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991.
The effect on indoor air quality of an air purifier based on photocatalytic oxidation (PCO) was determined by different measuring techniques: sensory assessments of air quality made by human subjects, Proton-Transfer-Reaction Mass Spectrometry (PTR-MS) and chromatographic methods (Gas Chromatography/Mass Spectrometry and High-Pressure Liquid Chromatography with UV detection). The experiment was conducted in a simulated office, ventilated with 0.6 h−1, 2.5 h−1 and 6 h−1, in the presence of additional pollution sources (carpet, chipboard and linoleum). At the lowest air change rate, additional measurements were made with no pollution sources present in the office. All conditions were tested with the photocatalytic air purifier turned on and off. The results show that operation of the air purifier in the presence of pollutants emitted by building materials and furniture improves indoor air quality, as documented by sensory assessments made by human subjects. It also reduces concentrations of many chemical compounds present in the air as documented by the PTR-MS technique. For the lowest ventilation, results from measurements using the chromatographic methods have similar tendency, however many of the 50 compounds that were targeted for analysis were not detected at all, independent of whether the purifier was on or off. For the two conditions with higher ventilation the results were inconclusive. 相似文献
992.
Strategies for the identification of allosteric modulators of chemokine receptors largely rely on various cell‐based functional assays. Radioligand binding assays are typically not available for allosteric binding sites. We synthesized, purified, and applied the first tritium‐labeled allosteric modulator of the human chemokine receptor CXCR3 (RAMX3, [3H]N‐{1‐[3‐(4‐ethoxyphenyl)‐4‐oxo‐3,4‐dihydropyrido[2,3‐d]pyrimidin‐2‐yl]ethyl}‐2‐[4‐fluoro‐3‐(trifluoromethyl)phenyl]‐N‐[(1‐methylpiperidin‐4‐yl)methyl]acetamide). RAMX3 is chemically derived from 8‐azaquinazolinone‐type allosteric modulators and binds to the CXCR3 receptor with a Kd value of 1.08 nM (specific activity: 80.4 Ci mmol?1). Radioligand displacement assays showed potent negative cooperativity between RAMX3 and chemokine CXCL11, providing a basis for the use of RAMX3 to investigate other potential allosteric modulators. Additionally, the synthesis and characterization of a number of other full and truncated 8‐azaquinazoline analogues were used to validate the binding properties of RAMX3. We demonstrate that RAMX3 can be efficiently used to facilitate the discovery and characterization of small molecules as allosteric modulators of the CXCR3 receptor. 相似文献
993.
994.
S Ricci M Liard B Birkhofer D Lootens A Bruhwiler P Tortoli 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2012,59(7):1395-1401
Rheological fluid behavior characterization is crucial for the industrial production of cosmetics, food, pharmaceutics, adhesive, sealants, etc. For example, the measurement of specific rheological features at every step of the production chain is critical for product quality control. Such measurements are often limited to laboratory tests on product specimens because of technical difficulties. In this work, we present an embedded system suitable for in-line rheometric evaluation of highly filled polyurethane-based adhesives. This system includes an ultrasound front-end and a digital signal processing section integrated in a low-cost field-programmable gate array. The system measures the real-time velocity profile developed in the pipe by the fluid, employing a Doppler multigate technique. The high-resolution velocity profile, combined with a pressure drop measurement, allows an accurate evaluation of the flow consistency index, K, and the flow behavior index, n, of the interrogated fluid. 相似文献
995.
Gbabode G Dumont N Quist F Schweicher G Moser A Viville P Lazzaroni R Geerts YH 《Advanced materials (Deerfield Beach, Fla.)》2012,24(5):658-662
A new phase of a known discotic liquid crystal is observed at the interface with a rigid substrate. The structure of the substrate-induced phase has been characterized by atomic force microscopy, specular X-ray diffraction, and small-angle and wide-angle grazing incidence X-ray diffraction. The substrate-induced phase, which has a thickness of ~30 nm and a tetragonal symmetry, differs notably from the bulk phase. The occurrence of such phase casts a new light on alignment of discotic liquid crystals. 相似文献
996.
Unilateral interparticle interactions have an effect on the elastic response of granular materials due to the opening and closing of contacts during quasi-static shear deformations. A simplified model is presented, for which constitutive relations can be derived. For biaxial deformations the elastic behavior in this model involves three independent elastic moduli: bulk, shear, and anisotropy modulus. The bulk and the shear modulus, when scaled by the contact density, are independent of the deformation. However, the magnitude of the anisotropy modulus is proportional to the ratio between shear and volumetric strain. Sufficiently far from the jamming transition, when corrections due to non-affine motion become weak, the theoretical predictions are qualitatively in agreement with simulation results. 相似文献
997.
Abstract: Changes in the mechanical characteristics of the structural steel because of fatigue damage accumulation are investigated in this article. Cyclic loading was performed in a complex stress state. Tubular specimens were loaded by axial force and torque, with loading performed along proportional and non‐proportional paths in the strain space. Material characteristics in the form of the stress–strain curve and yield surface were determined in the ‘as received’ state and after cyclic loading. It was found that accumulation of the fatigue damage because of cyclic loading in a complex stress state along proportional and non‐proportional paths in the strain space is manifested by the increase in inelastic response. The rate of damage was found to be higher for non‐proportional (circular) loading paths than that for proportional loading with the same strain amplitude. 相似文献
998.
Peter J. Gress Per I. Widenborg Sergey Varlamov Armin G. Aberle 《Progress in Photovoltaics: Research and Applications》2010,18(3):221-228
The interconnection of solar cells is a critical part of photovoltaic module fabrication. In this paper, a high‐yield, low‐cost method for interconnecting polycrystalline silicon thin‐film solar cells on glass is presented. The method consists of forming adjacent, electrically isolated groves across the cells using laser scribing, and then forming wire bonds over each laser scribe, resulting in series interconnection of the individual solar cells. Wire bonds are also used to connect the first and last solar cell in the string to external (tabbing) leads, forming a mini‐module. A layer of white paint is then applied, which acts as both an encapsulation layer and an additional back surface reflector. Using this method, an 8·3% efficient mini‐module has been fabricated. By exploiting recent developments in wire bonding technology, it appears that this process can be automated and will be capable of forming solar cell interconnections on large‐area modules within relatively short processing times (∼10 min for a 1 m2 module). Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
999.
Michael Wiegand Manfred Klenner Dietrich Klakow 《Language Resources and Evaluation》2013,47(4):1049-1088
In this article, we examine the effectiveness of bootstrapping supervised machine-learning polarity classifiers with the help of a domain-independent rule-based classifier that relies on a lexical resource, i.e., a polarity lexicon and a set of linguistic rules. The benefit of this method is that though no labeled training data are required, it allows a classifier to capture in-domain knowledge by training a supervised classifier with in-domain features, such as bag of words, on instances labeled by a rule-based classifier. Thus, this approach can be considered as a simple and effective method for domain adaptation. Among the list of components of this approach, we investigate how important the quality of the rule-based classifier is and what features are useful for the supervised classifier. In particular, the former addresses the issue in how far linguistic modeling is relevant for this task. We not only examine how this method performs under more difficult settings in which classes are not balanced and mixed reviews are included in the data set but also compare how this linguistically-driven method relates to state-of-the-art statistical domain adaptation. 相似文献
1000.
Logean X. Dietrich F. Hubaux J.-P. Grisouard S. Etique P.-A. 《Communications Magazine, IEEE》1999,37(7):132-138
We are primarily interested in formal techniques and how they are applied to the development of hybrid services in particular. We analyze the peculiarities of such services, look at the use of formal techniques for communication services in the industry, and highlight some of the major concerns for the application of formality in an industrial environment. It is argued that with the introduction of hybrid services, more pragmatism is required in applying formal techniques. We describe an ongoing joint collaboration of Alcatel, Swisscom, and the Swiss Federal Institute of Technology in which formal techniques are applied to the specification and testing of hybrid services 相似文献