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31.
Richard H. Harris Vicki J. Boyd Graham J. Hutchings Stuart H. Taylor 《Catalysis Letters》2002,78(1-4):369-372
The effect of water addition on the complete oxidation of benzene and propane VOCs by uranium oxide catalysts has been investigated. Benzene oxidation was studied using a silica supported U3O8 catalyst. Complete oxidation is promoted by the addition of 2.6% water compared with the reactivity when no water is added to the reactant feed. Increasing the water concentration to 12.1% resulted in a suppression of oxidation activity. Investigation of propane oxidation using U3O8 shows a dramatic promotion of activity. Propane conversion was ca. 50% at 600 °C without added water, whilst it increased to 100% at 400 °C with the addition of 2.6% water. A comparison of oxidation activity has been made with Mn2O3, an oxide recognised for complete oxidation. In contrast to the U3O8 catalysts the addition of 2.6% water suppresses the activity of Mn2O3. In situ powder X-ray diffraction studies showed that the bulk U3O8 structure was stable under all the reaction conditions. The origin of the increased activity is not clear but may be due to modification of the catalyst surface and the contribution from new reaction pathways such as steam reforming. 相似文献
32.
Rogers Jeffrey M. Jensen Jenny Valderrama Joaquin T. Johnstone Stuart J. Wilson Peter H. 《Virtual Reality》2021,25(2):357-366
Virtual Reality - Stroke rehabilitation suffers from low levels of patient engagement, impeding recovery. Virtual rehabilitation (VR) approaches can improve patient outcomes; however, there is... 相似文献
33.
Stuart Moran Nils Jäger Holger Schnädelbach Kevin Glover 《Personal and Ubiquitous Computing》2016,20(2):261-275
Both breathing and internal self-awareness are an integral part of any yoga practice. We describe and discuss the development of ExoPranayama, an actuated environment that physically manifests users’ breathing in yoga. Through a series of trials with yoga practitioners and expert teachers, we explore its role in the practice of yoga. Our interview results reveal that biofeedback through the environment supported teaching and improved self-awareness, but it impacted group cohesion. Two practical uses of the technology emerged for supporting breath control in yoga: (1) biofeedback can provide new information about users’ current internal states; (2) machine-driven feedback provides users with a future state or goal and leads to improved cohesiveness. 相似文献
34.
Stuart Nolan 《Digital Creativity》2013,24(3):185-192
Abstract This paper reports on 12 participatory design workshops involving 216 young people, aged 9 to 16. It discusses responses to existing and proposed locative and pervasive media technologies in gaming, mapping, gifting, game design, bodystorming, and collaborative storytelling activities. Issues of the technomagical in scenario planning are discussed. 相似文献
35.
Understanding, monitoring and modelling attributes of seagrass biodiversity, such as species composition, richness, abundance, spatial patterns, and disturbance dynamics, requires spatial information. This work assessed the accuracy of commonly available airborne hyper-spectral and satellite multi-spectral image data sets for mapping seagrass species composition, horizontal horizontal-projected foliage cover and above-ground dry-weight biomass. The work was carried out on the Eastern Banks in Moreton Bay, Australia, an area of shallow and clear coastal waters, containing a range of seagrass species, cover and biomass levels. Two types of satellite image data were used: Quickbird-2 multi-spectral and Landsat-5 Thematic Mapper multi-spectral. Airborne hyper-spectral image data were acquired from a CASI-2 sensor using a pixel size of 4.0 m. The mapping was constrained to depths shallower than 3.0 m, based on past modelling of the separability of seagrass reflectance signatures at increasing water depths. Our results demonstrated that mapping of seagrass cover, species and biomass to high accuracy levels (> 80%) was not possible across all image types. For each parameter mapped, airborne hyper-spectral data produced the highest overall accuracies (46%), followed by Quickbird-2 and then Landsat-5 Thematic Mapper. The low accuracy levels were attributed to the mapping methods and difficulties in matching locations on image and field data sets. Accurate mapping of seagrass cover, species composition and biomass, using simple approaches, requires further work using high-spatial resolution (< 5 m) and/or hyper-spectral image data. Further work is required to determine if and how the seagrass maps produced in this work are suitable for measuring attributes of seagrass biodiversity, and using these data for modelling floral and fauna biodiversity properties of seagrass environments, and for scaling-up seagrass ecosystem models. 相似文献
36.
We examine the effect of information sharing within small world networks. Agents receive a signal correlated with the state
of the world (SoW) which is adjusted following discussions with neighbours. If one agent in the network, referred to as an
expert, does not engage in social learning (that is they always follow their own signal) then all agents learn the SoW. It
is found that volatility in the mean level of expectations varies with changes in the number of experts and the network structure.
A trade-off emerges between the level of volatility and the speed at which agents learn of changes to the SoW. A second finding
is that certain network structures lead to information cascades.
相似文献
37.
Nicholas P. Webb Hamish A. McGowan Stuart R. Phinn John F. Leys Grant H. McTainsh 《Environmental Modelling & Software》2009,24(2):214-227
This paper describes the development and validation of the Australian Land Erodibility Model (AUSLEM), designed to predict land susceptibility to wind erosion in western Queensland, Australia. The model operates at a 5 × 5 km spatial resolution on a daily time-step with inputs of grass and tree cover, soil moisture, soil texture and surficial stone cover. The system was implemented to predict land erodibility, i.e. susceptibility to wind erosion, for the period 1980–1990. Model performance was evaluated using cross-correlation analyses to compare trajectories of mean annual land erodibility at selected locations with trends in wind speed and observational records of dust events and a Dust Storm Index (DSI). The validation was conducted at four spatial length scales from 25 to 150 km using windows to represent potential dust source areas centered on and positioned around eight meteorological stations within the study area. The predicted land erodibility had strong correlations with dust-event frequencies at half of the stations. Poor correlations at the other stations were linked to the inability of the model to account for temporal changes in soil erodibility, and comparing trends in the land erodibility of regions with dust events whose source areas lie outside the regions of interest. The model agreement with dust-event frequency trends was found to vary across spatial scales and was highly dependent on land type characteristics around the stations and on the types of dust events used for validation. 相似文献
38.
Identifying and integrating patient and caregiver perspectives for clinical practice guidelines on the screening and management of infectious microorganisms in hemodialysis units 下载免费PDF全文
Hilary M. Miller Allison Tong David J. Tunnicliffe Denise Campbell Jule Pinter Robert J. Commons Eugene Athan Jonathan C. Craig Nicole Gilroy Julianne Green Belinda Henderson Martin Howell Rhonda L. Stuart Carolyn van Eps Muh Geot Wong Janak de Zoysa Meg J. Jardine 《Hemodialysis international. International Symposium on Home Hemodialysis》2017,21(2):213-223
39.
How effectively synaptic and regenerative potentials propagate within neurons depends critically on the membrane properties and intracellular resistivity of the dendritic tree. These properties therefore are important determinants of neuronal function. Here we use simultaneous whole-cell patch-pipette recordings from the soma and apical dendrite of neocortical layer 5 pyramidal neurons to directly measure voltage attenuation in cortical neurons. When combined with morphologically realistic compartmental models of the same cells, the data suggest that the intracellular resistivity of neocortical pyramidal neurons is relatively low ( approximately 70 to 100 Omegacm), but that voltage attenuation is substantial because of nonuniformly distributed resting conductances present at a higher density in the distal apical dendrites. These conductances, which were largely blocked by bath application of CsCl (5 mM), significantly increased steady-state voltage attenuation and decreased EPSP integral and peak in a manner that depended on the location of the synapse. Together these findings suggest that nonuniformly distributed Cs-sensitive and -insensitive resting conductances generate a "leaky" apical dendrite, which differentially influences the integration of spatially segregated synaptic inputs. 相似文献
40.
Vladimir Z. Kresin Stuart A. Wolf Yu. N. Ovchinnikov 《Journal of Superconductivity》1996,9(3):329-333
The value of the critical temperature of the cuprates correlates with the doping level and is affected by the interplay of two competing factors: (1) the increase in carrier concentration, and (2) the pair-breaking effect of magnetic impurities. An analysis of the temperature dependence of the critical field leads to the conclusion that magnetic impurities are present even in a sample with the maximum observed value ofT
c.A new parameter, intrinsicT
c (T
cintr), which is its value in the absence of magnetic impurities, is introduced. The maximum value ofT
cintr, which corresponds to the maximum doping level, appears to be similar for different cuprates and to be equal to 160–170 K. This is the upper limit ofT
c in the cuprates. 相似文献