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41.
High-temperature co-electrolysis shows comparable performance to steam electrolysis. Current densities above 1 A cm−2 can be reached between 700 °C and 800 °C. Tailor-made syngas is produced, mainly determined by the reactant ratio. The experimental results are supported by modeling. Durability tests with cathode-supported cells show increased voltage degradation rates during electrolysis compared to fuel cell operation. Nickel depletion is found to be the main cause.  相似文献   
42.
Lucy Bullivant looks at the shape of the new office to come. With the onset of increasingly sophisticated communications devices, how is the organisation of space in our immediate working environments going to change? Will the lines between furniture and dynamic electronic devices simply blur? Will the structure of commercial office buildings themselves be required to become increasingly reflexive to meet environmental demands in the face of dwindling energy reserves? Or is the mobile nature of electronic communications actually in danger of rendering the permanent office as we know it extinct? Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
43.
境外建筑师事务所如何适应当前国内的建筑潮流并在其中有所作为?除了在方案竞赛中能展现具有“视觉震撼性”的透视效果图外,还要具备一套行之有效的设计管理系统。主要包括三方面内容:1.团队精神,2.各专业之间的协调,3.阶段性设计质量的保证。文章将就这三个内容展开讨论。  相似文献   
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Magnetic nanoparticles (MNPs) are of high significance in sensing as they provide viable solutions to the enduring challenges related to lower detection limits and nonspecific effects. The rapid expansion in the applications of MNPs creates a need to overview the current state of the field of MNPs for sensing applications. In this review, the trends and concepts in the literature are critically appraised in terms of the opportunities and limitations of MNPs used for the most advanced sensing applications. The latest progress in MNP sensor technologies is overviewed with a focus on MNP structures and properties, as well as the strategies of incorporating these MNPs into devices. By looking at recent synthetic advancements, and the key challenges that face nanoparticle‐based sensors, this review aims to outline how to design, synthesize, and use MNPs to make the most effective and sensitive sensors.  相似文献   
46.
The Cognitively-Based Rapid Assessment Methodology (C-RAM) system manages multiple-user interactions as users work with multiple information sources. Further, it allows users to view, exchange, organize, and combine the information available and it facilitates group decision-making. Three-member teams, randomly assigned in either the (a) view others’ whiteboards or (b) cannot view others’ whiteboards conditions, completed an intelligence analysis and mission planning task. Each team member was given access to a virtual whiteboard populated with decision cards (DCards) containing intelligence information constrained to a specific area of expertise. DCards can be assessed (rated) for decision impact and importance and team members have access to all DCards regardless of experimental condition. Team members who can view their teammates’ whiteboards during collaborative activities achieve significantly higher performance. When compared to teams unable to view others’ whiteboards, they move their own DCards less frequently, add fewer additional DCards to their own whiteboards, and rate others’ DCards less frequently. Additionally, rating one’s own DCards is the only process positively related team performance.  相似文献   
47.
Thirty samples of Pu-Erh tea (a microbial fermented Chinese tea) were collected and assayed for cholesterol synthesis inhibitory activity and polyphenol composition. All samples were able to inhibit the cholesterol biosynthesis in Hep G2 cell model and the inhibition ratios ranged from 7% to 35%. The inhibition abilities of tea polyphenol standards were in the order of gallocatechin gallate (GCG) > epigallocatechin gallate (EGCG) > epicatechin gallate (ECG) > gallic acid > epigallocatechin (EGC) > myricetin > quercetin > catechin (C) > epicatechin (EC). It appears that catechins with a galloyl structure on the B ring or a gallic acid moiety in the structure would have better inhibitory activity. In summary, tea polyphenol may play a role on the cholesterol biosynthesis inhibitory ability of Pu-Erh tea.  相似文献   
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The characteristics and growth mechanisms of fluidized bed granules are dependent both on process variables and the grades of PVP binders used. Generally, an increase in the concentration, spraying rate and volume of binder solution caused an increase in granule size and a decrease in size distribution. These two factors will in turn affect the poured and tapped densities of granules. Granules prepared with PVP K90 solution appeared to grow by primary and secondary agglomeration to give an aggregate structure. Granules prepared with PVP K120 solution were formed through snowballing as the primary agglomeration process. This occurred at low binder solution concentration with secondary agglomeration taking place when the concentration of PVP K120 solution was increased.  相似文献   
50.
The results of an investigation on the Er doping of porous silicon are presented. Electrochemical impedance spectroscopy, optical reflectivity, and spatially resolved energy dispersive spectroscopy (EDS) coupled to scanning electron microscopy measurements were used to investigate on the transient during the first stages of constant current Er doping. Depending on the applied current intensity, the voltage transient displays two very different behaviors, signature of two different chemical processes. The measurements show that, for equal transferred charge and identical porous silicon (PSi) layers, the applied current intensity also influences the final Er content. An interpretative model is proposed in order to describe the two distinct chemical processes. The results can be useful for a better control over the doping process.

PACS

81.05.Rm; 82.45.Rr  相似文献   
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