The basic principles of activated charcoal filtration chromatography and its use in recovering L-tyrosinefrom L-cystine waste were presented in ths paper. 相似文献
Passive methods for radon measurements, especially those based on radon adsorption, require observation of proper calibration methods.
The calibration method for diffusion-barrier charcoal detectors in a small (211 dm3) radon chamber has been proposed. The theoretical dependence of radon concentration vs. time inside the chamber during the exposure of charcoal detectors has been obtained and verified experimentally. For this purpose, the chamber volume as well as diffusion and adsorption parameters of the detector were taken into consideration.
For two types of detectors the conformity of calibration factors obtained in two ways: calculated from theoretical points (550 or 683 Bqm−3/cps depending on detector type) and from experimental points (553 or 691 Bqm−3/cps), was achieved.
The proposed method makes it possible to calibrate different kinds of radon-adsorbing detectors (not only charcoal canisters) in small chambers without the necessity of using any reference, active device. 相似文献
In order to develop a suitable reactor for the biomethanation of high-strength salty cheese whey, the performance of anaerobic
upflow fixed-film reactors packed with different support materials, such as charcoal, gravel, brick pieces, pumicestones,
and PVC pieces, has been studied. The charcoal-bedded reactor gave the best performance, with the maximum gas production (3.3
L/L digester/d) and an enriched methane content (69% CH4). Temperature and hydraulic retention time were optimized, with the ultimate aim of improving biomethanation. Maximum gas
production (3.3 L/L digester/d) was achieved at a hydraulic retention time of 2 d at 40°C. 相似文献
A comparative study on the sorption behaviour of tungsten and rhenium between anion exchange resin, charcoal and alumina and aqueous media of HNO3, HCl and NaCl were carried out. The equilibrium distribution coefficient obtained for the different systems were evaluated and discussed in terms of the separation factor between W and Re. It is found that the systems based on alumina and HCl or NaCl are the most promising systems to be used for development of 188W-188Re generator. The capacity of a chromatographic column loaded with alumina for 188W from 0.01 M HCl, 0.7% NaCl and 1.2% NaCl was found to equals 75.3, 91.0 and 126.0 mg/cm, respectively. A recommended procedure was adopted for 188W-188Re generator. Es wurde eine Vergleichsuntersuchung zum Sorptionsverhalten von W und Re zwischen einem Anionenaustauscherharz einer Aktivkohle und einer Tonerde und den wüβirigen Lösungen von HN03, HCl and NaCl ausgeführt. Die Gleichgeiwichlsverteilungskoeffizienten der unterschiedlichen Systeme wurden bestimmt und als Trennfaktoren zwischen W und Re diskutiert. Es wurde gefunden, daβ sich das System Tonerde/HCl oder NaCl sehr als Trennsystem für die Entuwicklung eines 188W188Re-Generators eignet. Die Kapazitäten einer mit Tonerde gefüllten Säule für 188W mit 0.01 M HCl, 0.7% NaCl und 1.2% NaCl betrugen entsprechend 75.3, 90.0 und 126.0 mg/cm. Es wird eine geeignete Trennmethode für einen 188.188 Re-Generator empfohlen. 相似文献
The preparation and properties of wood–plastic composites (WPCs) based on acrylonitrile–butadiene–styrene (ABS) and bamboo fibers (BFs) are described. The BFs were first modified by alkali treatment in order to improve their adhesion to an ABS matrix. The BF modifications were monitored by Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). Styrene–maleic anhydride (SMA) copolymer, as a compatibilizer, was added to both the untreated and alkali-treated composites. The changes in the structure and the properties resulting from these treatments were observed by the SEM and mechanical tests. The experimental results indicated that both the alkali treatment of the BF and the inclusion of the SMA copolymer improved the interactions between the BF and ABS matrix, and promoted better mechanical properties of the composites. 相似文献