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101.
Yates SR 《Environmental science & technology》2006,40(10):3223-3228
A field experiment was conducted to measure surface dissipation and volatilization of the herbicide triallate after application to bare soil using micrometeorological, chamber, and soil-loss methods. The volatilization rate was measured continuously for 6.5 days and the range in the daily peak values for the integrated horizontal flux method was from 32.4 (day 5) to 235.2 g ha(-1) d(-1) (day 1), for the theoretical profile shape method was from 31.5 to 213.0 g ha(-1) d(-1), and for the flux chamber was from 15.7 to 47.8 g ha(-1) d(-1). Soil samples were taken within 30 min after application and the measured mass of triallate was 8.75 kg ha(-1). The measured triallate mass in the soil at the end of the experiment was approximately 6 kg ha(-1). The triallate dissipation rate, obtained by soil sampling, was approximately 334 g ha(-1) d(-1) (98 g d(-1)) and the average rate of volatilization was 361 g ha(-1) d(-1). Soil sampling at the end of the experiment showed that approximately 31% (0.803 kg/2.56 kg) of the triallate mass was lost from the soil. Significant volatilization of triallate is possible when applied directly to the soil surface without incorporation. 相似文献
102.
TR Rudd E Macchi C Gardini L Muzi M Guerrini EA Yates G Torri 《Analytical chemistry》2012,84(15):6841-6847
Risks of contamination of the major clinical anticoagulant heparin can arise from deliberate adulteration with unnatural or natural polysaccharides, including heparin from other animal sources, other natural products, or artifacts of manufacture, and these can escape detection by conventional means. Currently, there is no generally applicable, objective test recommended by regulators that can detect these in pharmaceutical heparin, and this continues to leave heparin exposed to contamination risks. Two-dimensional correlation spectroscopic-filtering with iterative random sampling (2D-COS-firs) is reported. It employs a difference covariance matrix with iterative random sampling, and is capable of revealing contamination in pharmaceutical heparin to a high level of sensitivity irrespective of the nature of those features. The technique is suitable to any situation in which a comparison of a single entity to a family of heterogeneous entities, particularly natural products and biosimilars, needs to be made, and will find application in pharmaceutical monitoring, manufacturing quality control, materials science, biotechnology, and metabolomic investigations. 相似文献
103.
P. J. de Visser J. J. A. Baselmans P. Diener S. J. C. Yates A. Endo T. M. Klapwijk 《Journal of Low Temperature Physics》2012,167(3-4):335-340
We present measurements of quasiparticle generation-recombination noise in aluminium Microwave Kinetic Inductance Detectors, the fundamental noise source for these detectors. Both the quasiparticle lifetime and the number of quasiparticles can be determined from the noise spectra. The number of quasiparticles saturates to 10?μm?3 at temperatures below 160?mK, which is shown to limit the quasiparticle lifetime to 4?ms. These numbers lead to a generation-recombination noise limited noise equivalent power (NEP) of 1.5×10?19?W/Hz1/2. Since NEP∝N qp , lowering the number of remnant quasiparticles will be crucial to improve the sensitivity of these detectors. We show that the readout power now limits the number of quasiparticles and thereby the sensitivity. 相似文献
104.
Jochem Baselmans Stephen Yates Pascale Diener Pieter de Visser 《Journal of Low Temperature Physics》2012,167(3-4):360-366
The next generation of far infrared radiation detectors is aimed to reach photon noise limited performance in space based observatories such as SPICA and BLISS. These detectors operate at loading powers of the astronomical signal of a few Attowatt (10?18 W) or less, corresponding to a sensitivity expressed in noise equivalent power as low as $\mathrm{NEP} = 2\times10^{-20}\ \mbox{W}/\sqrt{\mathrm{Hz}}$ . We have developed a cryogenic test setup for microwave Kinetic Inductance Detectors (MKIDs) that aims to reach these ultra-low background levels. Stray light is stopped by using a box in a box design with a sample holder inside another closed box. Microwave signals for the MKID readout enters the outer box through custom made coax cable filters. The stray light loading per pixel is estimated to be less than 60×10?18 W during nominal operation, a number limited by the intrinsic sensitivity of the MKIDs used to validate the system. 相似文献
105.
Jiguang LiSunhee Kim Sean EdingtonJoseph Nedy Shinuk Cho Kwanghee Lee Alan J Heeger Mool C. Gupta John T. Yates Jr 《Solar Energy Materials & Solar Cells》2011,95(4):1123-1130
We describe a study of the stabilization behavior of P3HT/PCBM organic solar cells under air and UV irradiation using a 20 nm thin TiOx protection layer made by partial hydrolysis of a Ti-alkoxide and spin coating in air. Data on the degradation of solar cell performance under air and under UV exposure are presented indicating that significant improvements are observed with TiOx layer protection. The protection mechanism has been investigated by transmission IR and UV spectroscopy and by ESR spectroscopy. The results of this study suggest how sol-gel derived TiOx films containing organic functionalities serve as effective passivation films for protection from oxygen when excited by photons, where the photooxidation of the bound organic moieties causes oxygen gas scavenging. 相似文献
106.
Tomatoes (Solanum lycoperiscum) are a popular produce choice and provide many bioactive compounds. Consumer choice of tomatoes is influenced by flavor and visual appearance and external texture cues including hand firmness and sliceability. The objective of this study was to determine drivers of liking for fresh tomatoes across 3 stages of consumption. Seven tomato cultivars were ripened to a 6 on the USDA color chart. Trained panelists documented appearance, flavor, and texture attributes of tomatoes in triplicate. Tomato consumers (n = 177) were provided with knives and cutting boards and evaluated tomatoes across 3 stages: appearance (stage 1), slicing (stage 2), and consumption (stage 3). Consumers evaluated overall liking at each stage. Analysis of variance and external preference mapping were conducted. Overall liking was highest during the appearance portion of the test and lowest during the consumption portion (P < 0.05). Drivers of liking at stage 1 were color intensity, even outside color, and overall aroma. Drivers of liking at stage 2 were wetness/juiciness and overall aroma. Wetness/juiciness, seed presence, ripe flavor, and sweet and umami tastes were drivers of liking for tomatoes at consumption (stage 3). Four separate clusters of tomato consumers were identified. Cluster 1 preferred tomatoes with even color, higher color intensity, and flavor intensity. Cluster 2 preferred firm tomatoes. Cluster 3 preferred tomatoes that were soft and at peak ripeness; this cluster also had the highest liking scores for all tomatoes. Cluster 4 consumers generally consumed tomatoes in sandwiches rather than as‐is and preferred tomatoes with even and intense color. Tomato growers can utilize these results to target cultivars that are well liked by consumers. 相似文献
107.
Marylynn V. Yates 《臭氧:科学与工程》2008,30(1):70-72
Adenoviruses have been shown to be highly resistant to inactivation by ultraviolet (UV) light. While a dose of 40 mJ/cm2 is generally considered sufficient to effect at least a 4-log (99.99%) inactivation of most waterborne pathogens (e.g., hepatitis A virus, Salmonella, Cryptosporidium), recent studies have indicated that doses of 120 mJ/cm2, and possibly up to 200 mJ/cm2 are required to achieve the same level of inactivation of adenoviruses. In order to ensure a high degree of public health protection, the USEPA adopted a UV dose table value of 186 mJ/cm2 for 4-log inactivation credit in the Long-Term 2 Enhanced Surface Water Treatment Rule. This may have a significant effect on the number of systems that are able to utilize UV as the disinfectant, due to the higher costs associated with providing the increased UV dosage. This presentation will provide an introduction to the adenoviruses, including their health effects, routes of transmission, and potential for contamination of water. 相似文献
108.
M.A. Martín-Luengo M. Yates M.J. Martínez Domingo B. Casal M. Iglesias M. Esteban E. Ruiz-Hitzky 《Applied catalysis. B, Environmental》2008,81(3-4):218-224
Highly selective limonene conversions to p-cymene in short reaction times were achieved under “solvent free” conditions over mesoporous silica–alumina supports heated by microwave irradiation. An increase in the silica content of these mixed oxides led to increases in the specific surface area, porosity (pore size and volume) and the surface acidity. The conversion and selectivity of limonene to p-cymene under microwave irradiation was also found to rise as the silica content in these mixed oxides was increased. By careful choice of the solid and reaction parameters the activities for the conversion of limonene and selectivity to p-cymene (used as an intermediate in fine chemical syntheses) could be fine tuned. Results are presented under both dry media and reflux conditions. 相似文献
109.
Aikman D Barrett P Kapadia S King M Proudman J Taylor T de Weymarn I Yates T 《Philosophical transactions. Series A, Mathematical, physical, and engineering sciences》2011,369(1956):4798-4817
Uncertainty is pervasive in economic policy-making. Modern economies share similarities with other complex systems in their unpredictability. But economic systems also differ from those in the natural sciences because outcomes are affected by the state of beliefs of the systems' participants. The dynamics of beliefs and how they interact with economic outcomes can be rich and unpredictable. This paper relates these ideas to the recent crisis, which has reminded us that we need a financial system that is resilient in the face of the unpredictable and extreme. It also highlights how such uncertainty puts a premium on sound communication strategies by policy-makers. This creates challenges in informing others about the uncertainties in the economy, and how policy is set in the face of those uncertainties. We show how the Bank of England tries to deal with some of these challenges in its communications about monetary policy. 相似文献
110.
Hishinuma Earl S.; Andrade Naleen N.; Johnson Ronald C.; McArdle John J.; Miyamoto Robin H.; Nahulu Linda B.; Makini George K. Jr.; Yuen Noelle Y. C.; Nishimura Stephanie T.; McDermott John F. Jr.; Waldron Jane A.; Luke Kenneth N.; Yates Alayne 《Canadian Metallurgical Quarterly》2000,12(2):140
This article reports on the psychometric properties of a newly constructed Hawaiian Culture Scale—Adolescent Version. A total of 2,272 Native Hawaiian and 1,170 non-Hawaiian adolescents were administered this 50-item inventory that measures the source of learning the Hawaiian way of life, how much Hawaiian beliefs are valued and important to maintain, how much non-Hawaiian beliefs are valued, Hawaiian blood quantum, and specific cultural traditions (seven subscales?=?Lifestyles, Customs, Activities, Folklore, Causes—Locations, Causes—Access, and Language Proficiency). The results strongly supported the internal consistency and validity of the measures for both the Hawaiian and non-Hawaiian groups. On the basis of the demographic data, partial support was offered for cross-cultural theories of ethnic identity. More consistent support was found for multiculturalism in Hawai'i's adolescents. Further research is needed to link these measures with indicators of psychological adjustment (e.g., depression, anxiety, substance use). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献