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101.
Victoria Watson 《The Journal of Architecture》2013,18(1):99-112
This paper looks at two theoretical statements about ‘space’, both of which are grounded in a vitalist philosophy. The first is Henri Lefebvre's formulation of ‘spatial architectonics’, a structure of concepts which he develops in The Production of Space; the second is Mies van der Rohe's intuition of something he termed ‘authentic form’, a means of triggering new experiences and understandings through sensual engagement with space. Since there are other philosophers and other architects whose thinking about space has been influenced by vitalist philosophy, the discussion will begin with an explanation as to why Lefebvre and van der Rohe have been selected for reciprocal examination. 相似文献
102.
Isotopic transient tracer techniques have been employed to study heterogeneous hydroformylation on Rh/SiO2 and Mn–Rh/SiO2. Pulse injection of D2 and
allowed tracing of the deuterium and CO incorporation pathway into the aldehyde product. The d1- and d2-propionaldehyde responses showed a double-peak, or two-hump, response to the D2 pulse, while
showed a single-hump response to the
pulse. Analysis of the product responses to the D2 pulse in CO/H2/C2H4 and CO/H2/C2H4/C2H5CHO suggests that the first hump of the d1- and d2-propionaldehyde responses was due to rapid H/D exchange with adsorbed propionaldehyde via enol intermediates. The decay of the second hump was due to reaction of adsorbed acyl with spillover hydrogen/deuterium. The
response was due to CO insertion followed by acyl hydrogenation. Compartment modeling of the product responses from the
and D2 pulse inputs allowed determination of residence times of adsorbed intermediates, surface coverages of adsorbed intermediates, and the elementary rate constants for acyl hydrogenation and CO insertion. Elementary rate constants for acyl hydrogenation determined from this study were consistent with the value calculated by transition state theory (TST). The addition of Mn promoter to Rh/SiO2 increased coverages of
,
, and
and shifted the rate-limiting step for propionaldehyde formation. Acyl hydrogenation is the rate-limiting step on Rh/SiO2 while CO insertion and acyl hydrogenation are both kinetically significant on Mn–Rh/SiO2. 相似文献
103.
Jeyasankar Alagarmalai David Nestel Daniela Dragushich Ester Nemny-Lavy Leonid Anshelevich Anat Zada Victoria Soroker 《Journal of chemical ecology》2009,35(5):542-551
The Ethiopian fruit fly, Dacus ciliatus, is an oligophagous pest of cucurbit crops, particularly melons, cucumbers, and marrows (summer squash). The present study
aimed to identify host attractants for D. ciliatus and was guided by a behavioral bioassay and an electrophysiological assay. We tested volatile compounds from the fruits of
a host plant, ripe and unripe Galia melon, Cucumis melo var. reticulates. Both sexes were attracted to melon volatiles. Those of ripe melon were preferred. Gas chromatography-electroantennographic
detection analysis of the behaviorally active ripe melon volatiles consistently showed that 14 compounds elicited similar
antennal responses from both sexes. Twelve compounds were identified by gas chromatography-mass spectrometry (GC-MS) using
GC-MS libraries, retention indices (RI), and authentic standards. The electrophysiological activities of the compounds that
were present at sufficient levels for identification, benzyl acetate, hexanyl acetate, (Z)-3-hexenyl acetate, (Z)-3-octenyl acetate, octanyl acetate, (Z)-3-decenyl acetate, and (E)-β-farnesene, were evaluated at six different dosage levels by using electroantennography (EAG). Benzyl and hexanyl acetates
elicited dose responses only in males, while other tested compounds elicited dose responses in both sexes. The strongest responses
were observed for doses between 100 ng and 10 μg. The dose response, in terms of attractiveness to synthetic compounds within
the active range (as determined by EAG), also was evaluated in the behavioral bioassay. Synthetic acetates were attractive
to both sexes when tested individually. Significant attraction was observed when individual compounds were applied in the
bioassay arena at doses of 0.5–1 μg/dispenser. Blends of compounds in equal proportions also were attractive to the insects.
The most attractive blend was a mixture of four or five identified acetates. The addition of an equal proportion of (E)-β-farnesene to this mixture had a deterrent effect. 相似文献
104.
Graesser Arthur C.; Bowers Cheryl; Olde Brent; Pomeroy Victoria 《Canadian Metallurgical Quarterly》1999,91(2):284
One dimension of reading literacy involves the tracking of agents associated with the text. In a literary short story, there is a society of character agents and pragmatic agents. This study investigated the relative salience of different classes of agents in memory. Two experiments measured source memory as an index of agent salience in long-term memory. Patterns of source memory scores supported an invisible third-person narrator hypothesis and an agent amalgamation hypothesis, but not a structural prominence hypothesis: First-person narrator > nonnarrator character > third-person narrator > 0. Statement detection parameters did not significantly differ among the 3 classes of agents, so differences in source memory could not be explained by differences in the content of the speech acts. Source memory scores also could not be explained by surface features of the text, differences among readers, and sophisticated guessing on the basis of a story abstract. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
105.
Chemokines are a superfamily of small cytokine-like molecules which have been described primarily on the basis of their ability to mediate the migration of verious cell types, particularly those of lymphoid origin. The receptors for these molecules are all seven-transmembrane domain G protein-coupled receptors that have historically been excellent targets for small-molecule drugs. This fact, coupled with the advent of large-scale DNA database mining and the recognition that chemokine receptors are also coreceptors for HIV, has driven discovery in this field at a tremendous rate. This process has included not just an expansion of the number of known chemokines and chemokine receptors, but also a greater appreciation for the variety of functions that chemokines are involved in. We review here the molecules that have come from the most recent years of chemokine research as well as many of the new functions that have been ascribed to them. 相似文献
106.
Adaptation of the van Genuchten expression to the effects of temperature and density for compacted bentonites 总被引:2,自引:0,他引:2
Abel Carlos Jacinto María Victoria Villar Roberto Gmez-Espina Alberto Ledesma 《Applied Clay Science》2009,42(3-4):575-582
The main objective of this work is to highlight the influence of variables like temperature and porosity (dry density) on the water retention curve of expansive clays for the analysis of thermo-hydro-mechanical coupled processes (THM problem).The paper presents retention curves of MX-80 bentonite measured under isochoric conditions for different dry densities and temperatures. The influence of dry density on the water retention capacity depends on the suction range, the limiting value being around 30 MPa. For suctions above this threshold value, the retention capacity in terms of water content is higher as the dry density increases, whereas for lower suctions, the lower the dry density the higher the water content for a particular suction. The retention capacity decreases with temperature, more than predicted by the change in interfacial tension of air–water, especially for high temperatures and low suctions.Accordingly, some modifications of the van Genuchten [van Genuchten, M.Th., 1980. A closed-form equation for predicting the hydraulic conductivity of unsaturated soils. Soil Sci. Soc. Am. J., 44, 892–898.] law have been proposed to fit the experimental values. Effects of temperature and porosity on the water retention capacity (other than the traditionally included in the air entry value coefficient) were incorporated through empirical laws that resemble the experimental evidences. By a fitting process, values of the coefficients in those laws were determined for the material used in this work.Finally, several 1D THM simulations using the computer code “CODE_BRIGHT” have been performed in order to analyse the consequences of considering or not temperature and density influences on the water retention curve. 相似文献
107.
Rural tourism: A sustainable alternative 总被引:2,自引:0,他引:2
The aim of this article is to show and share the results of the research we made in order to improve the situation of sustainable interior rural tourism in Spain. We chose our region: Aragon and we studied the case. We had to consider the financial crisis in the hope that our results would contribute to minimize it. We knew beforehand that rural tourism had been less affected than other sectors but still it was important to reach our goal. 相似文献
108.
Sergio Bravo Javier García‐Alonso Gala Martín‐Pozuelo Victoria Gómez Verónica García‐Valverde Inmaculada Navarro‐González María Jesús Periago 《International Journal of Food Science & Technology》2013,48(8):1744-1749
Light red tomatoes were exposed to different doses of ultraviolet C (UV‐C) irradiation (1.0, 3.0 and 12.2 kJ m?2). After treatment, the tomatoes were stored for 2 days at room temperature, and then analysed to determine the effect of irradiation on the main antioxidants, carotenoids and phenolic compounds and the results compared with the control samples. The lycopene content was found to have increased by 14% with respect to the control samples, while β‐carotene decreased. Cis‐isomers from lycopene also increased when the tomatoes were exposed to irradiation for more than 3 h. UV‐C irradiation also had a positive effect on total phenolic compounds; however, the same effect was not observed in the individually analysed phenolic compounds. While chlorogenic and ferulic acids increased in content, naringenin and rutin contents decreased. These results suggest that UV‐C irradiation of tomatoes could improve the beneficial effect of red tomatoes for human health by increasing the levels of certain bioactive compounds; it could also be used to obtain higher content of bioavailability components, such as cis‐isomers from lycopene. 相似文献
109.
110.
Juan Pablo Carrillo Montes María Teresa Cruz y Victoria Irasema Anaya Sosa Teodoro Santiago Pineda 《International Journal of Food Science & Technology》2010,45(6):1270-1276
Quality assessment of red bell pepper dices preserved through batch dehydration introducing tempering cycles were performed in this work. The parameters considered were: the percentages of ascorbic acid and final antioxidant activity retention, as well as the influence of calcium chloride on diffusivity and colour values. Although, a similar final moisture content was reached through different red bell pepper dehydration processes, but the one with tempering cycles had better qualities than those without tempering. Ascorbic acid and final antioxidant activity retention showed higher values and so were colour intensities compared to control samples in all cases. In respect to the effective diffusivity coefficients, there was an increment as the calcium chloride concentration increased. As of the treatments with tempering cycles, the best scheme was 15 min drying time and 30 min tempering time at 60 °C. 相似文献