The effects of H2 in the feed gasses on the Chichibabin condensation of ammonia with formaldehyde and acetaldehyde for pyridine and 3-picolines synthesis were studied in this work. It was observed that over Pt/ZSM-5 a...
The effects of H2 in the feed gasses on the Chichibabin condensation of ammonia with formaldehyde and acetaldehyde for pyridine and 3-picolines synthesis were studied in this work. It was observed that over Pt/ZSM-5 and H-ZSM-5 catalyst hydrogen can moderate the deactivation, depressed the coke formation, slightly lower the initial yield of pyridine bases and increase the selectivity of pyridine over 3-picoline. These effects cannot be simply attributed to the reactant dilution by H2, while are similar as those of spilt-over hydrogen on a Pt/ZSM-5 catalyst on this reaction. These phenomena are taken as the evidence to support the hypothesis that molecular H2 is activated by the pure zeolite during the Chichibabin condensation.
A kind of phosphonium family based IL, [PC6C6C6C14][Tf2N]under several conditions was studied and the nano-structures (Fig.1) were observed using molecular dynamics simulation based on both all-atom and united-atom fo...
A kind of phosphonium family based IL, [PC6C6C6C14][Tf2N]under several conditions was studied and the nano-structures (Fig.1) were observed using molecular dynamics simulation based on both all-atom and united-atom force ***, little uniform and explicit standards for judging the nano-structure, or in another way, the aggregation in ILs have been reported.
Liquid biofuels are seen as one of the few technological solutions currently available to reducing greenhouse gas emissions from *** back the history of biofuels,so-called 1st generation biofuels are essentially based...
Liquid biofuels are seen as one of the few technological solutions currently available to reducing greenhouse gas emissions from *** back the history of biofuels,so-called 1st generation biofuels are essentially based on food stuff such as sugar, starch, and *** greatest disadvantage of 1st generation biofuels is to compete w1th foodproduction for scarce agricultural land and water, so that the amount of biofu els that can be produced from these sources is limited.
Light olefins mainly refer to ethylene and propylene, which are very important organic chemical materials, and are key intermediates of various chemical materials such as synthetic plastic and chemical fiber.
Light olefins mainly refer to ethylene and propylene, which are very important organic chemical materials, and are key intermediates of various chemical materials such as synthetic plastic and chemical fiber.
The crevice corrosion of the Ni/Graphite abradable sealing coating with open porous for engine of aircrafts will happen,when it serves in marine environment.A simulated occluded corrosion cell was used to study chemic...
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The crevice corrosion of the Ni/Graphite abradable sealing coating with open porous for engine of aircrafts will happen,when it serves in marine environment.A simulated occluded corrosion cell was used to study chemical changes of Ni/Graphite coating in ***% NaCl solution at 35℃.The corrosion behaviors of Ni in simulated solution was investigated by potentialdynamic polarization test.X-ray diffraction (XRD) was used to study the corrosion *** results showed that as the anodic current passes through the cell,the pH value of occluded solution decreased and the Cl- migrates into the occluded cell,meanwhile the Ni2+ and Na+ migrates out the occluded *** Cl- concentration in the occluded cell increased and Ni(OH)2· XH2O generated outside the occluded *** curves showed that the corrosion potential Ecorr of Ni decreased when the pH decreased and the Cl- enriched.
The objective of this paper is to propose a universal methodology for performance assessment of run-to-run control in semiconductor manufacturing. The slope of the linear semiconductor process model is assumed to be k...
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The objective of this paper is to propose a universal methodology for performance assessment of run-to-run control in semiconductor manufacturing. The slope of the linear semiconductor process model is assumed to be known or subjected to mild plant/model mismatch. Based on an internal model control framework, analytical expressions of minimum variance performance (MVP) and best achievable performance (BAP) for a series of run-to-run control schemes are derived. In the methodology, closed-loop identification is utilised as the first step to estimate the noise dynamics via routine operating data, and numerical optimisation is employed as a second step to calculate the best achievable performance bounds of the run-to-run control loops. The validity of the methodology is justified by examples of performance assessment for EWMA control, double EWMA control and RLS-LT control, even under circumstances where the processes encounter model mismatch, metrology delay and more sophisticated noises. Several essential characteristics of run-to-run control are discovered by performance assessment, and valuable advice is offered to process engineers for improving the run-to-run control performance. Furthermore, a useful application example for online performance monitoring and optimal tuning of run-to-run controller demonstrates the advantage of the methodology.
Since the scalability of logic circuits is becoming larger and more complex, the auto-design is becoming more and more difficult. In order to improve automatic design and performance evaluation of logic circuits in ef...
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Since the scalability of logic circuits is becoming larger and more complex, the auto-design is becoming more and more difficult. In order to improve automatic design and performance evaluation of logic circuits in efficiency and capability of optimization, multiobjective simulated annealing (MSA) based increasable evolution approach is designed to evolve logic circuits automatically with an extended matrix encoding method, which can be able to reflect the potential performance of a circuit and reduce the risk of deleting a circuit with a good developing potential during evolution is devised. In the process of evolution, each individual is renewedly associated to a corresponding objective in terms of a novel adaptive evaluation method at each generation. In experiments, complicated arithmetic circuits are designed to assess the performance of MSA against other algorithms. Results indicate that the proposed method could design logic circuits efficiently.
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