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1.
Mulcahy Nicholas J.; Call Josep; Dunbar Robin I. M. 《Canadian Metallurgical Quarterly》2005,119(1):23
Two important elements in problem solving are the abilities to encode relevant task features and to combine multiple actions to achieve the goal. The authors investigated these 2 elements in a task in which gorillas (Gorilla gorilla) and orangutans (Pongo pygmaeus) had to use a tool to retrieve an out-of-reach reward. Subjects were able to select tools of an appropriate length to reach the reward even when the position of the reward and tools were not simultaneously visible. When presented with tools that were too short to retrieve the reward, subjects were more likely to refuse to use them than when tools were the appropriate length. Subjects were proficient at using tools in sequence to retrieve the reward. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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F Javier Álvarez‐Hornos Carmen Gabaldón Vicente Martínez‐Soria Paula Marzal Josep‐Manuel Penya‐roja 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2008,83(5):643-653
BACKGROUND: Two peat biofilters were used for the removal of toluene from air for one year. One biofilter was fed with pure toluene and the other received 1:1 (by weight) ethyl acetate:toluene mixture. RESULTS: The biofilters were operated under continuous loading: the toluene inlet load (IL) at which 80% removal occurred was 116 g m?3 h?1 at 57 s gas residence time. Maximum elimination capacity of 360 g m?3 h?1 was obtained at an IL of 745 g m?3 h?1. The elimination of toluene was inhibited by the presence of ethyl acetate. Intermittent loading, with pollutants supplied for 16 h/day, 5 days/week, did not significantly affect the removal efficiency (RE). Biomass was fully activated in 2 h after night closures, but 6 h were required to recover RE after weekend closures. Live cell density remained relatively constant over the operational period, while the dead cell fraction increased. Finally, a 15 day starvation period was applied and operation then re‐started. Performance was restored with similar re‐acclimatization period to that after weekend closures, and a reduction in dead cell fraction was observed. CONCLUSION: This study demonstrates the capacity of the system to handle intermittent loading conditions that are common in industrial practices, including long‐term starvation. Copyright © 2008 Society of Chemical Industry 相似文献
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This paper presents a compact model for on-chip decoupling capacitors (decaps) including gate-oxide leakage. The model makes use of only four parameters, namely, channel resistance, gate-oxide capacitance, and two parameters to quantify gate-oxide leakage, to predict the static and dynamic response of decaps. Quality indices have been defined to enable development of decap design guidelines and evaluation of performance of such capacitors. The model shows how the gate leakage and longer channel lengths severely affect the performance of on-chip decaps for both low and high frequencies. The model also shows that lumped models of decaps at high frequencies fail and have to be substituted by a distributed model. Application of the model uncovers tradeoffs for thin- and thick-oxide capacitors in an available 90-nm CMOS technology. For a general-purpose technology, a reference capacitance value has been realized using decaps with a discrete width and length. Our model predicts that thick-oxide n-channel (p-channel) capacitors require /spl sim/3.37x (/spl sim/3.31x) more silicon area and /spl sim/1.70x (/spl sim/1.17x) degraded time response as compared to their thin-oxide versions. The time response is even more degraded (/spl prop/L/sup 2/) when longer channel decaps are used. This paper contributes by defining performance benchmarks for decaps. 相似文献
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Time-scaling properties of the isothermal transformation kinetics have been tested for three Fe-B-based metallic glasses exhibiting two crystallization stages. The time scale was defined as the time at which crystallization has reached half completion and is derived from calorimetric (DSC) data. The temperature dependence of the time-scaling parameter shows a lowtemperature freezing behaviour and can be described by empirical functions based on free-volume considerations. 相似文献
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Athanasios Eftaxias Josep Font Agusti Fortuny Azael Fabregat Frank Stüber 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(6):677-687
The wet air oxidation of phenol over a commercial active carbon catalyst was studied in a trickle bed reactor (TBR) in the temperature and oxygen partial pressure ranges of 120–160 °C and 0.1–0.2 MPa, respectively. The performance of the active carbon was compared in terms of phenol and COD destruction. The weight change of active carbon due to reaction was also measured. Finally, oxic phenol adsorption isotherms were assessed in batch conditions at 25, 125 and 160 °C. In order to use the conversion data obtained from the TBR for a kinetic study, special care was taken to check the kinetic control in the TBR experiments. Several kinetic models including power law or Langmuir–Hinshelwood expressions were considered to describe the catalytic oxidation of phenol over active carbon. The simple power law model with first order dependence on both phenol and oxygen concentration predicted satisfactorily the experimental data not only over the entire range of operating conditions studied, but also outside its validity range. Copyright © 2005 Society of Chemical Industry 相似文献
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Fernández Álvaro Fernández Camino Miguel-Dávila José-Ángel Conde Miguel Á. 《The Journal of supercomputing》2021,77(3):2302-2325
The Journal of Supercomputing - The integration of a Supercomputer in the educational process improves student’s technological skills. The aim of the paper is to study the interaction between... 相似文献
9.
Influence of Mn and Cu addition on the hyperfine parameters of amorphous and nanocrystalline FeCoNbB alloys 总被引:1,自引:0,他引:1
The effects of Cu and Mn addition on the hyperfine field of FeCoNbB HITPERM alloys are discussed from Mössbauer spectrometry. Amorphous and nanocrystalline samples at different stages of the nanocrystallization were studied. The effect of Cu addition correlates with the observed refinement of the microstructure. Mn mainly partitions to the matrix, decreasing the average hyperfine field of the amorphous matrix, although some Mn remains in the nanocrystalline grains, presumably, in a concentration below the maximum solubility of Mn in -Fe. 相似文献
10.
Marta Teixeira Pinto Ana Sofia Ribeiro Inês Conde Rita Carvalho Joana Paredes 《International journal of molecular sciences》2021,22(1)
The high plasticity of cancer stem-like cells (CSCs) allows them to differentiate and proliferate, specifically when xenotransplanted subcutaneously into immunocompromised mice. CSCs are highly tumorigenic, even when inoculated in small numbers. Thus, in vivo limiting dilution assays (LDA) in mice are the current gold standard method to evaluate CSC enrichment and activity. The chick embryo chorioallantoic membrane (CAM) is a low cost, naturally immune-incompetent and reproducible model widely used to evaluate the spontaneous growth of human tumor cells. Here, we established a CAM-LDA assay able to rapidly reproduce tumor specificities—in particular, the ability of the small population of CSCs to form tumors. We used a panel of organotropic metastatic breast cancer cells, which show an enrichment in a stem cell gene signature, enhanced CD44+/CD24−/low cell surface expression and increased mammosphere-forming efficiency (MFE). The size of CAM-xenografted tumors correlate with the number of inoculated cancer cells, following mice xenograft growth pattern. CAM and mice tumors are histologically comparable, displaying both breast CSC markers CD44 and CD49f. Therefore, we propose a new tool for studying CSC prevalence and function—the chick CAM-LDA—a model with easy handling, accessibility, rapid growth and the absence of ethical and regulatory constraints. 相似文献