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排序方式: 共有568条查询结果,搜索用时 15 毫秒
1.
The article presents the method of recycling aluminum industry fluorine-containing waste products to produce hydrogen fluoride. We carried out the estimate of the thermodynamic parameters of sulfuric acidic recycling of fluorine-containing waste products. We considered the necessity of waste products preliminary oxidizing roast stage to reduce carbonic constituent due to the interaction between carbonic constituent blocks of the sulfuric acid and waste products. We also carried out the researches for kinetic characteristics and to determine the optimal conditions for the to recycle sulfuric acidic in the fluorine-containing waste products.  相似文献   
2.
There is an increasing demand for quantitative data on metabolite exposure triggered by regulatory guidances. This contribution describes the accuracy of nanoelectrospray ionization mass spectrometry response of drug compounds and their metabolites from biological matrices compared with radiometric quantification. This is a comprehensive investigation of a set of real-life pharmaceutical compounds in relevant matrices such as urine, bile, feces and plasma. The data suggest that nanoelectrospray mass spectrometry can be used for semi-quantitation of metabolites in the absence of reference standards. Therefore, this approach is suitable to screen out non-relevant metabolites early in development as long as an adequate analytical error margin is applied thus balancing risks and resources.  相似文献   
3.
This paper reviews ways in which radioactive tracer techniques can he used to improve the efficiency of a caprolactam production plant, Residence time spectra and material distributions in different parts of the plant were measured by application of sodium 24, bromine 82 and technetium 99m. The investigations led to improved cumeneoxidators and gave useful informations on the catalytic decomposition of the phenolic tar and the hydrogenation process of phenol. It could he shown that the construction of the lactam extractor must he varied and the results of the tracerexperiments made in the distillation unit contributed to a higher quality of the final product.  相似文献   
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5.
Es wird eine radiometrische Bandwaage zur Koksaustragsmengen-Messung in BHT-Kokereien beschrieben. Voranstellend werden einige analytische Ausdrücke zur theoretischen Behandlung dieses Bandwaagentyps mitgeteilt. Die Waage zeichnet sich durch hohe Stabilität der Anzeige, durch die Möglichkeit des routinemäßigen Umsetzens von Meßstelle zu Meßstelle innerhalb kurzer Zeit und durch einen relativ kleinen Wägefehler (Meßunsicherheit ≦ 2,9%) aus. Die Signalaufbereitung innerhalb der Elektronik erfolgt durchgängig digital unter Verwendung eines Rechnerschaltkreises.  相似文献   
6.
Application of hydrocolloids as baking improvers   总被引:1,自引:0,他引:1  
Hydrocolloids (or gums) belong to a group of biopolymers widely used in food technology. In the bakery industry, these compounds help to improve food texture and moisture retention, to retard starch retrogradation, and, finally, to enlarge the overall quality of the products during storage. Since recently, some hydrocolloids are being used due to their polymeric structure as fat replacers to obtain low calorie products and to substitute gluten in the formulation of gluten-free breads. This study describes the applications of some hydrocolloids in the bakery industry. Technological effects of these substances for different types of bakery products are also discussed.  相似文献   
7.
In this paper, we describe the design and fabrication of a dielectrophoresis (DEP)-based cell-positioning and cell-culture device for the construction of cell networks. This device enables both individual cell positioning and cell culture. Titanium electrodes were fabricated by deposition. Furthermore, microchambers and microchannels composed of SU-8, which is a negative photoresist, were used to carry out cell culture and enable cell differentiation. Using our device, N1E-115 cells were individually positioned in the microchambers, and the positioning yield was 45%. After positioning, the cells could be continuously cultured in the microchambers. Furthermore, the cells differentiated, and their neurites extended through the microchannels after cultivation for several days. These results indicate that our device greatly increases the prospects for individual cell positioning and can be used to construct cell networks that have several applications in the medical field, for example, in drug screening.  相似文献   
8.
Optimization of photo-Fenton degradation of copper phthalocyanine blue was achieved by response surface methodology (RSM) constructed with the aid of a sequential injection analysis (SIA) system coupled to a homemade photo-reactor. Highest degradation percentage was obtained at the following conditions [H2O2]/[phthalocyanine] = 7, [H2O2]/[FeSO4] = 10, pH = 2.5, and stopped flow time in the photo reactor = 30 s. The SIA system was designed to prepare a monosegment containing the reagents and sample, to pump it toward the photo-reactor for the specified time and send the products to a flow-through spectrophotometer for monitoring the color reduction of the dye. Changes in parameters such as reagent molar ratios, residence time and pH were made by modifications in the software commanding the SI system, without the need for physical reconfiguration of reagents around the selection valve. The proposed procedure and system fed the statistical program with degradation data for fast construction of response surface plots. After optimization, 97% of the dye was degraded.  相似文献   
9.
浊点萃取技术的应用   总被引:5,自引:0,他引:5  
浊点萃取是近年发展起来的一种新兴的萃取技术。重点阐述了浊点萃取在环境样品、生物样品和食品工业分析中的应用,总结了浊点萃取技术的优点,指出了存在的问题,探讨了该技术的发展前景。  相似文献   
10.
In the nuclear fuel cycle, fluorine is currently not recycled. In this paper, we have examined the possible routes to implement such a cycle. Because UF6 deconversion requires an excess of water, aqueous HF is produced. Two alternatives are then possible: either separate HF from H2O or recycle the HF-H2O in the deconversion process. Alternative UF6 deconversion could also be implemented to resorb the high UF6 inventory.  相似文献   
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