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581.
The design of industrial feed line sections and the selection of appropriate inlet devices requires knowledge about the two-phase flow morphology and phase fractions in order to reduce costly overdesign. Since experimental data for two-phase pipe flows at industrial scale are hardly available, current prediction methods are subject to high unertainities. In this study, horizontal two-phase flow morphologies for different industrial feed line sections were studied using wire-mesh sensors at multiple locations along the pipe. The obtained phase fraction data are compared with correlations.  相似文献   
582.
Wire mesh flooding point measurements at low surface tension < 10 mN m−1 were conducted using a refrigerant as model fluid. A new method for the calculation of wire mesh capacity was developed based on experimental data from literature and data from this study. In comparison to the well-known and widely adapted K-value method given in the Gas Processors Suppliers Association (GPSA) Engineering Databook and various other sources, the new method yields 3–38 % reduced wire mesh cross sections for fluid systems at pressures above 20 bar(a) while retaining an inherent safety margin.  相似文献   
583.
584.
Potato is an important staple food crop in both developed and developing countries. However, potato plants are susceptible to several economically important viruses that reduce yields by up to 50% and affect tuber quality. One of the major threats is corky ringspot, which is a tuber necrosis caused by tobacco rattle virus (TRV). The appearance of corky ringspot symptoms on tubers prior to commercialization results in ≈ 45% of the tubers being downgraded in quality and value, while ≈ 55% are declared unsaleable. To improve current disease management practices, we have developed simple diagnostic methods for the reliable detection of TRV without RNA purification, involving minimalized sample handling (mini), subsequent improved colorimetric loop-mediated isothermal amplification (LAMP), and final verification by lateral-flow dipstick (LFD) analysis. Having optimized the mini-LAMP-LFD approach for the sensitive and specific detection of TRV, we confirmed the reliability and robustness of this approach by the simultaneous detection of TRV and other harmful viruses in duplex LAMP reactions. Therefore, our new approach offers breeders, producers, and farmers an inexpensive and efficient new platform for disease management in potato breeding and cultivation.  相似文献   
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586.
The objective of this research was to investigate the effects of temperature (40–70 °C), frequency (37 and 80 kHz) and ultrasonic operation mode (normal, pulse and sweep), and their interactions on the recovery of phenolic compounds and antioxidants present in pomegranate peel using ultrasound-assisted extraction. The content of individual phenolic compounds, total phenolic compounds (TPC), antioxidant capacity (AC) and total extract yield (X0) were analysed. Significant effects were observed between some sources of variation in recovery of individual compounds at TPC and X0, and no significant effect was observed for AC. The process and conditions studied shown to be interesting to extract antioxidants, since a high antioxidant capacity was verified in the extracts. Temperatures around 50–60 °C, using 37 kHz frequency, and normal or pulse modes were the conditions that provided better yields of phenolic compounds and X0. Regarding AC, the best condition observed was at 70 °C, 80 kHz frequency and continuous mode.  相似文献   
587.
588.
Fixation of β-Cyclodextrinderivatives on Polyester Fibres . Syntheses of derivatives of β-cyclodextrin are described which aimed at a partial substitution of OH-groups by hydrophobic moieties. According to such substitution it can be envisaged that those derivatives are applicable to polyester fabric treatment by conventional dispersion dyeing methods. By applying such textile finishing agents it can be expected to impart hydrophilic properties to the fabric due to unsubstituted OH-groups of the cyclodextrin but still remaining complexation ability due to the cyclodextrin inner torus. The success of anchoring of the derivatives onto polyester and methods for evidence of cyclodextrin derivatives on the polyester surface (iodine incorporation, fluorescence activity of dyestuffs included, FT-IR-spectroscopy) are given.  相似文献   
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