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1.
潜油电泵是油田常用的一种采油设备。对潜油电泵表面进行喷漆是潜油电泵制造的最后一道工艺,能够保护潜油电泵不被锈蚀。目前国内潜油电泵喷漆都是手工喷涂,喷涂均匀性及质量难以保证,并且对操作者有很大伤害。论文叙述中研制的自动喷漆设备,能够实现自动进料和自动喷漆。现场应用表明该系统不但可实现自动喷漆,提高喷漆质量,提高喷漆效率,而且环保,减少污染,有十分明显的经济效益。 相似文献
2.
Energy hierarchy and urban landscape system 总被引:2,自引:0,他引:2
The study of ecosystems suggests principles by which the flow of energy generates hierarchies in all systems. From viewpoint of ecological energetics, urban system lies on the highest level of ecosystem hierarchy. The main objective of this paper is to study the effect of energy flows on the hierarchies and spatial organization of urban zonation. This research uses Taipei metropolitan region as the area for the case study. “Emergy” is used as the principal conceptual tool for energy analysis; “transformity” is used to measure the hierarchies of land uses and urban landscape systems. Based on the calculation of the spatial distribution of energy flows, using GIS, the empower density and transformity increase from rural to urban center. In order to delineate zones of different energetics, the 1178 administrative districts of the Taipei metropolitan region are used as units for multivariate classification, in which 19 variables of energy flows are condensed into four factors. The factor scores of each districts are then used as input for cluster analysis and discriminate analysis. As a result, different energy structures, and subsequently, different types and amount of energy flows tend to associate with different intensities of urbanization. The Taipei metropolitan region is classified into six energetic zones: mixed-use urban core; high density urban residential district; service and manufacturing urban district; agricultural district, newly developed suburban district; and natural area. The calculation of transformity and emergy indices further establish the hierarchical order of these zones. The distribution of the six energetic zones, reveals the spatial energetic hierarchies of Taipei metropolitan region. The implication of energetic characteristics to planning practice is also discussed to conclude this research. 相似文献
3.
Anodization of aluminum in acidic electrolyte containing chloride ions was used to prepare aluminum ultrafine particles (Al UFPs) for the first time. In addition, the influence of different acid electrolyte was investigated and the mechanism of generating Al UFPs is analyzed. It is found that the pitting corrosion of chloride ions plays an important role in preparing Al UFPs and the acidification of the electrolyte is in favor of the preparation. Al UFPs with different shape and size distribution were obtained via changing the type of acid. Finally, the model of generating Al UFPs via this method is proposed. 相似文献
4.
Hui-Yu Fang Uvarani Chokkalingam Shu-Fen Chiou Tsong-Long Hwang Shu-Li Chen Wei-Lung Wang Jyh-Horng Sheu 《International journal of molecular sciences》2015,16(1):736-746
A new chromene derivative, 2-(4'',8''-dimethylnona-3''E,7''-dienyl)-8-hydroxy-2,6-dimethyl-2H-chromene (1) together with four known natural products, methylfarnesylquinone (2), isololiolide (3), pheophytin a (4), and β-carotene (5) were isolated from the brown alga Homoeostrichus formosana. The structure of 1 was determined by extensive 1D and 2D spectroscopic analyses. Acetylation of 1 yielded the monoacetylated derivative 2-(4'',8''-dimethylnona-3''E,7''-dienyl)-8-acetyl-2,6-dimethyl-2H-chromene (6). Compounds 1–6 exhibited various levels of cytotoxic, antibacterial, and anti-inflammatory activities. Compound 2 was found to display potent in vitro anti-inflammatory activity by inhibiting the generation of superoxide anion (IC50 0.22 ± 0.03 μg/mL) and elastase release (IC50 0.48 ± 0.11 μg/mL) in FMLP/CB-induced human neutrophils. 相似文献
5.
目的建立一种测定牛奶及奶酪制品中低含量溶菌酶的高效液相色谱-荧光检测新方法。方法样品经p H 6.0的氯化钠溶液活化,再在低p H值条件下除蛋白后,采用反相色谱柱(PLRP-S 250 mm×4.6 mm,300?,5μm)用A水(0.1%的三氟乙酸(trifluoroacetic acid,TFA)),B乙腈(0.1%TFA)体系作为流动相进行梯度洗脱,使用荧光检测器在激发波长(λ_(ex))276 nm,发射波长(λ_(em))345 nm处检测。结果最优实验条件下,溶菌酶在2.0~30.0 mg/L浓度范围内线性良好,加标实验结果显示回收率和相对标准偏差(relative standard deviation,RSD)分别在92.3%~104.3%和0.81%~3.26%之间,对牛奶和奶酪制品的检出限分别为20和40 mg/kg。结论该方法操作简便,结果准确、可靠,可用于乳制品中溶菌酶含量测定。 相似文献
6.
7.
利用上近似、下近似等概念给出粗交流的一种新定义形式,得出该定义形式下粗交流与原定义形式下粗交流之间的关系定理。最后通过一个具体实例给出直观分析。 相似文献
8.
9.
赵淑丽 《河北水利水电技术》2012,(1):17-18
金山子水库设计洪水计算采用暴雨途径进行分析,分析时采用了推理公式法和合理化公式法复核计算,可为计算类似小水库除险加固工程设计洪水分析提供借鉴。 相似文献
10.
Multi-sensor optimal information fusion Kalman filter 总被引:3,自引:0,他引:3
This paper presents a new multi-sensor optimal information fusion criterion weighted by matrices in the linear minimum variance sense, it is equivalent to the maximum likelihood fusion criterion under the assumption of normal distribution. Based on this optimal fusion criterion, a general multi-sensor optimal information fusion decentralized Kalman filter with a two-layer fusion structure is given for discrete time linear stochastic control systems with multiple sensors and correlated noises. The first fusion layer has a netted parallel structure to determine the cross covariance between every pair of faultless sensors at each time step. The second fusion layer is the fusion center that determines the optimal fusion matrix weights and obtains the optimal fusion filter. Comparing it with the centralized filter, the result shows that the computational burden is reduced, and the precision of the fusion filter is lower than that of the centralized filter when all sensors are faultless, but the fusion filter has fault tolerance and robustness properties when some sensors are faulty. Further, the precision of the fusion filter is higher than that of each local filter. Applying it to a radar tracking system with three sensors demonstrates its effectiveness. 相似文献