surface characteristics. A new general method
for the synthesis of homogeneous nonionic surfactants is described. Ethylene glycol monobenzyl ether was repeatedly reacted
in Williamson synthesis (or esterified with acid chlorides in the first step), followed by hydrogenolysis with alkyl- or aralkyl
alcohols, phenols, carboxylic acids, and amines. Homogeneous nonionics can be synthesized by this method, whereas the conventionally
produced ones are usually inhomogeneous. 相似文献
82.
Béla Szentpáli Gábor Matyi Péter Fürjes Endre László Gábor Battistig István Bársony Gergely Károlyi Tibor Berceli 《Microsystem Technologies》2012,18(7-8):849-856
This work is intended to describe the design aspects and to characterize the functionality of a novel thermopile structure applicable for detecting millimetre range and THz radiation. The proposed thermopile consists of a series of micromachined poly-crystalline silicon thermocouple strips arranged linearly. This device can act as a series of antennas; its antenna-like operation was demonstrated clearly by the strong polarization dependence when detecting microwave radiation. The sensing principle is similar to the basic operation of bolometers in that the absorbed radiation heats up the semiconductor strips, but the temperature increment is detected by the Seebeck effect instead of the resistance change. Therefore there is no read-out current and the voltage output starts from zero. In the present work we are going to show the simulation of the current distribution. The fabrication of the device will also be outlined, as well as the results of measurements performed at 13, 100?GHz, and both in broad-band THz and in infrared radiation. 相似文献
83.
István Vajda 《International Journal of Information Security》2016,15(4):403-412
We consider the analysis of time-aware cryptographic protocols in the universal composability (UC) framework (Canetti in 2000). The tasks we consider are the timeliness of messages within an instance as well as the time of validity of cryptographic credentials where the lifetime of time stamps overlaps lots of instances. We point out that the UC analysis of time-aware protocols with global access to real time clock cannot be carried out directly within the standard model. For the resolution of the corresponding problem, we considered two ways: one is the introduction of an auxiliary timing oracle into the ideal system, while the other consists of two time models: a quantized real time source and an abstract “random-time” source, and we show an essential equivalence between them. The time models provide not only theoretical but also practical benefits. 相似文献
84.
Ákos Horváth Gábor Bergmann István Ráth Dániel Varró 《International Journal on Software Tools for Technology Transfer (STTT)》2010,12(3-4):211-230
As recent tool contests demonstrated graph transformation tools scale up to handle very large models for model transformations, thanks to recent advances in graph pattern matching techniques. In this paper, we assess the performance and capabilities of the Viatra2 model transformation framework by implementing the AntWorld case study of the GraBats 2008 graph transformation tool contest. First, we extend initial measurements carried out in Bergmann et al. (Proceedings of ICMT ’09, 2nd International Conference on Model Transformation, Springer, Berlin, 2009) to assess the effects of combining local search-based and incremental pattern matching strategies. Moreover, we also assess the performance characteristics of various language features of Viatra2 as well as the cost of certain model manipulation operations. We observe by experimentation how Viatra2 can scale up to large iteratively growing model sizes and focus on execution time and memory consumption. We believe that the results obtained from the benchmark example can set the course for further performance enhancement of Viatra2 and other future model transformation frameworks. 相似文献
85.
Wang Q Leino E Jancsó A Szilágyi I Gajda T Hietamäki E Lönnberg H 《Chembiochem : a European journal of chemical biology》2008,9(11):1739-1748
The ability of the dinuclear Zn2+ complex of 1,4-bis[(1,5,9-triazacyclododecan-3-yloxy)methyl]benzene (L(1)) to promote the cleavage of the phosphodiester bond of dinucleoside-3',5'-monophosphates that contain a guanine base has been studied over a narrow pH range from pH 5.8 to 7.2 at 90 degrees C. Comparative measurements have been carried out by using the trinuclear Zn2+ complex of 1,3,5-tris[(1,5,9-triazacyclododecan-3-yloxy)methyl]benzene (L(2)) as a cleaving agent and guanylyl-3',5'-guanosine (5'-GpG-3') as a substrate. The strength of the interaction between the cleaving agent and the starting material has been elucidated by UV spectrophotometric titrations. The speciation and binding mode have been clarified by potentiometric titrations with hydrolytically stable 2'-O-methylguanylyl-3',5'-guanosine and 1H NMR spectroscopic measurements with guanylyl-3',5'-guanosine. The results show that the guanine base is able to serve as a site for anchoring for the Zn2+-azacrown moieties of the cleaving agents L(1) and L(2), analogously to uracil base. The interaction is, however, weaker than with the uracil base and, hence, only the 5'-GpG-3' site (in addition to 5'-GpU-3' and 5'-UpG-3' sites) is able to markedly modulate the phosphodiester cleavage by the Zn2+ complexes of di- and trinucleating azacrown ligands containing an ether oxygen as a potential H-bond-acceptor site. 相似文献
86.
We consider the torsion problem of a circular cylindrical bar which is filled up with composite spherical inclusions. The composite inclusions consist of a core and coating both of which are spherically orthotropic with the volume fractions of the core being the same in every composite inclusion. The center points of the spherical inhomogeneities are on the axis of revolution of the circular cylinder. The neutral inhomogeneity in the considered problem of elastic equilibrium is defined as a foreign body (inclusion) which can be introduced in a host body without disturbing the elastic field (displacements, stresses) in it. The conditions of the neutral inhomogeneity for the twisted circular cylindrical bar are derived, and some special cases of inhomogeneity are analyzed. The present paper gives a new example for neutral inhomogeneity in the field of elasticity. 相似文献
87.
88.
Ferenc Rudolf Tóth Zoltán Ladányi Gergely Siket István Gyimóthy Tibor 《Software Quality Journal》2020,28(4):1447-1506
Software Quality Journal - Bug datasets have been created and used by many researchers to build and validate novel bug prediction models. In this work, our aim is to collect existing public source... 相似文献
89.
We have studied the sampling performance of conformational search programs using geometric and energetic criteria. Ideally, a conformational search algorithm should identify the largest possible number of low-energy structures (energy criterion) covering the widest possible range of molecular shapes (geometric criterion). Geometric analysis consisted in comparing the distribution of conformations within the generated ensembles by multidimensional scaling and by analysing the eigenvalue structure of the pairwise coordinate covariance matrices. The energetic comparison was carried out by assessing the energy distribution of conformers after minimizing them all using the same semi-empirical quantum mechanics optimization protocol. The present investigation focused on five conformational search programs: DGEOM, QXP, ROTATE, LMOD and OMEGA. We have applied these methodologies to a maximally diverse 604-compound subset of the LeadQuest library. The program LMOD performs best according to the energetic criterion, whereas a wider range of geometrically diverse conformations is sampled by the other programs, at the cost of higher median conformer energies. In terms of speed, OMEGA is fastest. We recommend the use of LMOD or OMEGA for high-quality conformational search applications. 相似文献
90.
We propose an estimation method to fit conics and quadrics to data in the context of errors-in-variables where the fit is subject to constraints. The proposed algorithm is based on algebraic distance minimization and consists of solving a few generalized eigenvalue (or singular value) problems and is not iterative. Nonetheless, the algorithm produces accurate estimates, close to those obtained with maximum likelihood, while the constraints are also guaranteed to be satisfied. Important special cases, fitting ellipses, hyperbolas, parabolas, and ellipsoids to noisy data are discussed. 相似文献