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51.
The generation of sets of low‐energy conformations for a given molecule is a central task in drug design. Herein we present a new conformation generator called CONFECT that builds on our previously published library of torsion patterns. Conformations are generated as well as ranked by means of normalized frequency distributions derived from the Cambridge Structural Database (CSD). Following an incremental construction approach, conformations are selected from a systematic enumeration within energetic boundaries. The new tool is benchmarked in several different ways, indicating that it allows the efficient generation of high‐quality conformation ensembles. These ensembles are smaller than those produced by state‐of‐the‐art tools, yet they effectively cover conformational space.  相似文献   
52.
BACKGROUND: Taking into account several requirements for the determination of raffinose family oligosaccharides (RFOs) from Lupinus seeds—e.g., conducting plant breeding projects or food product development—a reasonable combination of efficient automated sample preparation and reliable analysis need to be developed and validated. RESULTS: In this regard pressurized liquid extraction was applied to extract the RFOs from ground and defatted lupin flour. Compared to many other publications, no further pretreatment, such as protein precipitation, was necessary to obtain satisfactory results applying ion chromatography with pulsed amperometric detection. The oligosaccharide content for the examined Lupinus albus samples were in the range 5.19–9.25 g kg−1 and for Lupinus angustifolius RFOs 3.49–4.75 g kg−1. Stachyose has always been the main component followed by raffinose and verbascose. CONCLUSION: The developed sample preparation and analytical method is suited to quantify raffinose, stachyose, verbascose and the disaccharide sucrose and, owing to a high degree of automation for sample preparation and relatively short analysis times by pretty peak separation, particularly high sample numbers can be accomplished. Copyright © 2008 Society of Chemical Industry  相似文献   
53.

This paper presents a general framework for the work system compatibility (WSC) theory based on two fundamental premises: (1) the synergistic effects of the entire domain of work factors upon the performance of individuals in the workplace must be considered; and (2) the work system elements must be balanced to achieve simultaneous optimization of all facets of workplace human performance measures. The WSC theory is integrative on two levels. First, the WSC theory integrates previous human performance theories that only considered the impact of some sub-sets of work factors on selected outcome measures. Secondly, the WSC theory serves to integrate prior theories towards a multi-disciplinary systems approach to work system improvements. The WSC theory provides a methodology for achieving a balance among key elements of work system by simultaneous optimization of the relevant human performance measures.  相似文献   
54.
The impact of the ground line position on the line parameters of signal interconnects built in a 110-nm CMOS technology is investigated in the presence of a conductive substrate. Characteristic line parameters obtained from simulations are validated with two-port network analyzer measurements of specially designed test structures in a frequency range up to 50 GHz. In addition, the influence of the ground line position on time-domain signals in product-related bus systems is explored. It is shown that the impact of substrate effects on the line parameters, and consequently on the signal shape in the time domain, strongly depends on the relative position of the ground line with respect to the signal lines and, as expected, on the length of the line system. The authors show that for short on-chip bus systems (shorter than 2 mm), the influence of the ground line positioning on time-domain signals is negligible. However, for long bus systems (e.g., 5 mm), this influence becomes significant and can no longer be neglected.  相似文献   
55.
Thermostructural composites (TSC) improvement is one of the key factors to ensure future competitiveness of aeronautical and space engines. The TSC technology developed in Snecma Propulsion Solide is based on continuous fiber-reinforced composites and carbon or ceramics matrices deposited by chemical vapor infiltration. This article presents a status of the latest improvements for cost savings of composite reinforcements (so-called texture) and specific matrices developed to increase both durability and temperature capability of previous ceramic composites, operating in oxidative environments.  相似文献   
56.
This study reports the preparation of 1‐amino‐1,2,3‐triazole‐3‐oxide (DPX2) and its transformation to 1,2,3,4‐tetrazine‐1‐oxide. DPX‐2 provides insight into a novel N‐oxide/N‐amino high‐nitrogen system, being the first energetic material in this class. The ability of this material to undergo a nitrene insertion forming 1,2,3,4‐tetrazine‐1‐oxide was also studied, and evidence for this material, the first non‐benzoannulated 1,2,3,4‐tetrazine‐1‐oxide, is presented. The existence of both of these materials opens new strategies in energetic materials design. DPX2 was characterized chemically (Infrared, Raman, NMR, X‐ray) and as a high explosive in terms of energetic performances (detonation velocity, pressure, etc.) and sensitivities (impact, friction, electrostatic). DPX‐2 was found to possess good thermal stability and moderate sensitivities, indicating the viability of N‐amino N‐oxides as a strategy for the preparation of new energetic materials.  相似文献   
57.
A QoS architecture for quantitative service differentiation   总被引:1,自引:0,他引:1  
For the past decade, a lot of Internet research has been devoted to providing different levels of service to applications. Initial proposals for service differentiation provided strong service guarantees, with strict per-flow bounds on delays, loss rates, and throughput, but required high overhead in terms of computational complexity and memory, both of which raise scalability concerns. Recently, the interest has shifted to class-based service architectures with low overhead. However, these newer service architectures only provide weak service guarantees, which do not always address the needs of applications. In this article we introduce a service architecture that supports strong per-class service guarantees, can be implemented with low computational complexity, and only requires maintenance of a little state information. A key mechanism of the proposed service architecture is that service rate allocation to classes is adaptive, and combined with buffer management. Furthermore, instead of using admission control or traffic policing, the proposed architecture exploits explicit congestion notification for the purpose of regulating the traffic entering the network.  相似文献   
58.
International Journal on Digital Libraries - Indexing documents with controlled vocabularies enables a wealth of semantic applications for digital libraries. Due to the rapid growth of scientific...  相似文献   
59.
An experimental study to assess the accuracy of a wire‐mesh sensor with a temporal and spatial resolution of 5 kHz and 4.8 mm in dependence of bubble size has been carried out. As a reference, single air bubbles with a defined bubble size of 2 – 12 mm are injected in a stagnant liquid phase. The results show a higher uncertainty for bubble diameters below the grid resolution of the sensor. In this case, the bubble size depends strongly on the local bubble position within the mesh grid during its passage.  相似文献   
60.
In diesem Beitrag werden Nomogramme für die Bemessung von Stahlbetonkonsolen vorgestellt. Basierend auf den entsprechenden Bemessungsmodellen kann für eine gegebene Stahlbetonkonsole und eine Beanspruchung die Bewehrungsmenge des Zuggurts bestimmt werden. In den Nomogrammen sind alle relevanten Anwendungsgrenzen eingearbeitet. Die Praxistauglichkeit der Nomogramme wird anhand eines Beispiels erläutert. Support for the analysis by concrete brackets. In this contribution nomograms are introduced for the structural analysis of concrete brackets. Based on the appropriate design codes the reinforcement for the tension strut can be determined. In these nomograms all relevant limitations are incorporated. The application of the nomograms is shown using an example.  相似文献   
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