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131.
In a dense urban region in which high-rise buildings are packed inside limited land areas, the daylight components reflected from ground and surrounding buildings play significant roles in daylighting design. The natural light available in an interior strongly depends on the amount of daylight reaching the window facades. Lately we proposed a calculation procedure, presented in form of simple mathematical expressions and diagrams, to determine the daylight illuminance on a vertical plane under overcast skies. This paper extends the study to non-overcast sky conditions. The performance of the proposed method was evaluated by comparison with the daylight illuminance simulated by a lighting software, namely RADIANCE, and with measurements under real skies. It was found that the data estimated by the proposed method were in good agreement both with the values simulated by RADIANCE and with the measured results. The paper offers to architects and building engineers a useful tool for estimating the daylight illuminance and in particular for determining and assessing various daylighting schemes and concepts during design and construction stages. 相似文献
132.
Sandro Carrara Andrea Cavallini Giovanni De Micheli Francesco Valle Bruno Samorì Bruno Riccò Tony Munter 《Microelectronics Journal》2010,41(11):711-717
Label-free DNA detection plays a crucial role in developing point-of-care biochips. Capacitance detection is a promising technology for label-free detection. However, data published in literature often show evident time drift, large standard deviation, scattered data points, and poor reproducibility. To address these problems, mercapto-hexanol or similar alkanethiols are usually considered as blocking agents. The aim of the present paper is to investigate new blocking agents to further improve DNA probe surfaces. Data from AFM, SPR, florescence microscopy, and capacitance measurements are used to investigate new lipoate and ethylene-glycol molecules. The new surfaces offer further improvements in terms of diminished detection errors. Film structures are investigated at the nano-scale to justify the detection improvements in terms of probe surface quality. This study demonstrates the superiority of lipoate and ethylene-glycol molecules as blocking candidates when immobilizing molecular probes onto spot surfaces in label-free DNA biochip. 相似文献
133.
螯合剂的绿色化进展与趋势 总被引:1,自引:1,他引:0
NTA.EDTA和STPP广泛应用于各种洗涤配方中。然而,NTA最近被列为具有潜在致癌性的物质,EDTA的生物降解性差,而STPP则会导致河流、湖泊富营养化。随着人们健康和环保意识逐渐加强以及相应法规日趋严格.这些传统洗涤助剂将逐渐被绿色螯合剂产品所取代。 相似文献
134.
András Tompos József L. Margitfalvi Lajos Végvári Alfred Hagemeyer Tony Volpe C. J. Brooks 《Topics in Catalysis》2010,53(1-2):100-107
This paper reports the combination of Holographic Mapping (HM) and Artificial Neural Networks (ANNs) in order to provide a benchmark visualization of a multi-dimensional space in two-dimensional forms. In this approach each matrix point in HM represents virtual catalytic data generated by means of ANNs in order to visualize the given multi-dimensional experimental space. A 12-dimensional experimental space related to the composition of catalysts designed for the water gas shift reaction (WGSR) from 12 possible components supported on ZrO2 is visualized. Catalytic data obtained in an earlier combinatorial screening process at 300 °C were used for training of the ANNs. The results show that the visualization of large experimental spaces having more than half a million virtual experimental points can be accomplished. The analysis of synergistic effects between different components revealed that the key components of water gas shift catalysts at 300 °C were Pt, Fe, Eu and V, while Co, Ru, Sb, Ge and Mo had a pronounced negative effect on the activity. 相似文献
135.
S. Dorr Brian Ashley Moerke Michael Bur Chuck Bassett Tony Aderman Dan Traynor Russell D. Singleton Peter H. Butchko Jimmy D. Taylor II 《Journal of Great Lakes research》2010
Diverse management techniques have been used to mitigate conflicts between humans and double-crested cormorants (Phalacrocorax auritus) including harassment methods supplemented by lethal take. In this study we evaluated impacts of programs to harass spring migrating cormorants on the walleye (Sander vitreus) fishery in Brevoort Lake and the yellow perch (Perca flavescens) and walleye fisheries at Drummond Island. Cormorant foraging declined significantly (p < 0.05) at both locations subsequent to initiation of harassment programs. Overall harassment deterred 90% of cormorant foraging attempts while taking less than 6% lethally on average at each site. Yellow perch were a predominate prey item in number and biomass at both locations. Walleye made up a small proportion of the diet at both locations. However, both walleye and yellow perch abundance increased significantly (p < 0.05) at Drummond Island. Walleye abundance at age 3 increased to record levels in 2008 following 3 years of cormorant management at Brevoort Lake. The estimated cormorant consumption of age-1 walleye in the absence of management at Brevoort Lake during 2005 would account for 55% of the record 2006 age-1 walleye population. These results support the hypothesis that cormorant predation on spawning aggregations of sportfish was a significant mortality factor and cormorant management reduced sportfish mortality and increased abundance at both locations. Continuation of harassment programs and fishery assessments will determine whether improvement of targeted sport fisheries through control of spring migrating cormorants is sustainable. 相似文献
136.
137.
In modal testing, an impulse is often used to excite the structure and a linear transducer is used to measure the response. For these impact tests, two signals are measured: the impulsive force and the vibration response. Any lack of synchronization in the time domain acquisition of the two signals results in a frequency-dependent phase error in the frequency response function, or FRF. However, knowledge of the time delay may be used to correct the corresponding phase error. In this research, tests were conducted to measure the frequency-dependent phase error for a capacitive sensor and a frequency domain technique is proposed to correct the FRF. The method was validated using an FRF measurement of a cylindrical artifact mounted in a milling machine spindle. 相似文献
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