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141.
桥梁健康监测中损伤特征提取的小波包方法 总被引:2,自引:0,他引:2
针对桥梁健康监测中结构损伤识别的特点,从模式识别的角度提出和分析了损伤特征提取问题.阐述了基于小波包分析的两种节点能量特征提取的方法.为了研究小波包系数节点能量和小波包信号成分节点能量对损伤信息进行特征提取的差异,通过对随机荷载激励下的连续梁进行数值模拟,得到了结构未损和损伤状态下的加速度时程信号.应用小波包变换,对不同结构状态下的加速度信号分别提取了两种小波包节点能量特征,并对它们作为结构损伤特征指标的敏感性进行了比较.认为两种特征指标的敏感性相差很小,而小波包系数节点能量特征指标的计算效率更高,更适合桥梁健康监测中损伤特征提取的要求. 相似文献
142.
Wenlu Song Rui Huang Hao Guo Chunguang Yin Chuanling Wang Jun Cheng Weijuan Yang 《中国化学工程学报》2021,37(9):114-120
Steam pretreatment was employed to disrupt microalgal cells for lipids extraction.Effects of steam pre-treatment on microstructure of microalgal cells were investigated through scanning electron microscopy(SEM) and transmission electron microscopy (TEM).Effect of treatment on lipid extraction was also stud-ied.Microalgal cell walls were distorted after steam pretreatment due to the hydrolysis of organic macro-molecules contained in cell wall.Maximum curvature was increased from 1.88 × 10-6 m-1 to 1.43 × 10-7 m-1 after treatment with the steam at 130 ℃.The fractal dimension of microalgal cells increased from 1.25 to 1.30 after pretreatment for 15 min,and further increased to 1.47 when the pre-treatment time was increased to 60 min.Increased steam pretreatment temperature and time enhanced the hydrolysis of organic macromolecules,and finally destroyed microalgal cell walls at pretreatment temperature of 130 ℃ and pretreatment time of 60 min.Lipid extracted from wet microalgal was signif-icantly increased (2.1-fold) after pretreatment. 相似文献
143.
Maria Buuales Maria Cristina Ballesteros-Briones Manuela Gonzalez-Aparicio Sandra Hervas-Stubbs Eva Martisova Uxua Mancheo Ana Ricobaraza Sara Lumbreras Cristian Smerdou Ruben Hernandez-Alcoceba 《International journal of molecular sciences》2021,22(8)
Immune checkpoint inhibitors (ICIs) have demonstrated remarkable efficacy in a growing number of malignancies. However, overcoming primary or secondary resistances is difficult due to pharmacokinetics issues and side effects associated with high systemic exposure. Local or regional expression of monoclonal antibodies (mAbs) using gene therapy vectors can alleviate this problem. In this work, we describe a high-capacity adenoviral vector (HCA-EFZP-aPDL1) equipped with a mifepristone-inducible system for the controlled expression of an anti-programmed death ligand 1 (PD-L1) blocking antibody. The vector was tested in an immune-competent mouse model of colorectal cancer based on implantation of MC38 cells. A single local administration of HCA-EFZP-aPDL1 in subcutaneous lesions led to a significant reduction in tumor growth with minimal release of the antibody in the circulation. When the vector was tested in a more stringent setting (rapidly progressing peritoneal carcinomatosis), the antitumor effect was marginal even in combination with other immune-stimulatory agents such as polyinosinic-polycytidylic acid (pI:C), blocking mAbs for T cell immunoglobulin, mucin-domain containing-3 (TIM-3) or agonistic mAbs for 4-1BB (CD137). In contrast, macrophage depletion by clodronate liposomes enhanced the efficacy of HCA-EFZP-aPDL1. These results highlight the importance of addressing macrophage-associated immunoregulatory mechanisms to overcome resistance to ICIs in the context of colorectal cancer. 相似文献
144.
Emad Karrar Isam A. Mohamed Ahmed Muhammad Faisal Manzoor Frederick Sarpong Wei Wei Xingguo Wang 《European Journal of Lipid Science and Technology》2021,123(3):2000104
Cucurbitaceae family seeds are mostly discarded as agro-industrial wastes. Gurum (Citrullus lanatus var. colocynthoide) is an underutilized wild cucurbit plant, closely related to desert watermelon, which is grown abundantly in some African countries. Gurum seeds can play a significant role in health and nutrition due to their high oil content. This review describes the nutritional composition of gurum seeds and their oil profile. Gurum seeds are a good source of oil (27–35.5%), fiber (26–31%), crude protein (15–18%), and carbohydrates (14–17%). Gurum seeds oil is extracted by supercritical CO2 (SFE), screw press, and solvent extraction techniques. The gurum seeds oil is composed of unsaturated fatty acids with a high proportion of linoleic acid (C18:2) and oleic acid (C18:1). Gurum seeds oil contains various bioactive compounds, such as tocopherols, phytosterols, and polyphenols. It is reported that solvent extraction gives a higher yield than the screw press and SFE, but the SFE is preferred due to safety issues. More studies are required for producing better quality gurum seeds oil by using novel extraction techniques that can increase oil yield. 相似文献
145.
以空间向量几何理论为基础,详细地分析了Gauss-Markov线性模型的几何性质;在实现了模型图形化描述的基础上,利用各解向量的几何及统计性质构造出了不同情形下的统计检验方法和相应的检验统计量,为全面、深入地研究和灵活运用该模型提出了一种简洁直观的数学方法 相似文献
146.
Two new types of extraction replicas for precipitate analysis in steels have been developed. These replicas, based on alumina, allow accurate quantification of the carbon to nitrogen ratios in carbo-nitride precipitates using parallel electron energy loss spectroscopy in the TEM. Experiments on microalloyed steels show the importance of the nitrogen content in promoting precipitation even at low temperatures. 相似文献
147.
亚砜萃取Pd(Ⅱ)的结构及性能研究 总被引:5,自引:2,他引:5
系统研究了不同结构的二烷基(芳基)亚砜对Pd(Ⅱ)的萃取性能,以及亚砜的结构对萃取性能的影响,还研究亚砜-Pd(Ⅱ)配合物的结构. 相似文献
148.
萃取预分离法分离富铕中钇矿新工艺 总被引:2,自引:0,他引:2
采用一种新的串级萃取方式--萃取预分离法分离富铕中钇矿的新工艺.原料首先流入十几的三出口预先粗分离工艺,其萃余液La~Gd(TbDy)直接流入Nd/Sm工艺;中间出口流入(Gd)Tb~HoY(Er)Gd~Dy/Ho~LuY细分离工艺;出口负载有机相(Ho)Er~LuY流入Gd~Dy/Ho~LuY的洗涤段.结果表明,新工艺的粗分离工艺将占原料约70%的La~Gd(TbDy)预分离掉,使流入Gd~Dy/Ho~LuY工艺的稀土量减少约70%;由于Gd~Dy/Ho~LuY分组的萃余液GdTbDy含Ho2O3小于0.03%,省去原工艺的GdTbDy/HoY分离;新工艺的处理能力提高30%,酸碱消耗减少20%以上,贵重稀土元素Eu和Tb的存槽量大大减少. 相似文献
149.
150.