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111.
By measuring the electrical properties of the catalyst coating itself, one can observe directly and in situ the state of TWC, LNT, and SCR catalysts. Two principles are possible: a contact method, for which the coating is applied to planar electrodes and the electrical impedance is measured, and a non-contact method, in which the coating material is penetrated by radio frequency waves. In either case, the catalyst state is directly correlated with the measured transmission or reflection characteristics of the electrical sensors.  相似文献   
112.
AH 26 releases formaldehyde   总被引:1,自引:0,他引:1  
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113.
In the present work an automated Continuous Compression Moulding Technique for the manufacture of stringers in continuous length is presented. The method combines pultrusion and hot-pressing. The technique is utilized for the production of L-shape stringers which are widely applied in aerospace constructions. The investigation was carried out on carbon reinforced PEEK (C/PEEK), as well as, for comparison, on the thermoplastic composites carbon reinforced polyethersulfon (C/PES), glass and carbon reinforced polyphenylene-sulfide (G/PPS, C/PPS) and Kevlar reinforced Polyamide 6 (K/PA 6).

For the materials investigated the optimized process parameters for manufacturing the L-shape stringers were derived experimentally. To achieve this goal, the quality of the produced parts was controlled by using non-destructive testing techniques. Parts providing satisfactory quality were also tested destructively to measure their mechanical properties. The investigation results have shown the suitability of the technique to produce continuous length stringers.  相似文献   

114.
Ciguatera fish poisoning is the most common form of toxin-related food poisoning in the United States. Originating from dinoflagellates living on coral reefs, it is spread up the food and affects humans who ingest the ciguatoxic fish. Ciguatera is primarily endemic in tropical regions of the world. It is a self-limiting disease that presents with characteristic gastrointestinal, neurological, and cardiovascular symptoms. Recent advances in testing procedures and symptom recognition has improved ciguatoxin identification and clinical management. However, there is still a need for better diagnostic, preventive, and reporting protocols to more accurately study and understand this diverse and temporarily debilitating clinical syndrome.  相似文献   
115.
Twelve healthy male volunteers participated in this open, randomized, placebo-controlled, two-way crossover study to investigate the effects of cimetidine on the steady-state pharmacokinetics of oral trovafloxacin. Volunteers were randomized to receive either 400 mg cimetidine twice daily or placebo for 5 days. From day 3-5, volunteers received 200 mg trovafloxacin once daily in addition to either cimetidine or placebo. After a minimum 7-day washout period, the study was repeated: those volunteers who received placebo during the first study period were administered cimetidine, and vice versa. The maximum observed serum trovafloxacin concentration, the area under the concentration-time curve of trovafloxacin within the dosing interval of 24 h and the earliest time to the maximum serum concentration for trovafloxacin in volunteers receiving concomitant cimetidine were 2.4 microg/ml. 27.8 microg x h/ml and 1.4 h, respectively, compared with 2.5 microg/ml, 27.1 microg x h/ml and 1.5 h, respectively, in volunteers receiving concomitant placebo. Thus. multiple dosing with cimetidine had no significant effect on the absorption or disposition of trovafloxacin at steady state. Co-administration of cimetidine and trovafloxacin was also well tolerated and without serious adverse effects.  相似文献   
116.
The project is about phenomenology and its elements. It points out the essential ideas of existential phenomenology interpreted by Maurice Merleau-Ponty's ideas and tries to connect this philosophy to nursing world.  相似文献   
117.
118.
The objective of the present study was to investigate the interactions of dietary K intake typical for forage-based diets on Mg balance in lactating dairy cows. Six lactating multiparous cows of the Swedish Red and White breed in midlactation were used. Two concentrations of Mg (1.9 and 4.3 g/kg of dry matter) and 3 concentrations of K (19, 28, and 37 g of K/kg of dry matter) were obtained by adding appropriate amounts of MgO and KHCO3 to the diet. The experimental setup was a 6 × 6 Latin square design with a 2 × 3 factorial arrangement of treatments. Each experimental period lasted 14 d (9-d treatment adaptation period and 5-d data collection). There was no effect of Mg or K dietary supplementation on milk yield. Supplementing the ration with K did not significantly affect the Mg apparent absorption, urinary Mg excretion, or plasma Mg concentration. The Mg balance, estimated as the Mg losses in milk and urine, was positively related to Mg intake but not affected by K intake. The amount of apparently digested Mg was related to the Mg balance. The apparent digestibility ranged from 0.12 to 0.24 with no effect of mineral supplementation. There was a significant curvilinear relationship between plasma Mg and urinary Mg excretion, with a more marked increase in urinary Mg excretion at higher plasma levels of Mg.  相似文献   
119.
120.
Prolonged sleep deprivation elicits a significant elevation of the plasma level of free tryptophan which appears to be involved in increased excretion of 5-HIAA during this state through enhanced 5-HT synthesis.  相似文献   
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