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1.
Recognition of adulteration by other oils via direct analysis of the minor components (“sterol fraction”) is shown for olive oil. 10 % of various oils were admixed, the free alcohols silylated and the minor components analyzed by on-line coupled LC-GC-FID. For most oils, even smaller additions can be recognized. Admixed oils can no longer be determined, however, if their minor components have been removed by strong raffination. Bleaching of rapeseed oil with 7% of earth at 180 °C, in fact, completely removed free and esterified sterols.  相似文献   
2.
This paper compares conventional and cryogenic cooling in the deep hole drilling of carbon fiber reinforced polymer (CFRP)/Ti stacks. Various parameters are taken into account to find if the use of cryogenic coolant is justified by the improvement of the final results. Both the thrust and the torque were acquired continuously during the machining operations and compared both in average and distribution. The use of a cryogenic coolant brings a reduction in thrust force and torque without any sensible drawback. Overall the results prove that cryogenic drilling is a suitable technology for CFRP/Ti stack drill.  相似文献   
3.
This paper focuses on the control system for an autonomous robot for the surveillance of indoor environments. Our approach proposes a matrix-based formalism which allows us to merge in a single framework discrete-event supervisory control, conflict resolution and reactive control. As a consequence, the robot is able to autonomously handle high level tasks as well as low-level behaviors, solving control and decision-making issues simultaneously. Moreover, the matrix-based controller is modular and can be easily reconfigured if mission characteristics or robot hardware configuration change. An illustrative example and a report on experimental investigations are provided to illustrate the main features of the proposed approach.  相似文献   
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Process capability indices Cp, Cpk, and Cpm are still nowadays widely used in industry—thanks to their easy formulation and implementation. This paper aims to give new mathematical insights in order to support their use in decision‐making via hypothesis testing. The minimum sample size usually needed in the applications to achieve fixed significance level and power is reported in light of the new mathematical aspects for Cpk and Cpm, which avoid misleading conclusions and the use of extensive numerical experiments. In addition, power curves for Cpk and Cpm, which have not previously appeared in the literature before, are also presented. Lastly, easy‐to‐follow diagrams for hypothesis testing with Cpk and Cpm and two critical scenarios for Cpm are included in the paper to facilitate the applicative use and the comprehension of the novel inferential aspects. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
6.
The inhibitory deficit hypothesis has often been cited as a possible explanation for cognitive changes related to age. The aim of this study was to develop a new procedure for evaluating effortful inhibition on the basis of the comprehension of metaphors. Our experiment was carried out on younger and older adults, in whom we also measured inhibitory capacity, working memory, and processing speed. The results show that older participants required a longer time and made more frequent errors in rejecting metaphors versus literally false statements. The interference effect was predicted by the psychometric tests designed to evaluate inhibition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
7.
To evaluate the efficacy of continuous administration of 50% nitrous oxide in oxygen for reducing pain during flexible fiberoptic bronchoscopy 32 children aged 3-60 months were randomly assigned to an experimental or a control group. Indications for endoscopy included persistent atelectasis (6), wheezing (10) cystic fibrosis (2) pneumonia (11) persistent cough (3). All patients received Midazolam (0.3 mg/kg) atropine (20 mcg/kg) intra rectaly 20 minutes before the procedure. The flexible fiberoptic bronchoscope (Olympus BF3C4) was inserted transnasally through a face mask. Topical anesthesia with 1% lidocaine hydrochloride (3 mg/kg) was applied to the nose, larynx, trachea and bronchial tree over 15 minutes through the suction chanel of the bronchoscope. All patients were monitored with a pulse oximeter and a cardiac monitor. The experimental group (n = 16) received 50% nitrous oxide in oxygen prior (3 minutes) and during flexible fiberoptic bronchoscopy, the control group (n = 16) received only oxygen. We measured pain of the children by a behavioral observation scale (Children's Hospital of Eastern Ontario Pain Scale: CHEOPS) at each phase of topical anesthesia during bronchoscopy in the two groups. At the end of bronchoscopy physician's satisfaction was scored by a visual analogue scale (VAS 0-100) in which 0 corresponded to absence of satisfaction. Nitrous oxide was associated with lesser pain scores than those with oxygen. Physician significantly preferred these procedure compared with oxygen. No complication occurred during procedure. Combined with local anesthesia midazolam and atropin the administration of 50% nitrous oxide in oxygen seems a better choice for flexible fiberoptic bronchoscopy in children and should be used routinely.  相似文献   
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The extrabulbar olfactory projections (EBOP) is a collection of nerve fibers that originate from primary olfactory receptor neurons. These fibers penetrate into the brain, bypassing the olfactory bulbs (OBs). While the presence of an EBOP has been well established in teleosts, here we morphologically characterize the EBOP structure in four species each with a different morphological relationship of OB with the ventral telencephalic area. Tract‐tracing methods (carbocyanine DiI/DIA and biocytin) were used. FMRFamide immunoreactive nervus terminalis (NT) components were also visualized to define any neuroanatomical relationship between the NT and EBOP. Unilateral DiI/DiA application to the olfactory chamber stained the entire olfactory epithelium, olfactory nerve fibers, and ipsilateral olfactory bulb. Labeled primary olfactory fibers running ventromedially as extrabulbar primary olfactory projections reached various regions of the secondary prosencephalon. Only in Moenkhausia sanctaefilomenae (no olfactory peduncle) did lipophilic tracer‐labeled fibers reach the ipsilateral mesencephalon. The combination of tracing techniques and FMRFamide immunohistochemistry revealed a substantial overlap of the label along the olfactory pathways as well as in the anterior secondary prosencephalon. However, FMRFamide immunoreactivity was never colocalized in the same cellular or fiber component as visualized using tracer molecules. Our results showed a certain uniformity in the neuroanatomy and extension of EBOP in all four species, independent of the pedunculate feature of the OBs. The present study also provided additional evidence to support the view that EBOP and FMRFamide immunoreactive components of the NT are separate anatomical entities. Microsc. Res. Tech. 78:268–276, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
10.
The influence of axial fluid conduction on low Péclet number flows in the thermal entrance region of long circular tubes is investigated in this theoretical study. The convective heat transport of viscous fluids relates to a specific condition under which the first part of the tube ( x h 0) is insulated and the second part of the tube ( x > 0) receives a heat flux of uniform intensity. A conjugate one-dimensional lumped model produces a solution of compressed algebraic form that is able to deliver dependable mean bulk temperatures that are in perfect agreement with those obtained numerically by the formal conjugate two-dimensional distributed model. As a by-product of the succession of algebraic calculations within the platform of the lumped model, the critical Péclet number Pe cr has been easily quantified. This number is a figure-of-merit of remarkable importance in the modeling of forced heat convection in tubes because it establishes the threshold between two contrasting situations: one embracing axial fluid conduction (finite Pe) and the other implicating negligible axial fluid conduction (Pe M X ). In addition, the local wall temperatures were calculated with an approximate engineering procedure, showing good agreement with those determined numerically by the formal conjugate two-dimensional distributed model.  相似文献   
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