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101.
Sing Teang Kong Hai-Shu Lin Jianhong Ching Huiqing Xie Paul C. Ho 《International journal of molecular sciences》2022,23(13)
The immediate and delayed metabolic changes in rats treated with valproate (VPA), a drug used for the treatment of epilepsy, were profiled. An established approach using dried blood spots (DBS) as sample matrices for gas chromatography/mass spectrometry-based metabolomics profiling was modified using double solvents in the extraction of analytes. With the modified method, some of the previously undetectable metabolites were recovered and subtle differences in the metabolic changes upon exposure to a single dose of VPA between males and female rats were identified. In male rats, changes in 2-hydroxybutyric acid, pipecolic acid, tetratriacontane and stearic acid were found between the control and treatment groups at various time points from 2.5 h up to 24 h. In contrast, such differences were not observed in female rats, which could be caused by the vast inter-individual variations in metabolite levels within the female group. Based on the measured DBS drug concentrations, clearance and apparent volume of distribution of VPA were estimated and the values were found to be comparable to those estimated previously from full blood drug concentrations. The current study indicated that DBS is a powerful tool to monitor drug levels and metabolic changes in response to drug treatment. 相似文献
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由于SF6气体在超低温下产生部分液化,使得SF6开关设备内的SF6气体密度下降,降低了SF6开关设备的开断能力和绝缘水平,无法保证SF6开关设备的可靠运行。为此,本文作者提出了采用电加热装置对SF6开关设备中的SF6气体进行加热,使SF6气体的温度可以始终高于SF6气体液化温度的解决方案。同时,本文对超低温环境下的其他解决方案也进行了分析比较。 相似文献
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A gas sensor based on a -alumina thick film was recently developed on a laboratory scale. This sensor can be successfully used for selective detection of CO and NOx, resulting from an appropriate choice of the working temperature of the sensing element. This paper deals with the approach of the industrial transfer of the sensor prototype, mainly concerning the scale-up of the screen-printing procedure from a hand-operated apparatus to an industrial production machine. Many parameters were already investigated during the laboratory development, namely the ink composition in terms of organic/inorganic component ratio, the type and amount of the liquid dispersant and rheological agent, the composition and softening temperature of the binder, the -alumina/binder weight ratio. During the industrial transfer, some other parameters must be considered, such as the particle size distribution of the ceramic components of the ink, the influence of the mesh number of the screen fabric on the surface texture of the -alumina film, the viscosity performances of the ink as a function of the applied shear rate and ageing. A common commercial metallic paste was also used as reference for optimizing the characteristics of the -alumina based ink. 相似文献
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根据嘉兴发电厂一期2×300MW机组烟气湿法脱硫装置的实际运行情况,分析GGH积灰结垢的原因,提出了相应的对策与控制措施,保障脱硫系统安全、可靠和经济运行。 相似文献
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