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11.
Qi Xiao Xinyao Dong Xiumei Yin Hong Wang Hua Zhong Mingming Xing Ying Tian Yao Fu Bin Dong Xixian Luo 《Journal of the American Ceramic Society》2021,104(3):1415-1423
Multicolor upconversion luminescence materials show significantly applications in materials science. In this paper, the novel Yb3+-sensitized Na3La(VO4)2 upconversion luminescence crystals are synthesized by the solid-state reaction method. Three primary colors upconversion luminescence are successfully achieved in Na3La(VO4)2:Yb3+,Tm3+, Na3La(VO4)2:Yb3+,Er3+, and Na3La(VO4)2:Yb3+,Ho3+ crystals excited by the single 980 nm LD. Multicolor upconversion luminescence can be obtained by simply adjusting the combination ratios of these three samples. Luminescence mechanisms of the Yb3+-sensitized system are discussed in detail. In the Na3La(VO4)2 host material, the Yb3+/Ho3+ codoped system exhibits unusual red upconversion luminescence based on the short decay time of Ho3+ ion 5I6 level, which provides the possibility of three primary color luminescence under 980 nm excitation. 相似文献
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13.
Zhiwei Qiao Lifeng Li Shuhua Li Hong Liang Jian Zhou Randall Q. Snurr 《American Institute of Chemical Engineers》2021,67(10):e17352
Computational screening was employed to calculate the enantioseparation capabilities of 45 functionalized homochiral metal–organic frameworks (FHMOFs), and machine learning (ML) and molecular fingerprint (MF) techniques were used to find new FHMOFs with high performance. With increasing temperature, the enantioselectivities for (R,S)-1,3-dimethyl-1,2-propadiene are improved. The “glove effect” in the chiral pockets was proposed to explain the correlations between the steric effect of functional groups and performance of FHMOFs. Moreover, the neighborhood component analysis and RDKit/MACCS MFs show the highest predictive effect on enantioselectivities among the four ML classification algorithms with nine MFs that were tested. Based on the importance of MF, 85 new FHMOFs were designed, and a newly designed FHMOF, NO2-NHOH-FHMOF, with high similarity to the optimal MFs achieved improved chiral separation performance, with enantioselectivities of 85%. The design principles and new chiral pockets obtained by ML and MFs could facilitate the development of new materials for chiral separation. 相似文献
14.
ABO亚型会导致红细胞凝集反应出现正反定型不符,目前实验室针对ABO亚型的鉴定主要使用PCR-SSP,该技术存在假阳性、通量低等缺点,因此开发可准确鉴定ABO血型亚型的方法迫在眉睫.为解决该问题,作者构建了一种基于SNaPshot技术鉴定ABO血型亚型的方法,该方法通过检测ABO基因第六外显子(261、297)、第七外显子(425、467、695、700、803、871、1054)上的9个SNP位点,并根据它们的组合鉴别14种不同的ABO等位基因.作者还提取50个外周血样本的基因组DNA,运用SNaPshot技术成功地对所有样本进行分型,共检出10种等位基因,分别为A101、A102、B01、B305、BW11、O101、O102、O02、B(A)02和CisAB.经验证,该方法适用于ABO血型亚型的分型. 相似文献
15.
为分析地表径流速度对城市内涝的影响,采用一维地下排水管网与二维城区地形的动态耦合模型,选取大连市某排水区块作为研究区域,设置4种地表径流速度10种设计降雨场景,模拟分析在不同重现期设计降雨及不同地表径流速度下研究区的内涝积水特性。结果表明:随着地表径流速度降低,管道排水压力变小,管道排水达标率最高可提升48.05%,且降雨重现期越短,地表径流流速对管道排水压力的削减效果越明显;地表径流流速对检查井溢流量影响显著,随着地表径流速度降低,检查井溢流量峰值最高可减小2 750 m~3,峰现时间最长可滞后56 min,同时随着降雨重现期增长,地表径流流速对检查井溢流量的削减效果减弱;研究区低、高风险区淹没面积随地表径流速度降低,最高可分别减小1.64万、8.37万m~2,但中风险区淹没面积变化反复。 相似文献
16.
Applied Composite Materials - The objectives of this experimental study are to develop impact-resistant three-dimensional (3D) woven textile-reinforced composites as well as to clarify the... 相似文献
17.
Anisse Pereira Hong C. Lee Robert Lammert Jr. Cailyn Wolberg Jr. Danyi Ma Chad Immoos Federico Casassa Iksoon Kang 《International Journal of Food Science & Technology》2022,57(3):1814-1823
This study was conducted to evaluate the effect of red-wine grape pomaces on the quality and sensory attributes of beef hamburger patties. Both phenolic content and antioxidant activity were assessed using Syrah, Merlot and Cabernet Sauvignon pomaces. Following the assessment, hamburger patties were prepared with Merlot pomace at 0%, 2% and 4% for the patty quality and sensory attributes. Grape seeds possessed significantly higher phenolics and antioxidant activities over the seedless pomace (P < 0.05), whereas no significant difference was found for phenolics and antioxidant activities within the seeds and seedless pomaces. The patty pH decreased as the pomace was added for 2% and 4%. Colour values (L*, a* and b*) of patties lowered as the pomace was added. Allo-Kramer shear force and hardness values increased while cooking yield decreased (P < 0.05) with the addition of pomace. No significant difference between control and Merlot patties was found for flavour, juiciness and colour, whereas lower sensory attributes were observed for texture, taste and overall acceptability. It is observed that the addition of fermented red-wine grape pomace provides hamburger patties with health promoting factors such as antioxidant and other functional components, but it also provided darker, sourer and lower cooking yield. 相似文献
18.
Cuiping Yi Lan Xie Zhongfu Cao Ke Quan Hong Zhu Jieyao Yuan 《International Journal of Food Science & Technology》2022,57(8):5048-5056
Brown rice noodles (RN) are typical whole-grain products with health benefits. This study investigated the effects of rice bran fermented with Lactobacillus plantarum on palatability, volatile profiles, and antioxidant activity of brown RN. Three kinds of RN, including RN, brown RN (BRN), and bran fermented RN (BFRN), were involved in this study. The results indicated that bran fermentation reduced the cooking loss of BFRN and improved the elongation and the sensory attributes of brown RN. After fermentation, aldehydes were significantly decreased while alcohols increased, and more pleasant flavours were shown in BFRN. Fermentation increased the content of free phenolics and decreased the content of bound phenolics. Among the four major phenolics detected in this study, ferulic acid was the most abundant one in all three RN samples. The DPPH radical scavenging activity and the ferric reducing antioxidant power of free phenolics in BFRN increased significantly compared to BRN. This study proved that rice bran fermentation is an effective approach to improve palatability, enrich the flavour as well as enhance the antioxidant activity of brown RN, which may facilitate the development of processing technology for brown RN. 相似文献
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20.
Kothandaraman Mohanaprasad Law Zijian Ezra Morris A. G. Pua Chang Hong Rajasekaran Uma 《Water Resources Management》2022,36(6):1973-1989
Water Resources Management - The localization of the leaks is estimated using the time difference method in the past decade. Generalized and Basic Cross-correlation techniques are frequently... 相似文献