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1.
With the aim of determining the possibilities of directly upgrading the liquid obtained from carbohydrate fermentation, the effect of operating conditions (temperature, space time, water content in the feed) has been studied in the catalytic transformation of aqueous ethanol into hydrocarbons on an HZSM‐5 zeolite in an isothermal fixed bed reactor. Special attention has been paid to the effect of water content on the yield, product distribution and catalyst deactivation. Although deactivation by coke decreases as the water content is increased, this content must be limited at 450 °C and higher temperatures in order to avoid irreversible deactivation of the catalyst by dealumination. © 2002 Society of Chemical Industry  相似文献   
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Higher performance designs for rotating anode X-ray tubes have increased the average rotating anode temperature from below 1100 °C to well above 1300 °C. This temperature increase has accelerated the formation of carbon monoxide by reaction of carbon from the alloy substrate with oxygen from the emissive coating. The dominant carbon source is thought to be Mo2C grain boundary precipitates in the TZM molybdenum alloy substrate. The dominant oxygen source is thought to be TiO in the emissive coating. Placement of a monocarbide-forming reactive layer between the alloy substrate and the emissive coating has been demonstrated to lower the thermodynamic activity of the carbon source and dramatically reduce the rate of formation of carbon monoxide.  相似文献   
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This study measures the effect of lossy image compression (JPEG 2000 and JPG) on the digital classification of crop areas. The results provide new insights into the influence of compression on the quality of the cartography produced. Both a multitemporal and a single-date classification approach were analysed. With the multitemporal approach, it is possible to use high compression ratios (CRs), up to 20:1 or even 100:1, and the overall accuracy of the classification is similar to that obtained with the original images. Moreover, the classified area is similar or even greater (fewer pixels are uncertain). For a single-date approach, it is only advisable to use 3D-JPEG 2000 at CRs up to 20:1. The optimum CR is also affected by landscape fragmentation (fragmented images tolerate less compression) and the classification method (hybrid classifiers are affected less than the maximum likelihood and minimum distance classifiers). Finally, classifications from compressed images have less ‘salt and pepper’ effect than those obtained from the originals, especially when JPEG 2000 (3D or not) is used.  相似文献   
4.
Ten strains of lactic acid bacteria were isolated from a dry fermented sausage and tested for stimulation or inhibition of the viability of Vero and myeloma cells. They did not significantly affect the viability of Vero cells but two isolates (CBL/H and CBL/K) showed a strong and moderate inhibition of the myeloma cell viability (at 108 CFU mL?1, 17.6 and 33.2%, respectively, survival of myeloma cells). The isolates were identified as Lactobacillus sakei by DNA sequencing of the 16S rRNA products of a polymerase chain reaction. No protective effect was found, at the concentrations used, against cytotoxicity of N‐nitrosamines. To test the effect of L. sakei CBL/H and CBL/K on cytokine production [tumour necrosis factor alpha (TNF‐α), interleukin‐1β (IL‐1β) and interleukin‐8 (IL‐8)], the human macrophage cell line (THP‐1) was cultured in the presence and absence of lipopolysaccharide (LPS). Lactobacillus sakei CBL/H and CBL/K induced IL‐1β and IL‐8 release when cells were stimulated with and without LPS. However there was TNF‐α release only in the presence of the LPS.  相似文献   
5.
INTRODUCTION: The place of platelet antiaggregants in the aetiology of intracerebral hemorrhage (IH) has not been extensively studied. OBJECTIVE: To analyze the characteristics of IH in patients treated with platelet antiaggregants and the possible clinical and prognostic differences from other primary IH. PATIENTS AND METHODS: A retrospective study of patients admitted to hospital with primary IH from 1985 to 1997. The cases were IH patients while being treated with platelet antiaggregants. For each case we selected two controls with IH and similar age and IH risk factors. The following data was analyzed: start of clinical condition; type, dose, indication and duration of treatment with antiaggregants; mortality, localization, volume and extension of IH to the ventricles. The last four variables were compared with the control group using the ji squared test (chi 2) and the t student test. RESULTS: 21one patients had a primary IH while being treated with antiaggregants: 20 with salicylates (17 aspirin and 3 riflusal) and one with ticlopidine. The dose of aspirin was 500 mg or less in 90% of the cases. In the group treated with salicylates, this was given for more than 20 months in 90% of the cases. Initially there was no clinical progression in any case. No significant differences were observed between the variable compared, although there was a tendency to greater volume, extension to the ventricles and mortality in the group treated with antiaggregants. CONCLUSIONS: More studies with larger numbers of patients are necessary to be able to confirm the tendencies observed.  相似文献   
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This paper explores the influence of regional climate variability on the elasticity of price for residential water demand in Spain. The data comes from the Spanish Survey of Family Budget (INE 2012), a national based survey of household living conditions including more than 15,000 observations. The econometric analysis included other determinants of residential water demand in Spain such as income and household characteristics. In line with the broad literature, the demand for water in Spain is found to be inelastic, although price elasticity differs notably when accounting for different climatic regions in the territory. The results have noteworthy policy implications as water pricing is considered an efficient means of long term sustainable planning of water resources management. The results imply that policy makers may have reasons to explore differentiating the impacts of water efficiency measures by region.  相似文献   
9.
Multimedia Tools and Applications - Natural gestures are a desirable feature for a humanoid robot, as they are presumed to elicit a more comfortable interaction in people. With this aim in mind, we...  相似文献   
10.
The results of the catalytic transformation on HZSM‐5 zeolite of mixtures of components of biomass pyrolysis oil in the 673–723 K temperature range are evidence of the need for previously separating certain components (aldehydes, oxyphenols and furfural) that undergo severe thermal degradation by forming carbonaceous deposits at the reactor inlet ducts and on the catalyst itself. The deactivation of the catalyst is a consequence of the deposition of two different types of coke: one of catalytic origin (similar to that generated in the transformation of methanol and bioethanol) and the other of thermal origin, which is produced by the aforementioned degradation. The remaining oxygenate components react to each other with synergistic effect, which means that their reactivity is higher than that of the pure components. The results show that the aqueous fraction of biomass pyrolysis oil may be transformed into hydrocarbons on acid catalysts similarly to the more familiar transformation of methanol and bioethanol. Copyright © 2005 Society of Chemical Industry  相似文献   
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