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In this paper,a non-thermal atmospheric pressure plasma jet at high streaming velocity operating with ambient air is highlighted.In the present technological approach,the employment of air poses a significant challenge.The high oxygen concentration in air results in a reduced concentration of reactive species in combination with a short species lifetime.The plasma jet assembly presented here contains a special dielectric barrier with a high secondary emission coefficient.In this way,the electron density and in turn the density of reactive species is increased.In addition,the plasma jet assembly is equipped with a short electrode.This leads to a higher voltage across the discharge gap and in turn to an increased density of reactive plasma species.The plasma jet is formed within and emitted by a small conical nozzle.A high-speed gas flow with gas velocity of 340 m/s was achieved at the end of the nozzle.In the jet the concentration of toxic and unwanted neutral plasma species like O_3 or NO_x is significantly reduced because of the shorter residence time within the plasma.The range of short-lived active plasma species is in turn considerably enhanced.The jet efficiency and action range measured through the oxidation of a test surface were determined by measuring the increase of surface tension of a polypropylene substrate via contact angle measurements after plasma treatment.Numerical modeling of the plasma plume indicates that oxygen atoms are in fact the main active species in the plasma plume.  相似文献   
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Decision science methods can be effective tools for enhancing organizational participation during strategic and complex decision processes. This involvement promotes development of group consensus for issues as difficult as relating organizational goals and the best methods to achieve them. In an academic context, such a process supports and enhances collegial participation. This paper describes an application of Quality Function Deployment (QFD) decision model to prioritize both courses and course content based on degree of impact on program objectives. The model was developed to quantify curricular decisions involved in restructuring a Masters of Engineering Management degree program. QFD supports selection of the courses and the curricular content that has the highest impact on program goals. The model provides a practical and quantitative methodology for developing faculty consensus in the selection of curricular topics based on a strategic program focus.  相似文献   
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<正>用一个醒目的外罩将一组低能耗的多功能建筑遮蔽起来,从而形成可调控的微气候环境,使建筑群免受风雨侵扰。不管起源于何种情境,"北京芳草地"激进的环境策略和建筑成就都会吸引全球的注意力。更引人注目的是,这是一处纯私人物业,由中国开发商投资、持有并运营,并由来自香港的华人建筑师进行设计。它的构思与建造,恰好与2008年奥运会场地同期。"芳草地"的故事,既有关于奥运给这座首都带来的冲击,和伴随  相似文献   
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Ozone vertical profiles derived from Umkehr observations by the Dobson spectrophotometer at Belsk (52.50° N, 20.47° E) and from ozone soundings carried out at the nearest aerological station, Legionowo (52.24° N, 20.58° E), have been compared with those measured by the MLS instrument on board the Aura spacecraft during the sites' overpasses for the period 2004–2005. It is assumed that the satellite station distance should be less than 2° and less than 4° for the latitudinal and longitudinal difference, respectively. The bias, RMS error, and the correlation coefficients between the ozone content in the Umkehr layers have been calculated using Dobson/sonde/MLS data. The ozone mixing ratio at selected levels in the lower and mid‐stratosphere (from 215 hPa up to 6.8 hPa) have been compared using the sonde/MLS data. The number of analysed daily values was ~40 (Dobson/MLS), 60 (sonde/MLS), and 60 (Dobson/sonde) since August 2004. The comparisons show a good correspondence (bias ~±5%, RMS <10%, correlation coefficient >0.5) between the ozone content in Umkehr layers 4–8 and ozone mixing ratio at pressures <50 hPa. At lower stratosphere (Umkehr layer 3) and upper stratosphere (Umkehr layer 9), there is also statistically significant relationship between the data, but the biases and RMS are ~2 times larger, while the correlation coefficients are still high (>0.7).  相似文献   
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SS RESPONDED IN ACCORDANCE WITH THE APPARENT DISTANCE OF A TARGET, ALTERNATING BETWEEN NORMAL VISION AND MINIFICATION. CHANGES IN PERFORMANCE INDUCED BY CHANGING THE VISUAL CONDITION WERE AS MARKED AFTER REPEATED EXPOSURES AS INITIALLY, PROVIDED THAT NO CURRENT FEEDBACK WAS SUPPLIED. THIS WAS TAKEN AS LACK OF SUPPORT FOR TAYLOR'S PREDICTION: THAT EFFECTS AND AFTEREFFECTS SHOULD DECLINE WITH ALTERNATION OF VISUAL CONDITIONS. CONTRARY TO THE DIFFERENTIAL CONDITIONING MODEL OF ADAPTATION, THEIR ELIMINATION APPARENTLY CONTINUES TO DEPEND ON RESPONSE-PRODUCED FEEDBACK. (FRENCH SUMMARY) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Focal adhesions and podosomes are integrin‐mediated cell‐substratum contacts that can be visualized using interference reflection microscopy (IRM). Here, we have developed automated image‐processing procedures to quantify adhesion turnover from IRM images of live cells. Using time sequences of images, we produce adhesion maps that reveal the spatial changes of adhesions and contain additional information on the time sequence of these changes. Such maps were used to characterize focal adhesion dynamics in mouse embryo fibroblasts lacking one or both alleles of the vinculin gene. Loss of vinculin expression resulted in increased assembly, disassembly and/or in increased translocation of focal adhesions, suggesting that vinculin is important for stabilizing focal adhesions. This method is also useful for studying the rapid dynamics of podosomes as observed in primary mouse dendritic cells.  相似文献   
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A method is described for the analysis of tyramine in meat and meat products by sand column extraction eluted with ethyl acetate. Tyramine is determined quantitatively by fluorometry once the corresponding fluorophore has been formed by reacting the final extract with α-nitrous-β-naphthol Qualitative confirmation is carried out by spectrofluorometry and thin-layer chromatography. The average recovery was 88.80% and the relative standard deviation 6.35%. The method has been applied to 15 Spanish meat products, the amounts found oscillating between 0.13 and 301.2  相似文献   
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SUMMARY: A number of experiments studied growth of weanling rats and urinary nitrogen excretion in young adult rats when cow's milk protein was partially replaced by varying levels supplementary nitrogen. A mixture of nonessential L-amino acids (NEAA) or a mixture of diammoniumcitrate and glycine (DAC-Gly) was used as the source of nitrogen. Substitution of the 15% milk protein diet to the extent of 10% slightly reduced growth; significant growth reduction occurred with substitutions of 20% and greater. Fortification of the diets containing 10.5% milk protein and the supplementary nitrogen sources with sulfur amino acids did not restore growth the maximum rate obtained with the 15% milk protein diet. Additional supplementation with tryptophan further improved growth slightly but not to the maximum rate. Several other essential amino acids, alone or in combination, had no apparent effect. Based on urinary nitrogen excretion, comparable results were obtained with young adult rats by substituting nitrogen for milk protein the diets. The reduced performance following substitution of milk protein with supplementary nitrogen may be due partly to decreased utilization of sulfur amino acids and possibly to decreased utilization of all essential amino acids.  相似文献   
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