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11.
Biocatalysis offers a broad spectrum of possible ecological and economic advantages over conventional chemical catalysis processes, e.g., lower energy consumption and high enantio selectivity. The focus of this work is on gas-liquid reactions. These are of great importance in the chemical and biochemical industry and subject of current research since they are often limited by mass transfer or show low selectivity. Different suitable biocatalytically gas-liquid reaction systems were tested in capillary reactor designs in order to obtain information about the interaction between reaction and fluid mechanics. Furthermore, an optical measuring method was established. The experiments were performed in batch mode in a glass beaker with a flow cuvette for UV/Vis measurement of product concentration. 相似文献
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Inga Miina Elise Sipeniece Magdalena Rudziska Anna Grygier Monika Radzimirska‐Graczyk Edte Kaufmane Dalija Seglia Gunrs Lcis Pawe Grna 《European Journal of Lipid Science and Technology》2020,122(4)
Tocopherols, phytosterols, carotenoids, and squalene are present in mature seeds of Japanese quince. Yet, little is known about the relationship between these compounds and oil yield during fruit and seed development. The profile change of lipophilic compounds during fruit and seed development in Japanese quince cultivars “Darius,” “Rondo,” and “Rasa” is investigated. It is shown here that during fruit and seed development, there is a significant reduction, three‐ to over tenfold, in the concentration of minor bioactive compounds in seed oil. It is recorded that delay between synthesis of tocopherols and oil in Japanese quince seeds during the fruit development results in a logarithmic relationship between the oil content and tocopherols concentration in the seed oil (R2 = 0.980). Similar trends are observed between oil yield and phytosterols, and carotenoids (R2 = 0.927 and R2 = 0.959, respectively). The profile of fatty acids during the development of the seeds significantly is changed. The reduction of linoleic, palmitic, and gondoic acids levels and increment of oleic acid is noted. The oil content, profile of fatty acids, and concentration of bioactive compounds in all three genotypes of Japanese quince do not change significantly statistically during the last month of fruit development. Practical Applications: Some fruits are harvested at different degrees of maturity mainly due to a logistic issue and uneven ripening of fruits, which affects the chemical composition of whole fruit including seeds. Therefore, it would be good to know how the chemical composition is changing in plant material during development especially in the last month before harvest. Production of Japanese quince continues to rise year to year and with it the volume of generated by‐products such as seeds. This study demonstrates how it changes the oil content, profile of fatty acid, and concentration of tocopherols, squalene, phytosterols, and carotenoids in the seeds and seed oil of three Japanese quince cultivars “Rondo,” “Darius,” and “Rasa” during plant development. The provided information can be very useful for the manufactories oriented on the processing of by‐products, mainly seeds, generated by other branches of industry, for instance, fruit‐processing. 相似文献
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Chemical Composition of Seed Oils Recovered from Different Pear (Pyrus communis L.) Cultivars
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![点击此处可从《Journal of the American Oil Chemists](/ch/ext_images/free.gif)
Paweł Górnaś Magdalena Rudzińska Marianna Raczyk Inga Mišina Arianne Soliven Dalija Segliņa 《Journal of the American Oil Chemists' Society》2016,93(2):267-274
Lipophilic bioactive compounds in oils recovered from the seeds of eight pear (Pyrus communis L.) cultivars were studied. Oil yield in pear seeds ranged between 16.3 and 31.5 % (w/w) dw. The main fatty acids were palmitic acid (6.13–8.52 %), oleic acid (27.39–38.17 %) and linoleic acid (50.73–63.78 %), all three representing 96–99 % of the total detected fatty acids. The range of total tocochromanols was between 120.5 and 216.1 mg/100 g of oil. Independent of the cultivar, the γ‐tocopherol was the main tocochromanol and constituted approximately 88 %. The contents of the carotenoids and squalene were between 0.69–2.99 and 25.5–40.8 mg/100 g of oil, respectively. The β‐sitosterol constituted 83.4–87.6 % of total sterols contents, which ranged between 276.4 and 600.1 mg/100 g of oil. Three significant correlations were found between oil yield and total contents of sterols (r = ?0.893), tocochromanols (r = ?0.955) and carotenoids (r = ?0.685) in pear seed oils. 相似文献
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Computerized displays of continuously acquired audience response measures have become an increasingly common component in television, particularly in political campaign media coverage. However, the effect of such presentations on consumer’s perceptions of both the presenters and their messages remain unclear. To address this concern, simulated computerized continuous response measurement (CRM) graphics were overlaid onto apolitical video content to produce three (negative, neutral, positive) experimental manipulations. The findings revealed considerable symmetry between the valence of the CRM graphics and research participant responses. Evaluations of the presenter and message were significantly more negative following negative CRM graphic manipulation exposure (compared against the neutral and positive conditions) suggesting that CRM graphics can be a powerful device for influencing viewers’ judgments. 相似文献
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The design and results of a cyclic hydraulic fracturing experiment performed to enhance the productivity of the geothermal research well at Groß Schönebeck (Germany) are presented. The stimulation carried out in the low-permeability volcanics of the Lower Rotliegend (Lower Permian) included alternating stages with cyclic changes of low and high flow rates with up to 150 L/s over six days in conjunction with the addition of quartz sand to support fracture opening. There was rapid water level increase in an adjacent well due to the stimulation (i.e. water injection). The subsequent production test showed the success of the fracture treatment, with the overall productivity of the treated well being increased by a factor of four. 相似文献
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Branko Deljanin Dusan Simic Alexander Zaitsev John Chapman Inga Dobrinets Annette Widemann Nicholas Del Re Tara Middleton Elena Deljanin Andrea De Stefano 《Diamond and Related Materials》2008,17(7-10):1169-1178
One of the commercial challenges today in the gem industry is to quickly identify the origin of color in pink diamonds — natural, treated and synthetic by use of standard and advanced gemological instruments.An analytical technique that is used by many gem labs involves UV fluorescence. The principle factors in the technique are the excitation wavelengths and the emission spectra. No systematic study of fluorescence of pink natural diamonds, pink treated and pink synthetic diamonds has been undertaken. This study is mainly focused on using fluorescence techniques to characterize pink diamonds and to compile a reference library of emission spectra. Longwave (LW) and shortwave (SW) fluorescence of 365, 254 and 220 nm illumination were used in a custom built microscope with a fluorescence camera to record images and a spectrometer to record spectral data with which to establish a correlation with the cause of color.Other advanced instruments (CL imaging, UV–VIS–NIR, FTIR, PL spectroscopy and electrical conductance) were used to establish additional criteria for distinguishing natural, treated and synthetic pink diamonds and to find a correlation with the “EGL USA CIS (Cross-reference Identification System) fluorescence method”. 相似文献