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981.
结合工程实例,对跨高速铁路施工防护棚架的设计和施工方案进行了研究,并对荷载、防护支架结构、防护支架拆除后钢管立柱的稳定性作了计算分析,证明了该防护棚架设计的合理性。 相似文献
982.
With the development of automobile lightweight, the requirements of steel cord for radial tire on inclusions are becoming more stringent. According to the demands of steel cord wire rod on inclusions, the smelting technology at home and abroad and the research progress on the inclusions in the steel cord at present were summarized, and some views on the control direction in future were put forward. With the 90 grade ultra high strength tire cord steel becoming the mainstream product, the Al2O3- rich type inclusion and titanium inclusion remains a difficult point of control. In addition to further strengthening the plasticity control of the inclusions in the process of smelting, the attention also should be paid on the properties and behaviors of the inclusions in each link such as rolling and drawing process, so as to better realize the whole- process control. 相似文献
983.
Stochastic adaptive estimation and control algorithms involving recursive prediction estimates have guaranteed convergence rates when the noise is not ‘too’ coloured, as when a positive-real condition on the noise mode is satisfied. Moreover, the whiter the noise environment the more robust are the algorithms. This paper shows that for linear regression signal models, the suitable introduction of while noise into the estimation algorithm can make it more robust without compromising on convergence rates. Indeed, there are guaranteed attractive convergence rates independent of the process noise colour. No positive-real condition is imposed on the noise model. 相似文献
984.
硫代葡萄糖苷(简称硫苷)是十字花科蔬菜中一类重要的次生代谢物。在蔬菜发酵过程中,硫苷被代谢为异硫氰酸盐等活性产物,这些代谢产物具有抗氧化、抗癌、调节肠道菌群等多种生理功能。乳酸菌发酵对硫苷的代谢机制包括促进硫苷从蔬菜中释放,以及使其发生降解,且代谢作用既与乳酸菌种属相关,也与发酵体系的盐含量、金属离子、pH值以及蔬菜加热预处理相关。通过总结梳理发酵蔬菜硫苷代谢研究进展,并解析影响因素,为提高发酵蔬菜中活性硫苷代谢产物含量,提升发酵蔬菜的健康效应提供理论指引。 相似文献
985.
Renal cell carcinoma (RCC) has a poor prognosis due to limited diagnosis and treatment. Thus, it is necessary to find novel prognostic biomarkers and therapeutic targets. The aberrant expression of microRNAs plays an important role in RCC oncogenesis. Tissue inhibitors of metalloproteinase 3 (TIMP3) acts as a downstream target of miR-181b. The aim of this study was to understand the role and molecular mechanism of miR-181b in RCC oncogenesis. The results showed that miR-181b expression was significantly higher in RCC tumour tissues, especially in those with significant invasion or metastasis. miR-181b overexpression promoted proliferation and migration of the RCC cell line 786-O, while miR-181b knockdown had the opposite effect. In addition, miR-181b was inversely correlated with TIMP3 expression in RCC tumour tissues. miR-181b overexpression reduced TIMP3 expression in RCC cell line 786-O or OS-RC-2, while miR-181b knockdown had the inverse effect. Mechanistically, a luciferase reporter assay confirmed the binding sites of miR-181b on the 3’-UTR of TIMP3, confirming the targeting effect of miR-181b on TIMP3. Overall, miR-181b promotes the development and progression of RCC by targeting TIMP3 expression, indicating the potential use of miR-181b in the diagnosis and treatment of RCC. 相似文献
986.
987.
LI Bin LEI Zuosheng GE Jiangmeng ZHONG Yunbo REN Zhongming ZHOU Yueming WU Cunyou 《Baosteel Technical Research》2016,(1):1-9
Through physical modeling and numerical simulation,the flow field in a slab continuous casting mold with electromagnetic stirring is measured under different casting parameters and stirring currents. To qualitatively evaluate the flow field in the mold,two indexes,i. e.,mold flux entrapment and velocity uniformity,are proposed.Based on these two indexes,some optimized stirring parameters under different casting conditions can be determined. 相似文献
988.
989.
990.
A surface soil moisture model with improved spatial resolution was developed using remotely sensed apparent thermal inertia (ATI). The model integrates the surface temperature derived from TM/ETM+ image and the mean surface temperature from MODIS images to improve the spatial resolution of soil temperature difference based on the heat conduction equation, which is necessary to calculate the ATI. Consequently, the spatial resolution of ATI and SMC can be enhanced from 1 km to 120 m (TM) or 60 m (ETM+). Moreover, the enhanced ATI has a much stronger correlation coefficient (R2) with SMC (0.789) than the surface reflectance (0.108) or the ATI derived only from MODIS images (0.264). Based on the regression statistics of the field SMC measurement and enhanced ATI, a linear regression model with an RMS error of 1.90% was found. 相似文献