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排序方式: 共有1894条查询结果,搜索用时 15 毫秒
991.
Fouling on food contact surfaces (e.g. heat exchangers, work tables, conveyors) during food processing has a significant impact on operating efficiency and can promote biofilm development. Processing raw milk on plate heat exchangers results in significant fouling of proteins as well as minerals, and is exacerbated by the wall heating effect. The surface of 316L stainless steel heat exchanger plates was modified to resist fouling during food processing. An electroless nickel plating process was used to co-deposit fluorinated nanoparticles onto 316L stainless steel. The ability to resist fouling was demonstrated on a pilot plant scale plate heat exchanger. The fluorinated nanoparticle modified steel reduced surface energy from 41.4 to 24.7 mN/m, and reduced foulant accumulation by 97%. The anti-fouling coating was demonstrated to improve heat transfer efficiency. Repeatability studies were performed and confirmed that the EN-PTFE surface coating maintained its anti-fouling properties through 10 independent processing runs. Co-deposition of fluorinated particles during electroless nickel plating represents an effective and commercially scalable method to prepare anti-fouling coatings on stainless steel. 相似文献
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993.
The dependence to temperature of the rebound of a solid polymer ball on a rigid slab is investigated. An acrylate polymer ball is brought to a wide range of temperatures, covering its glass to rubbery transition, and let fall on a granite slab while the coefficient of restitution, duration of contact, and force history are measured experimentally. The ball fabrication is controlled in the lab, allowing the mechanical characterization of the material by classic dynamic mechanical analysis. Finite element simulations of the rebound at various temperatures are run, considering the material as viscoelastic and as satisfying a WLF equation for its time–temperature superposition property. A comparison between the experiments and the simulations shows the strong link between viscoelasticity and time–temperature superposition properties of the material and the bounce characteristics of the ball. 相似文献
994.
Narayanan K. Lakshmi Krishnan R. Santhana Son Le Hoang Tung Nguyen Thanh Julie E. Golden Robinson Y. Harold Kumar Raghvendra Gerogiannis Vassilis C. 《Multimedia Tools and Applications》2022,81(3):3297-3325
Multimedia Tools and Applications - Robotics is one of the most emerging technologies today, and are used in a variety of applications, ranging from complex rocket technology to monitoring of crops... 相似文献
995.
Julie Pepin Eric Lainé Jean-Claude Grandidier Sylvie Castagnet Pierre Blanc-vannet Philippe Papin Mathilde Weber 《International Journal of Hydrogen Energy》2018,43(33):16386-16399
Depressurization tests at a laboratory scale, coupled with numerical modelling, are used to determine the key parameters responsible for the polymeric liner collapse in hyperbaric type IV hydrogen storage vessels. X-ray tomography allows to determine the damages suffered by the sample during the depressurization step. Results show that the differential pressure induced during the depressurization step between the liner/composite interface and the free surface of the liner is the main factor responsible for the collapse of the liner. For a given temperature, this pressure gradient can be modified by changing the maximum H2 pressure, the emptying rate or by adding a residual pressure plateau. Temperature is also of prime importance by influencing the yield point of the liner, the interface resistance and the amount of gas dissolved into the vessel. Thus, increasing temperature also increases the risk of liner collapse for the same gas exposure conditions. 相似文献
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997.
Chien-Ning Hsu Julie Y. H. Chan Kay L. H. Wu Hong-Ren Yu Wei-Chia Lee Chih-Yao Hou You-Lin Tain 《International journal of molecular sciences》2021,22(5)
Gut microbiota-derived metabolites, in particular short chain fatty acids (SCFAs) and their receptors, are linked to hypertension. Fructose and antibiotics are commonly used worldwide, and they have a negative impact on the gut microbiota. Our previous study revealed that maternal high-fructose (HF) diet-induced hypertension in adult offspring is relevant to altered gut microbiome and its metabolites. We, therefore, intended to examine whether minocycline administration during pregnancy and lactation may further affect blood pressure (BP) programmed by maternal HF intake via mediating gut microbiota and SCFAs. Pregnant Sprague-Dawley rats received a normal diet or diet containing 60% fructose throughout pregnancy and lactation periods. Additionally, pregnant dams received minocycline (50 mg/kg/day) via oral gavage or a vehicle during pregnancy and lactation periods. Four groups of male offspring were studied (n = 8 per group): normal diet (ND), high-fructose diet (HF), normal diet + minocycline (NDM), and HF + minocycline (HFM). Male offspring were killed at 12 weeks of age. We observed that the HF diet and minocycline administration, both individually and together, causes the elevation of BP in adult male offspring, while there is no synergistic effect between them. Four groups displayed distinct enterotypes. Minocycline treatment leads to an increase in the F/B ratio, but decreased abundance of genera Lactobacillus, Ruminococcus, and Odoribacter. Additionally, minocycline treatment decreases plasma acetic acid and butyric acid levels. Hypertension programmed by maternal HF diet plus minocycline exposure is related to the increased expression of several SCFA receptors. Moreover, minocycline- and HF-induced hypertension, individually or together, is associated with the aberrant activation of the renin–angiotensin system (RAS). Conclusively, our results provide a new insight into the support of gut microbiota and its metabolite SCAFs in the developmental programming of hypertension and cast new light on the role of RAS in this process, which will help prevent hypertension programmed by maternal high-fructose and antibiotic exposure. 相似文献
998.
Bertels Julie; Kolinsky Régine; Pietrons Elise; Morais José 《Canadian Metallurgical Quarterly》2011,11(1):29
Using an auditory adaptation of the emotional and taboo Stroop tasks, the authors compared the effects of negative and taboo spoken words in mixed and blocked designs. Both types of words elicited carryover effects with mixed presentations and interference with blocked presentations, suggesting similar long-lasting attentional effects. Both were also relatively resilient to the long-lasting influence of the preceding emotional word. Hence, contrary to what has been assumed (Schmidt & Saari, 2007), negative and taboo words do not seem to differ in terms of the temporal dynamics of the interdimensional shifting, at least in the auditory modality. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
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1000.