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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.
Ming Li Zbigniew Twardowski Felix Mok Norbert Tam 《Journal of Applied Electrochemistry》2007,37(4):499-504
Sodium dichromate is commonly used in sodium chlorate production to maintain high current efficiency; however, it is also
a well documented carcinogen. To reduce the environmental impact, identification of a suitable alternative with similar buffering
characteristics to dichromate and without adverse effect on the electrolytic performance of sodium chlorate production is
important; sodium molybdate is a good candidate. Molybdate ion and its conjugated acid work as a buffer pair at pH 5–6, a
lower and slightly narrower pH window than the typical buffer region of dichromate. Nonetheless, the molybdate buffer works
effectively during the electrolytic process by maintaining pH at 5.9. Although the use of molybdate buffer will lower the
overpotential of hydrogen evolution reaction (HER) by 100 mV, the average off-gas oxygen content is noticeably compromised
at 3.6–4.6%, measured using a pilot cell operated at 3 kA m−2and 80 °C during a 3-day trial. The resulting current efficiency of 91 92% is significantly lower than when dichromate is
employed as the process additive (> 96%). Mixtures of different dichromate and molybdate ratio were also investigated in terms
of the resulting cathode surface potential. 相似文献
13.
14.
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
15.
Mischa Schmidt Jan Seedorf Stefano Napolitano Rosario G. Garroppo Andrea Cavaliere Thilo Ewald Armin Jahanpanah Zbigniew Kopertowski Marcin Pilarski Pawel Grochocki 《Peer-to-Peer Networking and Applications》2013,6(2):134-154
Application Layer Traffic Optimization (ALTO) has recently gained attention in the research and standardisation community as a way for a network operator to guide the peer selection process of distributed applications by providing network layer topology information. In particular P2P applications are expected to gain from ALTO, due to the many connections peers form among each other, often without taking network layer topology information into account. In this paper, we present results of an extensive intra-ISP trial with an ALTO-enhanced P2P filesharing software. In summary, our results show that—depending on the concrete setting and on the distribution of upload capacity in the network—ALTO enables an ISP to save operational costs significantly while not degrading application layer performance noticeably. In addition, based on our experience we are able to give advice to operators on how to save costs with ALTO while not sacrificing application layer performance at all. 相似文献
16.
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
17.
Kobus Barnard Quanfu Fan Ranjini Swaminathan Anthony Hoogs Roderic Collins Pascale Rondot John Kaufhold 《International Journal of Computer Vision》2008,77(1-3):199-217
We present a new data set of 1014 images with manual segmentations and semantic labels for each segment, together with a methodology
for using this kind of data for recognition evaluation. The images and segmentations are from the UCB segmentation benchmark
database (Martin et al., in International conference on computer vision, vol. II, pp. 416–421, 2001). The database is extended by manually labeling each segment with its most specific semantic concept in WordNet (Miller et al.,
in Int. J. Lexicogr. 3(4):235–244, 1990). The evaluation methodology establishes protocols for mapping algorithm specific localization (e.g., segmentations) to our
data, handling synonyms, scoring matches at different levels of specificity, dealing with vocabularies with sense ambiguity
(the usual case), and handling ground truth regions with multiple labels. Given these protocols, we develop two evaluation
approaches. The first measures the range of semantics that an algorithm can recognize, and the second measures the frequency
that an algorithm recognizes semantics correctly. The data, the image labeling tool, and programs implementing our evaluation
strategy are all available on-line (kobus.ca//research/data/IJCV_2007).
We apply this infrastructure to evaluate four algorithms which learn to label image regions from weakly labeled data. The
algorithms tested include two variants of multiple instance learning (MIL), and two generative multi-modal mixture models.
These experiments are on a significantly larger scale than previously reported, especially in the case of MIL methods. More
specifically, we used training data sets up to 37,000 images and training vocabularies of up to 650 words.
We found that one of the mixture models performed best on image annotation and the frequency correct measure, and that variants
of MIL gave the best semantic range performance. We were able to substantively improve the performance of MIL methods on the
other tasks (image annotation and frequency correct region labeling) by providing an appropriate prior. 相似文献
18.
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
19.
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
20.