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991.
John W. Tolbert Diana E. Hammerstone Nathaniel Yuchimiuk Jonathan E. Seppala Lesley W. Chow 《大分子材料与工程》2021,306(12):2100442
3D printing is a popular fabrication technique because of its ability to produce complex architectures. Melt-based 3D printing is widely used for thermoplastic polymers like poly(caprolactone) (PCL), poly(lactic acid) (PLA), and poly(lactic-co-glycolic acid) (PLGA) because of their low processing temperatures. However, traditional melt-based techniques require processing temperatures and pressures high enough to achieve continuous flow, limiting the type of polymer that can be printed. Solvent-cast printing (SCP) offers an alternative approach to print a wider range of polymers. Polymers are dissolved in a volatile solvent that evaporates during deposition to produce a solid polymer filament. SCP, therefore, requires optimizing polymer concentration in the ink, print pressure, and print speed to achieve desired print fidelity. Here, capillary flow analysis shows how print pressure affects the process-apparent viscosity of PCL, PLA, and PLGA inks. Ink viscosity is also measured using rheology, which is used to link a specific ink viscosity to a predicted set of print pressure and print speed for all three polymers. These results demonstrate how this approach can be used to accelerate optimization by significantly reducing the number of parameter combinations. This strategy can be applied to other polymers to expand the library of polymers printable with SCP. 相似文献
992.
Kalms Lester Rad Pedram Amini Ali Muhammad Iskander Arsany Göhringer Diana 《Journal of Signal Processing Systems》2021,93(5):513-529
Journal of Signal Processing Systems - In recent years, Convolutional Neural Network CNN have been incorporated in a large number of applications, including multimedia retrieval and image... 相似文献
993.
Ioan Calinescu Ioana Asofiei Adrian Trifan Daniel Ighigeanu Diana Martin 《Chemical Engineering Communications》2017,204(8):965-973
The extraction of essential oils (EOs) and polyphenols from rosemary and thyme has been done using an integrated process: microwave hydro-diffusion and gravity (MHG) for EOs and microwave-assisted extraction (MAE) for polyphenols. The innovative installation based on the MHG principle allows uniform microwave irradiation field due to a mechanical stirring and experiments done at low pressure. The results of quantitative analysis of the EOs extracted by MHG after 10?min were similar with those obtained by traditional methods (conventional hydro-distillation (CHD) and microwave-assisted hydro-distillation (MHD)) after 150 and 105?min, respectively. The specific energy for MHG was 5–15 times lower compared with these classical methods. The MHG extraction of EOs is also an effective method for plant material pretreatment before polyphenol extraction. Total phenolic content increased from 35 to 55?mg GAE/g DM for rosemary and from 23 to 38?mg GAE/g DM for thyme. 相似文献
994.
Lubna Ahmed Ana B. Martin‐Diana Daniel Rico Catherine Barry‐Ryan 《International Journal of Food Science & Technology》2012,47(7):1430-1438
The aim of this study was to investigate the effect of delactosed whey permeate (DWP) treatment on antioxidant and physicochemical properties of strawberries. Fresh strawberries treated with 3% DWP were analysed for different quality, nutritional and microbiological markers during 10 days of storage at 5 °C. The results showed that DWP treatment significantly reduced incidences of decay (70%) and numbers of total aerobic counts (~1.4 Log10 CFU g?1) and yeast and moulds (~1.8 Log10 CFU g?1). DWP treatment also inhibited the loss of firmness (15%) and maintained significantly (P ≤ 0.05) higher levels of vitamin C, total phenols and antioxidant activity of strawberries. Sensory scores confirmed that the DWP‐treated strawberries retained a good appearance and overall quality. The aroma and colour attributes were not reduced during storage. These results suggest that DWP treatment has potential to extend the shelf‐life and maintain the quality of strawberries during storage. 相似文献
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Since December 2009, the European Union Trusted Service Status Lists (TSLs) have been specified and adopted across European Union countries in order to enable the verification of digital signatures with legal values. This paper deals with the exploitation of TSLs in real digital services, other than electronic signatures, that is for certificate validation service. In particular, we used such lists in the service provided by the pan‐European Secure identTities acRoss boRders linKed identity management infrastructure in order to validate X.509 public key certificates. In addition, we propose an XML data structure to be used in conjunction with a TSL, in the form of a Trust Service Association (TrSA) file, to hold trust relationships between different services in a TSL. The TrSA file in conjunction with the TSLs may be used directly by the service providers or users to validate certificates. For the generation of the TSLs, we propose also a tool for automatic generation of the TSLs, named TSLGenerator. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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A Fluorescent Probe for Neural Stem/Progenitor Cells with High Differentiation Capability into Neurons
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Dr. Beomsue Kim Dr. Suihan Feng Dr. Seong‐Wook Yun Dr. Cheryl Leong Dr. Rudrakanta Satapathy Si Yan Diana Wan Prof. Dr. Young‐Tae Chang 《Chembiochem : a European journal of chemical biology》2016,17(22):2118-2122
Selection of a specific neural stem/progenitor cells (NSPCs) has attracted broad attention in regenerative medicine for neurological disorders. Here, we report a fluorescent probe, CDg13, and its application for isolating strong neurogenic NSPCs. In comparison to the NSPCs isolated by other biomarkers, CDg13‐stained NSPCs showed higher capability to differentiate into neurons. Target identification revealed that the fluorescence intensity of the probe within cells is inversely proportional to the expression levels of mouse and human Abcg2 transporters. These findings suggest that low Abcg2 expression is a biomarker for neurogenic NSPCs in mouse brain. Furthermore, CDg13 can be used to isolate Abcg2low cells from heterogeneous cell populations. 相似文献
1000.
Solanum sessiliflorum (mana‐cubiu) antioxidant protective effect toward cholesterol oxidation: Influence of docosahexaenoic acid
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