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41.
In the modern analogue design, Transistor Level Fault Simulation (TLFS) plays the important part since every fault in the
whole circuit has to be simulated at that level. Unfortunately, it is a very CPU intensive task even though it maintains the
high accuracy. Therefore, High Level Fault Modeling (HLFM) and High Level Fault Simulation (HLFS) are required in order to
alleviate the efforts of simulation. In this paper, different HLFM approaches are reviewed at the device level during last
two decades. We clarify their domains of application and evaluate their strengths and current limitations. We also analyze
causes of faults and introduce various test approaches. 相似文献
42.
MacDonald Penny A.; Antony Martin M.; MacLeod Colin M.; Swinson Richard P. 《Canadian Metallurgical Quarterly》1999,108(4):679
Negative priming—the slowing of a response to an item that was recently ignored—was investigated in three groups: obsessive-compulsive disorder (OCD) checkers, OCD noncheckers, and nonclinical control participants. All groups performed both a standard negative priming task, selecting targets based on a perceptual feature (i.e., color), and a modified negative priming task, selecting targets based on a semantic feature (i.e., referent size). All three groups demonstrated significant negative priming in both tasks, although the negative priming was much larger in the novel, semantic task than in the common perceptual one. The findings suggest that patients with OCD do not demonstrate impairments in negative priming, contrary to earlier claims (Enright & Beech, 1990, 1993a, 1993b; Enright, Beech, & Claridge, 1995). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
43.
Autoclave cure simulation of composite structures applying implicit and explicit FE techniques 总被引:1,自引:0,他引:1
Gasser F. Abdelal Antony Robotham Wesley Cantwell 《International Journal of Mechanics and Materials in Design》2013,9(1):55-63
Simulation of the autoclave manufacturing technique of composites can yield a preliminary estimation of induced residual thermal stresses and deformations that affect component fatigue life, and required tolerances for assembly. In this paper, an approach is proposed to simulate the autoclave manufacturing technique for unidirectional composites. The proposed approach consists of three modules. The first module is a thermo-chemical model to estimate the temperature and the degree of cure distributions in the composite part during the cure cycle. The second and third modules are a sequential stress analysis using FE-implicit and FE-explicit respectively. User-material subroutine is used to model the viscoelastic properties of the material based on theory of micromechanics. 相似文献
44.
Howe Alexandra; Pit-ten Cate Ineke M.; Brown Antony; Hadwin Julie A. 《Canadian Metallurgical Quarterly》2008,20(3):305
In this study, we investigated a new instrument: the Southampton Test of Empathy for Preschoolers (STEP). The test incorporated 8 video vignettes of children in emotional scenarios, assessing a child's ability to understand (STEP-UND) and share (STEP-SHA) in the emotional experience of a story protagonist. Each vignette included 4 emotions (angry, happy, fearful, sad) that reflected emotion judgments based on the protagonist's facial expression, situation, verbal cues, and desire. The STEP was administered to 39 preschool children, and internal reliability, concurrent validity, and construct validity were addressed. The results showed good internal consistency. They also highlighted moderate concurrent validity with parent-rated empathy, a measure of facial indices, and construct validity with teacher-rated prosocial behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
45.
Surfactant‐mediated synthesis of polyhydroxybutyrate (PHB) nanoparticles for sustained drug delivery
Senthilkumar Pachiyappan Dawn Shanmuganatham Selvanantham Sree Samanvitha Kuppa Saipriya Chandrasekaran Antony Vincent Samrot 《IET nanobiotechnology / IET》2019,13(4):416
In this study, polyhydroxybutyrate (PHB) nanoparticles were synthesised following nanoprecipitation method having different solvents and surfactant (Tween 80) concentrations. In this study, PHB nanoparticles were encapsulated with curcumin and subjected for sustained curcumin delivery. Both the curcumin loaded and unloaded PHB nanoparticles were characterised using FTIR, SEM, and AFM. Sizes of the particles were found to be between 60 and 300 nm. The drug encapsulation efficiency and in vitro drug release of the nanoparticles were analysed. Antibacterial activity and anticancer activity were also evaluated. The LC50 values of most of the nanoparticles were found to be between 10 and 20 µg/100 µl, anticancer activity of curcumin loaded PHB nanoparticles were further confirmed by AO/PI staining and mitochondrial depolarisation assay.Inspec keywords: encapsulation, cancer, scanning electron microscopy, nanoparticles, surfactants, drugs, nanofabrication, antibacterial activity, biomedical materials, drug delivery systems, polymers, nanomedicine, Fourier transform infrared spectra, precipitation (physical chemistry), atomic force microscopy, particle sizeOther keywords: surfactant‐mediated synthesis, polyhydroxybutyrate nanoparticles, sustained drug delivery, surfactant concentrations, PHB nanoparticles, sustained curcumin delivery, drug encapsulation efficiency, anticancer activity, in vitro drug release, nanoprecipitation method, Tween 80, FTIR spectra, SEM, AFM, particle sizes, antibacterial activity, AO‐PI staining, mitochondrial depolarisation assay 相似文献
46.
Water is a basic necessity of man. Economical and efficient production or recycling of water is very much needed in today's world. Solar still has emerged as a life-saving technology to distil brackish water and produce drinkable water using solar energy. The aim of this project was to improve the performance of solar still by adding an air blower which creates a bubbling effect in the still due to which the evaporation rate increases. The bubbling effect using the blower makes the raw water to circulate and to distribute heat energy equally. The evaporated raw water was collected in the glass plate as drop particles. The drop condenses due to ambient air and finally distillate output is collected in the jar, which is placed outside the still. The solar still with air blower arrangement gave higher difference in efficiency and higher distilled output when compared with solar still without an air blower. 相似文献
47.
Van Driessche B Tafforeau L Hentges P Carr AM Vandenhaute J 《Yeast (Chichester, England)》2005,22(13):1061-1068
The one-step PCR-mediated technique used for modification of chromosomal loci is a powerful tool for functional analysis in yeast. Both Saccharomyces cerevisiae and Schizosaccharomyces pombe are amenable to this technique. However, the scarce availability of selectable markers for Sz. pombe hampers the easy use of this technique in this species. Here, we describe the construction of new vectors deriving from the pFA6a family, which are suitable for tagging in both yeasts owing to the presence of a nourseothricin-resistance cassette. These plasmids allow various gene manipulations at chromosomal loci, viz. N- and C-terminal tagging with 3HA (haemagglutinin) or 13Myc epitopes, GST (glutathione S-transferase), 4TAP (tandem affinity purification) and several GFP (green fluorescent protein) isoforms. For N-terminal modifications, the use of different promoters allows constitutive (PADH1) or regulatable (PGAL1) promoters for S. cerevisiae and derivatives of Pnmt1 for Sz. pombe expression. 相似文献
48.
V. D. Tathavadkar A. Jha M. P. Antony 《Metallurgical and Materials Transactions B》2001,32(4):593-602
Soda-ash roasting of the chromite mineral is commonly used worldwide for the production of watersoluble sodium chromate. The
formation of sodium chromate during the soda-ash roasting reaction depends on the oxygen partial pressure and availability
of oxygen at the reaction front. The effects of temperature, oxygen partial pressure, charge composition, and their roles
on the overall roasting reaction were studied in order to analyze the reaction mechanism. The influence of process parameters
such as the addition of alkali and process residue as the filler material on the overall reaction rate is discussed. The rate-determining
steps for the soda-ash roasting reaction are analyzed. The importance of the binary Na2CO3-Na2CrO4 liquid phase during the reaction in determining its speed is also examined. It is shown that the experimental results for
the roasting reaction can be best described by the Ginstling and Brounshtein (GB) equation for diffusion-controlled kinetics.
From the measured kinetics data, the apparent activation energy for the roasting reaction was calculated to be between 180
and 190 kJ · mol−1 in the temperature range from 1023 to 1210 K and between 35 and 40 kJ · mol−1 above 1210 K. 相似文献
49.
Antony Cyril Arulrajan Palaniappan Subramanian Ramesh Kumar Singh Alex Schechter 《Israel journal of chemistry》2020,60(5-6):563-569
Developing Pt-free catalysts for hydrogen oxidation reaction (HOR) in alkaline solution is becoming a key challenge in the development of anion exchange membrane fuel cells and electrochemical reactors. Herein, we present the preparation, HOR activity, and stability of Pd-decorated tungsten (Pd-d-W) catalysts. The Pd-d-W catalysts were prepared by the chemically activated surface of tungsten nanoparticles by Pd ions. The resultant bimetallic catalysts consisted of crystalline phases of both Pd and W nanoparticles. The CO stripping voltammograms and H-desorption (Hdes) peak potential of hydrogen desorption in Pd suggests that the enhancement of HOR catalytic activity observed in Pd-d-W catalyst can be ascribed to the modification of electronic property of Pd and availability of OHad near-surface Pd atoms. 相似文献
50.
Baciu M Sebai SC Ces O Mulet X Clarke JA Shearman GC Law RV Templer RH Plisson C Parker CA Gee A 《Philosophical transactions. Series A, Mathematical, physical, and engineering sciences》2006,364(1847):2597-2614
Drug molecules must cross multiple cell membrane barriers to reach their site of action. We present evidence that one of the largest classes of pharmaceutical drug molecules, the cationic amphiphilic drugs (CADs), does so via a catalytic reaction that degrades the phospholipid fabric of the membrane. We find that CADs partition rapidly to the polar-apolar region of the membrane. At physiological pH, the protonated groups on the CAD catalyse the acid hydrolysis of the ester linkage present in the phospholipid chains, producing a fatty acid and a single-chain lipid. The single-chain lipids rapidly destabilize the membrane, causing membranous fragments to separate and diffuse away from the host. These membrane fragments carry the drug molecules with them. The entire process, from drug adsorption to drug release within micelles, occurs on a time-scale of seconds, compatible with in vivo drug diffusion rates. Given the rate at which the reaction occurs, it is probable that this process is a significant mechanism for drug transport. 相似文献