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991.
Agustín Martínez-Ruvalcaba Fausto Becerra-Bracamontes Juan C. Sánchez-Díaz Alejandro González-Álvarez 《Polymer Bulletin》2009,62(4):539-548
This work presents the synthesis of polyacrylamide-gelatin (PAM-G) semi-interpenetrating hydrogels, as well as the study of
the swelling capacity of this material at different pH’s, and we report its Young modulus. The hydrogels were crosslinked
with N,N′-methylenebisacrylamide and synthesized at different acrylamide/gelatin weight relationship. It was observed that the swelling
capacity of the hydrogels increases when the gelatin concentration is increased; while the Young modulus (at the swelling
equilibrium) decreases lightly. Therefore, the gelatin has a small effect in the Young modulus, unlike its influence in the
swelling ability. The swelling experiments reveal that the PAM-G hydrogels increase its swelling capacity in alkaline mediums
because the presence of the hydrophobic functional groups (mainly COO−) in the gelatin structure. 相似文献
992.
Chinese yam polysaccharide enhances growth performance and cellular immune response in weanling rats 总被引:1,自引:0,他引:1
Xiang‐Feng Kong Yu‐Zhe Zhang Yu‐Long Yin Guo‐Yao Wu Huai‐Jun Zhou Zhi‐Liang Tan Feng Yang Mei‐Juan Bo Rui‐Lin Huang Tie‐Jun Li Mei‐Mei Geng 《Journal of the science of food and agriculture》2009,89(12):2039-2044
BACKGROUND: In order to develop a novel dietary additive for potential application in domestic animals and humans, a fraction of Chinese yam polysaccharide (CYP) was prepared and a study was conducted to determine the effects of dietary supplementation with CYP on the immune response and growth performance in weanling rats. RESULTS: Dietary supplementation with CYP increased the average daily feed intake and average daily gain but decreased the feed/gain ratio overall compared with the non‐supplemented group. CYP also significantly increased the serum contents of interleukin‐2 and tumour necrosis factor and the proliferation activity of peripheral lymphocytes but decreased the serum contents of low‐density lipoprotein, total cholesterol and triglyceride compared with the non‐supplemented group. CONCLUSION: The increase in cellular immunity in CYP‐supplemented weanling rats confers an important protective role in the non‐specific defence against infections. This herbal polysaccharide, as a natural green dietary additive for promoting the immune response and healthy growth, may offer an effective alternative to antibiotics for weanling animals. Copyright © 2009 Society of Chemical Industry 相似文献
993.
Xiao Qin Lin Gaoyong Wang Juan Zheng Kaihong Feng Xiaowei 《Protection of Metals and Physical Chemistry of Surfaces》2021,57(1):132-138
Protection of Metals and Physical Chemistry of Surfaces - The effect of pH value on the electroless deposition of copper coated graphite powders (Cu@GPs) was investigated in this paper. The... 相似文献
994.
对A380铝合金齿轮室失效件开裂部位显微组织、化学成分等进行分析,发现在产品两侧悬置区开裂部位存在缩松、缩孔、气孔、夹渣等铸造缺陷;利用有限元数值模拟软件分析产品在恶劣工况下的应力分布情况,显示在两侧悬置区应力集中,受力较大。认为铸造缺陷和应力集中的综合影响,是导致产品开裂失效的原因。通过改进浇注排气溢流系统、调整压铸工艺参数、优化产品结构设计等手段,产品开裂比例大幅度下降。 相似文献
995.
针对容积卡尔曼滤波(cubature Kalman filter,CKF)在动力定位系统存在不良测量及船舶运动模型不确定时滤波精确度下降甚至发散的问题,提出一种强跟踪自适应CKF算法。利用新息协方差匹配原理,建立对系统的不良测量具有鲁棒性的自适应CKF。基于强跟踪滤波(strong tracking filter,STF)的理论框架和自适应CKF算法,构建强跟踪自适应CKF,该算法克服了标准强跟踪滤波的理论局限性,兼具STF与自适应CKF的优点,在系统存在模型不确定性及不良测量时具有良好的鲁棒性和滤波精确度。通过仿真验证了所建算法的有效性。 相似文献
996.
997.
998.
Mapping QTLs Controlling Beneficial Fatty Acids Based on the Embryo and Maternal Plant Genomes in Brassica napus L. 下载免费PDF全文
Juan Wen Jianfeng Xu Yan Long Haiming Xu Jianguo Wu Jinling Meng Chunhai Shi 《Journal of the American Oil Chemists' Society》2015,92(4):541-552
This study was mainly carried out to detect the quantitative trait loci (QTLs) located simultaneously in embryo and maternal plant nuclear genomes for beneficial fatty acid contents of rapeseed under different environments by using a mapping model and mapping populations from a cross of ‘Tapidor’ × ‘Ningyou7.’ Eight, three, six, seven and three QTLs respectively for palmitic, oleic, linoleic, linolenic and eicosenoic acid contents were identified and subsequently mapped on chromosomes A1, A3, A4, A6, A8, A9, C1, C3, C5, C7, C8 and C9. Among them, 12 QTLs were major ones that could respectively explain more than 10 % of phenotypic variation. Two specific genomic regions on A8 and C3 were associated with several QTLs relating to multiple fatty acid contents. Some of the markers such as HBr015 and JICB0633 showed tight linkage with the QTLs, which could be used for improving the fatty acid component(s) of rapeseed. 相似文献
999.
Nishant Singh Marta Tena-Solsona Juan F. Miravet Beatriu Escuder 《Israel journal of chemistry》2015,55(6-7):711-723
Self-assembly of small peptides offers unique opportunities for the bottom-up construction of supramolecular catalysts that aim to emulate the efficiency and selectivity of natural enzymes. Small, information-rich, simple molecules based on amino acids can self-organise autonomously into complex systems with emergent catalytic properties. The power of noncovalent interactions can be used to construct supramolecular peptidic tertiary structures. Moreover, specific functional groups present in amino acid side-chains may present either a catalytic activity by themselves or be able to bind cofactors such as metal ions. In this scenario, although relevant progress has been achieved in recent years, promising applications in biomaterials science are foreseen. In this review, we discuss the state-of-the-art of this approach at the interface between supramolecular chemistry and peptide science. 相似文献
1000.
Mario I. Chacon-Murguia Juan Ramirez-Quintana David Urias-Zavala 《Signal, Image and Video Processing》2015,9(1):135-144
We propose a novel algorithm for segmentation of video background models in time-variant scenarios. It is robust to gradual or abrupt illumination changes, diverse kind of noises, and even scenario variation. The algorithm generates regions according to the scene composition by keeping region segmentation coherence. The proposed method based on a discrete-time cellular neural network estimates the number regions in the current background model, and then, a modified k-means algorithm is used to achieve segmentation. The findings demonstrate the robustness of the method and its superiority over two state of the art scene segmentation algorithms. 相似文献