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141.
Although Affordance Theory has become increasingly influential in the Information Systems (IS) literature, the exact process through which the affordances of IT are actualised is less studied. In this paper, we build on a realist ontology of affordance and an interpretive epistemology of how affordances are perceived and actualised to trace the process of actualisation. On the basis of insights drawn from a case study of a telemedicine project in a remote mountainous region of Nepal, we develop a concept, which we call the “Trajectory of Affordances.” Trajectory of Affordances captures the complex relations between affordances of IT and the role of goal‐oriented actors who perceive and then play a vital role in actualising them, using capabilities that are enabled by facilitating conditions to take the necessary action. Trajectory of Affordances shows that the affordances of IT can travel from perception to actualisation through multiple paths, sometimes clustering together, and in the process, often lead to the emergence of new affordances. 相似文献
142.
A. Iliyas Z. Sarshar H. M. Zahedi-Niaki M. Eić S. Kaliaguine 《Topics in Catalysis》2009,52(13-20):1860-1867
One-dimensional channel molecular sieves were synthesized and tested as hydrocarbon traps using toluene and ethylene as heavy and light HC probe molecules, respectively. Binary TPD traces of these two gases allow a systematic comparison of the adsorption/desorption behavior of molecular sieves. These results show a drastic difference between molecular sieves with 10 oxygen ring apertures (10R) and 12R. Ammonia TPD traces of the series of 12R molecular sieves allow to rationalize the different ethylene/toluene TPD traces. 相似文献
143.
粒度对炭—石墨材料的生产工艺及性能的影响 总被引:2,自引:1,他引:1
对炭-石墨材料的最大粒度的确定、粒度的计算、粒度对粘结剂用量及对性能的影响进行了系统地研究和总结。 相似文献
144.
Khin Maung Latt C. Sher-Yi T. Osipowicz K. Lee Y. K. Lee 《Journal of Materials Science》2001,36(23):5705-5712
This work investigated the properties of ionized metal plasma (IMP) deposited copper (Cu) and chemical vapor deposited (CVD) Cu on IMP-TaN (tantalum nitride) diffusion barrier in the Cu(200 nm)/TaN(30 nm)/SiO2(250 nm)/Si multi-layer structure. The IMP-Cu film deposited on IMP-TaN had a preferred orientation (220) with a grain size of around 30 nm and roughness (RMS) of 1.391 nm, while the CVD-Cu had a (111) preferred orientation with a grain size around 170 nm and roughness (RMS) of 15.416 nm as determined by atomic force microscopy (AFM) and x-ray diffraction (XRD) analyses. Thermal stability study of the structures was also performed by sheet resistance measurements, scanning electron microscopy (SEM), XRD and Rutherford backscattering spectroscopy (RBS). These results revealed that IMP-Cu on IMP-TaN has higher thermal stability, less intermixing and/or agglomeration than CVD-Cu on IMP-TaN at the same annealing temperatures. The higher thermal stability of IMP-Cu than CVD-Cu can be accounted by their difference in microstructure. The failure mechanisms of IMP-Cu and CVD-Cu in multiplayer structure were also discussed. 相似文献
145.
PA Deutchman RL Buvel KM Maung JW Norbury LW Townsend 《Canadian Metallurgical Quarterly》1986,33(1):396-398
We calculate the coherent production of pions from subthreshold to relativistic energies in heavy-ion collisions using a quantum, microscopic, many-body model. For the first time, in this approach, we use harmonic oscillator wave functions to describe shell-model information. The theoretical quantum mechanical results obtained for the pion spectra represent an important improvement over our previous microscopic, many-body calculations. 相似文献
146.
Giang T. Nguyen Ei L. Chan Takuya Tsuji Toshitsugu Tanaka Kimiaki Washino 《Advanced Powder Technology》2021,32(1):225-236
A resolved CFD–DEM coupling model for the simulation of particulate flows is proposed in this work. The Volume Penalisation (VP) method, which is a family of the continuous forcing Immersed Boundary (IB) method, is employed to express the particle–fluid interaction. A smooth mask function is used to avoid sharp transition between the solid (particle) and fluid domains that may cause numerical oscillation with moving particles. Optimal permeability is employed to reduce the model error associated with the VP method. It is determined as a function of only the interface thickness and fluid kinematic viscosity. The proposed model is accurate, easy to implement with any discretisation scheme, and only requires small computational overhead for particle–fluid interaction. Several simulations are performed to test the validity of the proposed model in various systems, i.e. from dilute to relatively dense flows, and the results show good agreement with the exact solution or empirical correlation. It is found that the error can be scaled with the ratio between the gap and interface thickness. The proposed model is also applied to predict the relative viscosity of suspensions and the density segregation in fluidised beds. 相似文献
147.
Yang CS Brown EE Hommerich UH Trivedi SB Samuels AC Snyder AP 《Applied spectroscopy》2007,61(3):321-326
Laser-induced breakdown spectroscopy (LIBS) is a powerful analytical technique for detecting and identifying trace elemental contaminants by monitoring the visible atomic emission from small plasmas. However, mid-infrared (MIR), generally referring to the wavelength range between 2.5 to 25 microm, molecular vibrational and rotational emissions generated by a sample during a LIBS event has not been reported. The LIBS investigations reported in the literature largely involve spectral analysis in the ultraviolet-visible-near-infrared (UV-VIS-NIR) region (less than 1 microm) to probe elemental composition and profiles. Measurements were made to probe the MIR emission from a LIBS event between 3 and 5.75 microm. Oxidation of the sputtered carbon atoms and/or carbon-containing fragments from the sample and atmospheric oxygen produced CO(2) and CO vibrational emission features from 4.2 to 4.8 microm. The LIBS MIR emission has the potential to augment the conventional UV-VIS electronic emission information with that in the MIR region. 相似文献
148.
Nasir N Yahya N Kashif M Daud H Akhtar MN Zaid HM Shafie A Teng LC 《Journal of nanoscience and nanotechnology》2011,11(3):2551-2554
This is our initial response towards preparation of nano-inductors garnet for high operating frequencies strontium iron garnet (Sr3Fe5O12) denoted as SrIG and yttrium iron garnet (Y3Fe5O12) denoted as YIG. The garnet nano crystals were prepared by novel sol-gel technique. The phase and crystal structure of the prepared samples were identified by using X-ray diffraction analysis. SEM images were done to reveal the surface morphology of the samples. Raman spectra was taken for yttrium iron garnet (Y3Fe5O12). The magnetic properties of the samples namely initial permeability (micro), relative loss factor (RLF) and quality factor (Q-Factor) were done by using LCR meter. From the XRD profile, both of the Y3Fe5O12 and Sr3Fe5O12 samples showed single phase garnet and crystallization had completely occurred at 900 degrees C for the SrIG and 950 degrees C for the YIG samples. The YIG sample showed extremely low RLF value (0.0082) and high density 4.623 g/cm3. Interesting however is the high Q factor (20-60) shown by the Sr3Fe5O12 sample from 20-100 MHz. This high performance magnetic property is attributed to the homogenous and cubical-like microstructure. The YIG particles were used as magnetic feeder for EM transmitter. It was observed that YIG magnetic feeder with the EM transmitter gave 39% higher magnetic field than without YIG magnetic feeder. 相似文献
149.
Chaw Jiang Lim Mahashanon Arumugam Chan Kiang Lim Gwendoline Cheng Lian Ee 《Journal of Natural Fibers》2020,17(5):726-737
ABSTRACTInvasive plants can grow rampantly and spread fast in large amount, which can be economically invoked for generating value-added products. In this study, lignocellulosic fiber was extracted from the leaf waste of a luxuriant invasive plant, Mikania micrantha Kunth-ex H.B.K. by mercerization process. After the alkaline treatment, the lignocellulosic biomass remained at 38.54% resulting from the large removal of extractive impurities. The lignocellulosic fraction in the mercerized leaf fiber was improved from 56.59% to 83.96%. The chemical composition analysis showed the cellulose fraction was increased by 11.17% while the hemicellulose and lignin fractions were found to be decreased by 4.89% and 6.28%, respectively. The FT-IR and TGA results further affirmed the change in chemical composition of the lignocellulosic fiber. Furthermore, an increase in cellulose fraction raised the fiber crystallinity index from 11.0% to 36.7%. The SEM study revealed that the surface morphology of lignocellulosic fiber changed from smooth surface into rough corrugated ridges, which affirmed the increase in crystallinity, resulting from the removal of wrapped cementing materials. In subsequent, the lignocellulosic fiber exhibited more pervious to water attack with an increase in moisture absorption from 119.22% to 410.19%. 相似文献
150.
Chaw Kyi-Tha-Thu Yuji Fujitani Seishiro Hirano Tin-Tin Win-Shwe 《International journal of molecular sciences》2023,24(1)
Recent epidemiological studies have reported significantly increasing hospital admission rates for mental disorders such as anxiety and depression, not only in adults but also in children and adolescents, indicating more research is needed for evaluation of the etiology and possible reduction and prevention of these disorders. The aim of the present study was to examine the associations between perinatal exposure to traffic-related air pollutants and anxiety-like behaviors and alterations in neurological and immunological markers in adulthood using a rat model. Sprague Dawley pregnant rats were exposed to clean air (control), diesel exhaust (DE) 101 ± 9 μg/m3 or diesel exhaust origin secondary organic aerosol (DE-SOA) 118 ± 23 μg/m3 from gestational day 14 to postnatal day 21. Anxiety-related behavioral tests including open field tests, elevated plus maze, light/dark transition tests and novelty-induced hypophagia were performed on 10-week-old rats. The hippocampal expression of neurotransmitters, neurotrophic factors, and inflammatory molecular markers was examined by real-time RT-PCR. Anxiety-like behaviors were observed in both male and female rat offspring exposed to DE or DE-SOA. Moreover, serotonin receptor (5HT1A), dopamine receptor (Drd2), brain-derived neurotrophic factor and vascular endothelial growth factor A mRNAs were significantly decreased, whereas interleukin-1β, cyclooxygenase-2, heme oxygenase-1 mRNAs and microglial activation were significantly increased in both male and female rats. These findings indicate that brain developmental period exposure to traffic-related air pollutants may induce anxiety-like behaviors via modulation of neurotransmitters, neurotrophic factors, and immunological molecular markers, triggering neuroinflammation and microglia activation in rats. 相似文献