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941.
The trans-lycopene content of fresh tomato homogenates was assessed by means of the laser photoacoustic spectroscopy, the laser optothermal window, micro-Raman spectroscopy, and colorimetry; none of these methods require the extraction from the product matrix prior to the analysis. The wet chemistry method (high-performance liquid chromatography) was used as the absolute quantitative method. Analytical figures of merit for all methods were compared statistically; best linear correlation was achieved for the chromaticity index a* and chroma C*.  相似文献   
942.

Background, aim and scope  

Although life cycle assessment is frequently used in scientific studies of product comparison, many practitioners are looking for improvements in the normalisation, grouping and weighting of life cycle inventory results. Local conditions, which are well known to local experts, are very important to these steps. The goal of this work was to develop a computer-based decision support system for classifying wood products according to their influence on the environment in their whole life cycle. The model specifically addresses local conditions in the Republic of Slovenia and was developed by Slovenian experts.  相似文献   
943.
944.

Background, aim, and scope  

When the service life (or primary life) of built concrete infrastructure has elapsed, a common practice is that the demolished concrete is crushed and recycled, then incorporated into new construction. LCA studies of CO2 emissions focus on the manufacturing and construction and occupancy/utilization phases, without consideration of the demolition and application of recycled concrete into a secondary construction application. Concrete has a documented ability to chemically react with airborne carbon dioxide (CO2); however, carbon capture (or carbonation) by concrete during the primary and secondary life, is not considered in LCA models. This paper incorporates CO2 capture during both primary and secondary life into an LCA model for built concrete.  相似文献   
945.

Background, aim, and scope  

Propagation of parametric uncertainty in life cycle inventory (LCI) models is usually performed based on probabilistic Monte Carlo techniques. However, alternative approaches using interval or fuzzy numbers have been proposed based on the argument that these provide a better reflection of epistemological uncertainties inherent in some process data. Recent progress has been made to integrate fuzzy arithmetic into matrix-based LCI using decomposition into α-cut intervals. However, the proposed technique implicitly assumes that the lower bounds of the technology matrix elements give the highest inventory results, and vice versa, without providing rigorous proof.  相似文献   
946.
947.
948.
This article addresses the semiotic problem of how meaning is agentially grounded: how actual meaning is possible and is justifiably supported by agents’ capabilities and purposes. This article is particularly focused on human agential grounding; however, to a great degree, insights presented here can be extended to other living beings. Specifically, agential meaning is examined here inside the framework of agentive semiotics and embodied, situated and enactive cognition theories, in line with the mind-life continuity general thesis (which intends to naturalize mind and experience). To offer clarity and methodological precision about agential grounding, three explanation categories (called recurrences) are proposed: phylogenetic recurrence, the evolutionary basis for corporal/embodied grounding; ontogenetic recurrence, the developmental basis for individual meaning grounding; and collective recurrence, the basis for meaning recognized, attributed and assigned inside social contexts. These recurrences are conceived as three types of general processes that constantly enclose possibilities for purpose and meaning emergence in humans. As a result of these types of recurrences, two categories of human agendas or purposes are also proposed: individual and collective. Finally, remarks about how these categories can be useful for semiotic analysis and further research are suggested.  相似文献   
949.
In this research, we studied the relationship between the molecular structure of (R)-12-hydroxyoctadecanamide, (R)-N-propyl-12-hydroxyoctadecanamide, and (R)-N-octadecyl-12-hydroxyoctadecanamide and the thermo-mechanical properties of their 2% (wt/wt) organogels developed using safflower oil high in oleic acid (HOSFO) as the liquid phase. Candelilla wax (CW), a well-known edible gelling additive whose main component is hentriacontane, also was studied for comparative purposes. The results obtained show that the attractive interactions (i.e., hydrogen bonding and dipolar interactions) between amide groups and between hydroxyl groups present in the amides resulted in organogels with higher melting temperature, heat of melting, and crystallization parameters than those found in the CW organogel. The rheological parameters associated to the strength of the amide or CW-based gels developed in HOSFO (i.e., yield stress and elastic modulus) seem to be associated with the nature of amide groups (i.e., primary or secondary amide) and the increase in the length of the self-assembly molecular unit (i.e., L value determined by X-ray diffraction) and therefore to the extent of London dispersion forces along the hydrocarbon chain. The creep and recovery measurements allowed an evaluation among the internal structures of the different organogels and demonstrated that independent of the hydrogen bonding and dipolar interaction provided by the amide and the hydroxyl groups, the increase in the hydrocarbon chain length results in higher organogel resistance to deformation and higher instant recovery capacity. However, the stabilization of the self-assembly unit through polar groups (i.e., –CONH2 in HOA) reduces organogel elasticity but provides a higher extended recovery capacity. The results reported in this investigation showed some relationships between gelator structure and the thermo-mechanical properties of low-molecular-mass organic gelator amides. Our long-term objective is to understand the organogelation process to eventually develop trans-free vegetable oil-based food products with novel textures for the consumers.  相似文献   
950.
Documenting local space use of birds that move rapidly, but are too small to carry GPS tags, such as swallows and swifts, can be challenging. For these species, tracking methods such as manual radio‐telemetry and visual observation are either inadequate or labor‐ and time‐intensive. Another option is use of an automated telemetry system, but equipment for such systems can be costly when many receivers are used. Our objective, therefore, was to determine if an automated radio‐telemetry system, consisting of just two receivers, could provide an alternative to manual tracking for gathering data on local space use of six individuals of three species of aerial insectivores, including one Cliff Swallow (Petrochelidon pyrrhonota), one Eastern Phoebe (Sayornis phoebe), and four Barn Swallows (Hirundo rustica). We established automated radio‐telemetry systems at three sites near the city of Peterborough in eastern Ontario, Canada, from May to August 2015. We evaluated the location error of our two‐receiver system using data from moving and stationary test transmitters at known locations, and used telemetry data from the aerial insectivores as a test of the system's ability to track rapidly moving birds under field conditions. Median location error was ~250 m for automated telemetry test locations after filtering. More than 90% of estimated locations had large location errors and were removed from analysis, including all locations > 1 km from receiver stations. Our automated telemetry receivers recorded 17,634 detections of the six radio‐tagged birds. However, filtering removed an average of 89% of bird location estimates, leaving only the Cliff Swallow with enough locations for analysis of space use. Our results demonstrate that a minimal automated radio‐telemetry system can be used to assess local space use by small, highly mobile birds, but the resolution of the data collected using only two receiver stations was coarse and had a limited range. To improve both location accuracy and increase the percentage of usable location estimates collected, we suggest that, in future studies, investigators use receivers that simultaneously record signals detected by all antennas, and use of a minimum of three receiver stations with more antennas at each station.  相似文献   
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