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311.
含氟侧链在自交联含氟乳胶膜上的排列 总被引:2,自引:0,他引:2
借助JC2000A静态接触角测量仪和XPS对所制备的自交联含氟乳液涂膜进行表征及分析, 分别利用实验法和基团贡献法计算涂膜的表面自由能, 探讨含氟侧链在自交联含氟乳胶膜的排列. 结果表明, 增加含氟单体的用量, 可以降低含氟聚合物涂膜的表面自由能, 但当含氟单体用量超过20.3%时, 涂膜的表面自由能的变化不大, 含氟乳胶膜具有良好的自我恢复性能. 进一步的研究结果表明, 含氟聚合物乳液成膜后含氟侧链在涂膜表面的排列是一种无规则排列. 相似文献
312.
Iron is a key micronutrient essential for many biological events. While iron deficiency can lead to anemia, supplementation with oral iron often ends up with enteral iron overload, a critical gastrointestinal (GI) burden linked to the increased risk of dysbiosis, infections and often associated with colorectal cancer. Iron chelation therapy is clinically used to reduce pathological systemic iron overload by established low molecular weight iron chelators. As drawbacks, these drugs present low pharmacokinetic profiles and several toxicities, leading to relatively high rates of adverse effects. To overcome these issues, the prevention of iron accumulation in the GI tract by non-absorbable iron binding polymers could represent an alternative still underexploited approach. Here, we present the development of a series of insoluble polymeric Fe(III) chelators. These innovative compounds have been obtained by the conjugation of 3-hydroxypyridin-4-one Fe(III) chelating moiety with branched Polyethyleneimine (PEI) and Carboxymethyl cellulose (CMC). In vitro binding studies indicated that the Fe(III) chelating capacity depends on the nature of the polymer. In particular, PEI derivatives possess higher selectivity toward Fe(III) in simulated intestinal fluid preserving the integrity of intestinal enterocytes, representing thus promising compounds in the development of iron chelators. 相似文献
313.
Pekka J. Korhonen Pekka Malo Tommi Pajala Niklas Ravaja Outi Somervuori Jyrki Wallenius 《European Journal of Operational Research》2018,264(1):270-279
We show that contextual variables in a Multiple Criteria Decision Making task influence choice quality. Based on an experiment we investigate the effects of product type, emotional attachment, and the amount and structure of information provided. We measured choice quality with nondominance, which is a desirable property of good choices. Regarding the product type effect, we distinguish between hedonic products that primarily are desirable due to affect, and utilitarian products, which are desirable because they are useful. When subjects with high emotional attachment make choices with hedonic products, they make fewer dominated choices than with utilitarian products. Further, we show that information overload is a relevant phenomenon in MCDM experiments. However, what matters is the quality of information, not just the quantity. When we add information that does not change the dominance relations between products, choice quality is not degraded. 相似文献
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317.
现代高校学报编辑应具备的素质与能力 总被引:1,自引:0,他引:1
朱君华 《宁波大学学报(理工版)》2004,17(2):236-239
高校学报编辑的素质与能力问题,前人多有论及,现代社会的发展对编辑素质与能力。提出了更高的要求.通过对素质和能力的认识阐述,提出现代高校学报编辑的素质要求和应具备的能力. 相似文献
318.
The possibility of improving the discrimination capability (DC) in color pattern recognition is analyzed. In each channel, red, green and blue (R, G, B), a region of support is designed to improve the behavior of the Phase Only Filter matched to the corresponding component of the target. The procedure of optimization is based on the analytical expressions which give the DC in R, G, B channels, for real valued input scenes. Computer simulation results are presented and discussed. 相似文献
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Hualong Liu Yiqiang Li Junwei Hou Yishan Liu 《Journal of Dispersion Science and Technology》2016,37(1):89-96
As one of the important mechanisms of EOR for SP binary flooding, emulsification attracts much attention of researchers. But there have not yet unified methods or clear understandings of evaluation of the emulsion function on flooding system and emulsification's impact on enhanced oil recovery. A comprehensive evaluation method of emulsifying properties is established in this paper for the first time. It characterizes the emulsifying properties of different flooding system by using the emulsifying integrated index, and examines the corresponding core flooding results of different emulsifying properties. Results of Berea core test show that the flooding system runs better with a higher emulsifying composite index in cores whose permeability is 300 ~ 400 mD. When emulsifying integrated index increases from 23.9% to 80.2%, the corresponding oil displacement efficiency reaches 12%. When emulsifying integrated index is under the medium level of 50% or less, the SP flooding system efficiency increases rapidly with the index changes, then increases slowly. The influencing rule of emulsification of SP binary flooding is obtained in this paper, which is important to optimize the formulation of SP binary flooding system, provide an important basis and technical support for the design of field experiments and SP flooding promotion. 相似文献