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11.
Adsorption of CO onto dehydrated cobalt-exchanged ZSM-5 zeolite was studied by CW-EPR techniques. It is shown that the reversible formation of a low spin carbonyl 1{Co(CO)
n
}7 adduct upon addition of carbon monoxide at p
CO>50–60 Torr involves significant change in the spin state of Co2+ from S=3/2 to 1/2. The spin Hamiltonian parameters of the adduct g
x
=2.222, g
y
=2.184, g
z
=2.011, |A
x
|=3.8 mT, |A
y
|=3.2 mT, |A
z
|=7.9 mT were determined by a computer simulation and further discussed in terms of the possible ground state and molecular structure. It is shown that the 1{Co(CO)
n
}7 cage complex exhibits a C2v symmetry with |z
2,2A1 ground state. 相似文献
12.
13.
Wojciech Chmiel Jacek Dańda Andrzej Dziech Sebastian Ernst Piotr Kadłuczka Zbigniew Mikrut Piotr Pawlik Piotr Szwed Igor Wojnicki 《Multimedia Tools and Applications》2016,75(17):10529-10560
Intelligent Transportation Systems (ITS) aim to improve safety, mobility and environmental performance of road transport. The INSIGMA project provides a fresh look at the possible innovations in this field, by enhancing the functionality and accuracy of ITS in urban environments. This paper describes the architecture, sensors, processing algorithms, output modules and advantages of the developed system. A comparison of existing ITS systems has been provided as background. Special attention has been given to performance and privacy issues, as the system includes social aspects such as location monitoring. 相似文献
14.
The practice of service-based manufacturing, utilized in various industries, particularly in electronics, pharmaceuticals, and automotive, is on the rise as it improves enterprise effectiveness in dynamic markets. The mutual responsibilities between the supplier(s) and user(s) of such services are spelled out in defined-time-horizon contracts. While such contracts define mutual obligations of both parties on a tactical/operational level, the long-term strategic objectives of the parties may be in conflict. This paper is focused on studying the dynamics of manufacturing service contracts. It investigates the factors affecting the shape of the negotiation space for such contracts and also the way the space should be navigated in response to changing market conditions. The paper presents an analytical framework developed to facilitate behavior analysis of the actors involved in the contract. 相似文献
15.
Cecilia Laschi Gioel Asuni Eugenio Guglielmelli Giancarlo Teti Roland Johansson Hitoshi Konosu Zbigniew Wasik Maria Chiara Carrozza Paolo Dario 《Autonomous Robots》2008,25(1-2):85-101
This paper presents a sensory-motor coordination scheme for a robot hand-arm-head system that provides the robot with the capability to reach an object while pre-shaping the fingers to the required grasp configuration and while predicting the tactile image that will be perceived after grasping. A model for sensory-motor coordination derived from studies in humans inspired the development of this scheme. A peculiar feature of this model is the prediction of the tactile image. The implementation of the proposed scheme is based on a neuro-fuzzy module that, after a learning phase, starting from visual data, calculates the position and orientation of the hand for reaching, selects the best-suited hand configuration, and predicts the tactile feedback. The implementation of the scheme on a humanoid robot allowed experimental validation of its effectiveness in robotics and provided perspectives on applications of sensory predictions in robot motor control. 相似文献
16.
Zbigniew W. Kowalski 《Journal of Materials Science》1994,29(13):3542-3552
Ion bombardment modification of surface geometrical structure, i.e. surface roughness alteration (Part 1) and changes in surface shape (this paper) are considered. Two surface shape alteration methods, masked and maskless pattern etching, are described. They have been applied to modify various kinds of targets, including metals (99.9% aluminium and 99.9% titanium), metal alloys (stainless steel of 1H18N9T and SS 316 LC), alumina ceramic (96% Al2O3) and Teflon. The results of experiments, where narrow beam glow discharge (GD) and broad beam Kaufman type guns have been used as ion sources, are presented. Approximation of a real surface shape profile by a so-called mean line, which is very helpful in the case of ion patterned but extremely rough surfaces, is also discussed. Finally, the practical aspects of ion bombardment modification of surface shape phenomenon, i.e. its application to sputtering yield and sputtering velocity measurements, are shown. 相似文献
17.
Frida U. Ermawati Suminar Pratapa S. Suasmoro Thomas Hübert Ulrich Banach 《Journal of Materials Science: Materials in Electronics》2016,27(7):6637-6645
A series of Mg1?x Zn x TiO3, x = 0–0.5 (MZT0–MZT0.5) ceramics was synthesised and characterised. The dielectric properties of the samples in the frequency range of 1 Hz–7.7 GHz were explored using three different methods: a contacting electrode method, a parallel-plate method and a perturbed resonator method. The electrical properties in the space charge and dipolar polarisation frequency ranges are discussed in relation to the phase composition and microstructure data. Differences in the zinc substitution divided the dielectrics into two groups, namely MZT0–MZT0.2 and MZT0.3–MZT0.5, each with different amount of a main Mg1?x Zn x TiO3 solid solution phase and a secondary solid solution phase. Zinc substitution promoted the density of the ceramics, improved the purity of the main phase and increased the permittivity for frequencies up to 108 Hz, but reduced the permittivity in the microwave range. In the MZT0.3–MZT0.5 samples, for frequencies less than 1 MHz the quality (Q × f) factors were lower and log σ a.c, the AC conductivity, was higher than for the MZT0–MZT0.2 samples. Above 10 MHz, the (Q × f) factors and log σ a.c of the two groups were similar. 相似文献
18.
19.
Topographs of Corning 7059 glass, developed by 7Kv, 70A Ar+ irradiation from a hollow anode ion gun were investigated. Two forms of surface topography were observed: lens-shaped cavities and waves. These are discussed in terms of measured sputtering yield against incidence angle relation or beam divergence. Practical applications in specimen preparation for transmission electron microscopy and glass homogeneity testing are suggested. 相似文献
20.
Kyoung-Gee Ahn Byung-Kwon Min Zbigniew J. Pasek 《The International Journal of Advanced Manufacturing Technology》2006,29(9-10):929-939
A volumetric error compensation method for a machining center that has multiple cutting tools operating simultaneously has been developed. Due to axis sharing, the geometric errors of multi-spindle, concurrent cutting processes are characterized by a significant coupling of error components in each cutting tool. As a result, it is not possible to achieve exact volumetric error compensation for all axes. To minimize the overall volumetric error in simultaneous cutting, a method to determine compensation amount using weighted least squares has been proposed. This method also allows tolerance distribution of machining accuracy for different surfaces of a workpiece. A geometric error model has been developed using an arch-type, multi-spindle machine tool, and the error compensation simulation results based on this model are presented. The simulation results demonstrated effectiveness of the proposed error compensation algorithm for use with multi-spindle simultaneous cutting applications. 相似文献