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381.
The catalytic combustion of the emission from coke ovens containing various volatile organic compounds (VOCs) and inorganic species over a La0.9Ce0.1CoO3 catalyst is investigated in an integral fixed reactor through several steps. (1) Combustion of a mixture of VOC reveals that the kinetics of total oxidation of methane determines the total VOC conversion. (2) The conversion of methane, in the case of sulfur-free feed is inhibited by H2O and CO2.  相似文献   
382.
BACKGROUND: The miniemulsion polymerization of butyl acrylate initiated by a macromonomeric azoinitiator (macroinimer, MIM) and stabilized by the non‐ionic emulsifier Tween 60 (TW‐60) was investigated. RESULTS: The monomer conversion and the polymerization rate increase with the amount of MIM and then decrease. The desorption rate constants were estimated using the Ugelstad/O'Toole, Gilbert and Nomura models. The Ugelstad/O'Toole and Gilbert models suggest an increase in the kdes value with increasing emulsifier concentration at the highest MIM concentration while the Nomura model proposes no variation in kdes with an increase in both TW‐60 and MIM concentrations. The polymerization rate increases in the following order with regard to initiator: MIM < ammonium persulfate < dibenzoyl peroxide < 2, 2′‐azobisisobutyronitrile. CONCLUSION: The increase in the rate of polymerization can be discussed in terms of both increased particle concentration and the gel effect. The size of the polymer particles decreases and the number of polymer particles increases with both TW‐60 and MIM concentrations. This behaviour is attributed to the formation of a larger number of smaller monomer and/or polymer particles and higher particle nucleation rate. The observed long nucleation period for the MIM‐initiated polymerization is attributed to the creation of a crosslinked structure and the immobilization of MIM chains. Copyright © 2009 Society of Chemical Industry  相似文献   
383.
SONAR(SOund NAvigation and Ranging一声纳)像雷达,光电系统一样广泛用于机器人,导航和目标检测,其基本原理都基于目标和检测器之间的波传输.声纳与雷达和光电系统的不同之处在于声纳是靠声波传输能量.  相似文献   
384.
In this paper, the problem of providing a fully predictable execution environment for critical and hard real-time applications on embedded and DSP-based platforms is studied from the viewpoint of system architecture and operation.We introduce a set of homogenous models for time, signals and tasks, which will further serve as a basis for describing the architecture and operation of a particular hard real-time kernel – “HARETICK”. The kernel provides support for concurrent operation of hard real-time tasks (the HRT execution environment), using non-preemptive scheduling algorithms, along with soft real-time tasks (the SRT environment), using classical, preemptive, priority-based scheduling algorithms.A set of applications has been developed to test the correct operation of the HARETICK kernel according to the theoretical models and to evaluate its abilities to provide high predictability of execution for critical applications. Some of the main testing results are also discussed in the paper.  相似文献   
385.
In this paper a full‐order observer is suggested in order to achieve finite‐time reconstruction of the state vector for a class of linear systems with unknown inputs. The proposed design procedure is a combination of the approaches proposed by Lin & Wang [1] and Trinh & Ha [2]. The resulted observer has been improved, from the robustness point of view, by this paper's authors by using a novel and efficient method; it consists of adding three robustness terms which cancel the negative effect of the uncertainties which can appear in the system. The effectiveness of the suggested design algorithm is illustrated by a numerical example (aircraft lateral motion).  相似文献   
386.
387.
Cognitive functions, motoric expression, and changes in physiology are often studied separately, with little attention to the relationships or correlations among them. The study presented in this paper implements an integrated approach by combining motion capture (action) and EMG (physiological) parameters as synchronized data streams resulting from the action and associated physiological data. The reported experiments were designed to measure the preparatory movement capabilities of the upper extremities. In particular, measurement of changes in preparatory activity during the aging process is of interest in this context, as the attempt is to develop means to compensate for loss of adaptive capabilities that aging entails. To achieve this goal, it is necessary to quantify preparation phases (timing and intensity). Motion capture and EMG parameters were measured when subjects raised their arms without constraint (condition one) and raised their arms while holding a ball (second condition). Furthermore, on comparing aging and young participants, it was confirmed that with aging the temporal relationships between actual movement and the preceding EMG signal change.  相似文献   
388.
A polysaccharide was obtained by fermentation of glycerol in the presence of Pseudomonas spp. bacteria. It was characterized by FTIR spectroscopy, SEC chromatography, conductimetric titrations, and viscometric measurements; its emulsifying activity was tested using various mixtures of a hydrocarbon compound and polymer solution. Based on this polysaccharide, new crosslinked ionic derivatives were synthesized and characterized; their interaction with lysozyme was studied. From the data presented, one can suggest some applications for this new, less expensive polysaccharide—it could be used as a thickener and specific bioemulsifier, while its derivatives—as a support for controlled release of biomolecules. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   
389.
Benzylamine catalytic effect on the cathodic hydrogen evolution in acid aqueous solution has been studied on copper electrode. Experimental results obtained by voltammetric techniques emphasize that the presence of benzylamine in 1 M sulfuric acid solution enhances the hydrogen evolution reaction (HER). In such a solution, benzylamine is protonated and exists as benzylammonium cation. Kinetic parameters of HER have been determined, observing a significant increase of the exchange current in the presence of benzylamine. Also, a decrease of the cathodic transfer coefficient has been noticed. Activation energy for HER has been computed on the basis of the Arrhenius plots. In the presence of benzylamine the activation energy was 33.0 kJ mol−1, whereas without benzylamine a greater value was obtained: 94.6 kJ mol−1. The catalytic effect of benzylamine was confirmed by electrochemical impedance spectroscopy. The considerable diminution of the double layer capacity is a valid proof of the strong adsorption of benzylamine at the Cu - sulfuric acid solution interface, while the reduction of the charge transfer resistance is a symptom of the enhancement of HER. Ab initio molecular modeling of benzylammonium ion showed that, due to a high value of the dipole moment, the molecules are oriented in the most favorable position for the charge transfer reaction, i.e., with the protonated amino group facing toward the electrode.  相似文献   
390.
In the age of ubiquitous technology, humans are reshaped through each transaction they are involved in. AI-driven networks, online games, and multisensory interactive environments make up alternate realities. Within such alternate worlds, users are reshaped as deterministic agents. Technology’s focus on reducing complexity leads to a human being dependent on prediction-driven machines and behaving like them. Meaning and information are disconnected. Existence is reduced to energy processes. The immense gain in efficiency translates as prosperity. Citizens of advanced economies, hurrying in the rhythm of machine-driven interactions, feel entitled to it. Successful at the price of self-awareness, they no longer know what this means. Happiness and prosperity are not consubstantial. Lack of happiness leads to aggression. This is the image of the world as we see it, no longer looking at each other, eye to eye, but screen to screen. The questions eliminated in the process of transferring responsibility from the individual to machines will inevitably become society’s new focus. When the goal is to get everyone to behave like a machine, the Singularity hypothesis becomes self-fulfilling prophecy. If, in addition to having exhausted natural resources, society does not want to end up making the human mind superfluous, it has to seek a better understanding of what makes anticipation possible. As a definitory characteristic of the living, corresponding to its complexity, anticipation can no longer be taken for granted, while every effort is made to reduce complexity for efficiency’s sake. Awareness of the processes conducive to its expression in successful human action will position human beings as masters of their destiny, not slaves of their own making. Antecapere ergo sum might be the counterclaim to Descartes’ Dubito ergo sum. To resist being perfected into oblivion, that is, unsustainable prosperity, means to reclaim the knowledge corresponding to higher levels of complexity.  相似文献   
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