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991.
Maria Vidal-Rohr James S. Wolffsohn Leon N. Davies Alejandro Cerviño 《Contact lens & anterior eye》2018,41(1):117-121
Aim
Retrospective analysis of different contact lens wearing groups suggests lens surface lubricity is the main factor influencing contact lens comfort. However, the examined commercially available contact lenses differ in material and design as well as surface properties. Hence this study isolates the contribution of lens surface properties using an ultra-thin coating technology.Methods
Nineteen habitual contact lens wearers (21.6 ± 1.7years) wore formofilcon B soft monthly disposable contact lenses with and without coating technology modified surface properties for a month each in a randomised double-masked cross-over study.Objective non-invasive
breakup time (NIKBUT), NIKBUT average and ocular redness (Jenvis grading scale) were evaluated (Keratograph 5M) after 1 week and 1 month of wear. Symptoms were assessed using the Contact Lens Dry Eye Questionnaire (CLDEQ-8); perceived vision quality and subjective lens comfort at insertion, mid-day and end of the day were rated with four Visual Analog Scales.Results
Perceived visual quality (F = 5.049,p = 0.037), contact lens dry eye symptoms (F = 14.408,p = 0.001) and subjective lens comfort (F = 28.447,p < 0.001) were better for coated compared to uncoated lenses. The surface coating postponed the lens dewetting (F = 8.518,p = 0.009) and increased the pre-lens tear film stability (F = 5.626,p = 0.029), but bulbar (F = 0.340,p = 0.567) and limbal (F = 0.110,p = 0.744) redness were similar for both contact lenses. No parameter changed significantly between a weeks’ and months’ wear (p > 0.05). Lens surface wettability and ocular redness were not correlated to changes in symptoms (p > 0.05).Conclusion
As previously hypothesised, enhancing the physical surface properties of a soft contact lens improves subjectively rated wearer comfort, which, in turn, should result in reduced contact lens discontinuation. 相似文献992.
Jonathan Douglas Major Leon Bowen Robert Treharne Ken Durose 《Progress in Photovoltaics: Research and Applications》2014,22(10):1096-1104
A major limitation of the cross‐section electron beam‐induced current method—the use of roughly fractured surfaces to provide the cross‐section—has been overcome with the use of focused ion beam microscope sample preparation. Using this method, it was possible to undertake a study of the relation between junction position and the corresponding external quantum efficiency (EQE) curves. For the case of cadmium telluride (CdTe) cells, it was demonstrated that the EQE curve shape that indicates a buried CdTe homojunction only arises if the junction is buried by more than 0.9 µm from the heterointerface. This highlights the limitations of interpreting EQE curve shape to determine junction position. It was also shown that extended postgrowth annealing degrades the cadmium sulfide by Kirkendall voiding, and this leads to efficiency loss. © 2014 The Authors. Progress in Photovoltaics: Research and Applications published by John Wiley & Sons, Ltd. 相似文献
993.
Chun Lu Jianzhi Hu Ja Hun Kwak Zhenguo Yang Ruiming Ren Tippawan Markmaitree Leon L. Shaw 《Journal of power sources》2007,170(2):419-424
To gain insight into the effects of mechanical activation (MA) on the hydrogen desorption of the lithium amide (LiNH2) and lithium hydride (LiH) mixture, LiNH2 and LiH + LiNH2 were mechanically activated by high-energy ball milling. The formed products were studied with in situ 1H and 6Li nuclear magic angle spinning (MAS) magnetic resonance (NMR) spectroscopy from ambient temperature to 180 °C. Up-field chemical shift was observed in 6Li MAS NMR spectra with increased milling time, indicating that average local electronic structure around Li nuclei was modified during MA. 1H MAS NMR was used to dynamically probe ammonia release from the activated LiNH2 at temperature as low as 50 °C. In the case of activated LiH + LiNH2 mixtures, the 1H MAS NMR results implied that MA enhanced the dehydrogenation reaction of LiNH2 + LiH = Li2NH + H2. 相似文献
994.
Dr. Ana Malvis Romero Felix Brozio Sinah Kammler Dr. Christin Burkhardt Leon Baruth Prof. Dr. Martin Kaltschmitt Prof. Dr. Garabed Antranikian Prof. Dr. Andreas Liese 《化学,工程师,技术》2023,95(4):549-556
Beach wrack constitutes an unutilized, abundant renewable source of marine macro algae being rich in valuable biopolymers. This work investigates the revalorization of the brown algae Fucus vesiculosus collected from beach wrack as a source of alginate, the main polysaccharide in brown algae which constitutes a potential ingredient for the development of biopolymer films. Enzyme-assisted extraction has been investigated for cell disruption with commercial cellulase blends and proteases. The effect of enzyme type, enzyme activity, and extraction time on alginate yields, molecular weight distribution, functional groups, and purity has been studied. 相似文献
995.
Dr. Marco Gärtler Dr. Martin Hollender Dr. Benjamin Klöpper Sylvia Maczey Dr. Ruomu Tan Dr. Chen Song Dr. Franz David Bähner Prof. Dr.-Ing. Stefan Krämer Gregor Just Dr. Valentin Khaydarov Prof. Dr.-Ing. Leon Urbas Rebecca Gedda 《化学,工程师,技术》2023,95(7):989-1002
Specialty and fine chemicals are often manufactured in multipurpose batch production plants. Compared to continuous production, these plants offer increased flexibility at the cost of operational complexity. A recipe defines the sequence and process parameters of different batch phases that are needed to transform raw materials into the desired product. In some plants detailed information about the executed recipe is not always captured by data acquisition systems. Knowledge of these phases is essential for optimizing quality and throughput. State-of-the-art data-driven machine learning techniques can recognize recurrent patterns in noisy time series data, enabling automatic labeling of batch phases based on widely available sensor data. In this review paper, we provide an overview of several machine learning approaches that can be used in an industrial setting. 相似文献
996.
Marian Matzke Ekaterina Ranft Leon Dominkovic Prof. Dr. Mathias Ulbricht Prof. Dr.-Ing. Heyko Jürgen Schultz 《化学,工程师,技术》2023,95(10):1592-1602
In this study, the flow fields of two-stage impellers, consisting of combinations of different impeller types on one shaft, are investigated using stereo particle image velocimetry. Based on the results of torque measurements, diameters for different impellers are determined in order to achieve matching power input of the individual turbines. When implemented adequately, both selected impellers are able to contribute their respective characteristics, resulting in flow fields that differ significantly from those induced by single-stage impellers as well as two-stage setups consisting of identical impellers. 相似文献
997.
Harvey B Edrington TS Kubena LF Rottinghaus GE Turk JR Genovese KJ Ziprin RL Nisbet DJ 《Journal of food protection》2002,65(2):373-377
The effects of fumonisin B1 (FB1) from Fasarium verticillioides culture material and moniliformin from Fusarum fujikuroi culture material on growing barrows were evaluated. Four groups of six barrows (three replicates of two each; mean body weight, 11.1 kg) were fed diets containing 0 mg of FB1 and 0 mg of moniliformin per kg of feed (control), 100 mg of FB1 per kg of feed, 100 mg of moniliformin per kg of feed, and 100 mg of FB1 plus 100 mg of moniliformin per kg of feed. Barrows were fed these diets for 28 days. Body weight gain, feed efficiency, serum biochemical analytes, and hematological values were adversely affected by the FB1 and the FB1-plus-moniliformin diets. The moniliformin diet decreased body weight gain. Two barrows in the moniliformin diet group died, and two barrows in the FB1-plus-moniliformin diet group died. All deaths occurred during the first 6 days of the study. Mild to moderate lesions were observed microscopically in heart and lung tissues of the groups fed moniliformin and FB1 plus moniliformin and in liver tissues of the groups fed FB1 and FB1 plus moniliformin. Except for the acute mortality associated with the two diets containing moniliformin. clinical disease induced by the combined feeding of these two mycotoxins appears to be additive or less than additive and due primarily to the toxic expression of FB1. 相似文献
998.
999.
Heunis T Bshena O Klumperman B Dicks L 《International journal of molecular sciences》2011,12(4):2158-2173
Plantaricin 423, produced by Lactobacillus plantarum, and bacteriocin ST4SA produced by Enterococcus mundtii, were electrospun into nanofibers prepared from different combinations of poly(d,l-lactide) (PDLLA) and poly(ethylene oxide) (PEO) dissolved in N,N-dimethylformamide (DMF). Both peptides were released from the nanofibers with a high initial burst and retained 88% of their original antimicrobial activity at 37 °C. Nanofibers have the potential to serve as carrier matrix for bacteriocins and open a new field in developing controlled antimicrobial delivery systems for various applications. 相似文献
1000.
Gnonlonfin BG Gbaguidi F Gbenou JD Sanni A Brimer L 《Journal of the science of food and agriculture》2011,91(13):2344-2347
BACKGROUND: The use of the root crop cassava (Manihot esculenta Crantz) is constrained by its rapid deterioration after harvesting. Chemical and spectroscopic examination earlier revealed the accumulation of the four hydroxycoumarins esculetin, esculin, scopolin and scopoletin derived from the phenylpropanoid pathway, during the time course of postharvest deterioration. In this investigation the scopoletin level in parenchymal samples of four cassava cultivars used in Benin, i.e. Kpaki kpika, Kpaki soan, Logoguesse kotorou and BEN 86052, was investigated by high‐performance liquid chromatography (HPLC). RESULTS: Presence was shown in all four varieties with a mean in fresh roots between 4.1 and 11.1 mg kg?1 dry weight. A strong increase in the content of scopoletin was noticed after a peeling and drying process (6 days) for chip production, the mean content reaching 242.5 mg kg?1 dry weight in the cultivar BEN 86052. After 3 months of storage this had decreased to 0.7 mg kg?1 dry weight. CONCLUSION: Strong accumulation of scopoletin in cassava roots used for chip production in Benin is followed by a decrease in its concentration. Copyright © 2011 Society of Chemical Industry 相似文献