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91.
冬季黄河水强化混凝方式的优化选择 总被引:1,自引:0,他引:1
通过生产性实验,比较了活性炭与聚合硫酸铁、活性炭与聚合氯化铝铁、活性炭与聚合硫酸铁和聚合氯化铝铁三种强化混凝方式的混凝效果。结果证明,对于冬季黄河水的处理,利用活性炭与聚合硫酸铁和聚合氯化铝铁的强化混凝方式效果最优。 相似文献
92.
进行了交联聚合物溶液在多孔介质中的流动试验,观察到交联聚合物溶液的蠕变回复现象,说明交联聚合物溶液在多孔介质中产生了粘弹效应.通过交联聚合物溶液变流速(67,161,67 cm/d)与恒速(67 cm/d)驱油时,即存在蠕变回复效应和无蠕变回复效应驱油,考察交联聚合物溶液蠕变回复效应对驱油效率的影响,结果表明,在本实验条件下,蠕变回复效应能增加原油采收率1.5%. 相似文献
93.
利用昆虫病毒防治害虫是生物防治的一种有效方法。主要针对昆虫病毒的作用机制、后效作用以及重组昆虫病毒和昆虫病毒感染增效物质等方面进行了阐述。 相似文献
94.
针对当前以人工智能为基础的墙体裂缝识别主要以图像识别为主,容易受到裂痕特征分布不均匀的影响,识别精度不高的问题,提出基于特征分布和高斯混合模型的建筑墙体裂缝图像识别方法.采用Harris角点检测算法对墙体图像进行角点求解处理,对建筑墙体图像进行预处理;通过选择掩模平滑法对墙体图像进行增强处理,将特征分布和高斯混合模型相结合,实现对建筑墙体裂缝图像的高精度识别.结果表明,该方法识别精度较高且识别时间短,预处理效果明显增强. 相似文献
95.
Luminescent liquid crystals (LLCs) have attracted significant interest for organic optoelectronic applications, especially for the generation of linear polarized light. Here, a novel LLC molecule, 2-(4-(nonanealkoxy)phenyl)-3-(4-formamidephenyl)-acrylonitrile (CN-NPFA), is reported, which shows strong fluorescence in the solid state due to the aggregation-induced enhanced emission (AIEE) effect. Moreover, a well-aligned liquid crystalline film using AIEE-active molecules, is obtained using an in-plane electric field with an alignment layer. It exhibits highly polarized luminescence (ρ = 0.74) with a high fluorescence quantum yield. The device is both cheap and easy to fabricate, and has the potential to be used in practical electro-optic applications. 相似文献
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Amanda Alonso Xavier Muñoz‐Berbel Núria Vigués Rosalía Rodríguez‐Rodríguez Jorge Macanás Maria Muñoz Jordi Mas Dmitri N. Muraviev 《Advanced functional materials》2013,23(19):2450-2458
Cation exchange polymeric matrices are widely used in water treatment protocols to reduce the mineral content of hard waters, even for human consumption. However, they are not antibacterial and flowing bacteria can be trapped in their structures and proliferate, thus acting as microbial contamination sources. Here, Ag@Co‐nanoparticles (Ag@Co‐NPs) with a low‐cost superparamagnetic Co0‐core and an antibacterial Ag‐shell are synthesized on granulated cation exchange polymeric matrices under soft reaction conditions. The presence of these NPs provides the final nanocomposite (NC) with additional functionalities (superparamagnetism and antibacterial activity) making it ideal for water purification applications. Ag@Co‐NPs are synthesized in situ on four cation exchange polymeric matrices containing either strong (sulfonic) or weak (carboxylic) acid functional groups homogeneously distributed (C‐type) or concentrated on an external shell (SST‐type) by the intermatrix synthesis (IMS) method. The NCs are characterized (metal content, NP size and distribution, metal oxidative state, and metal release) and evaluated for water purification applications. 相似文献
100.
This paper proposes a novel hybrid technique called enhanced grey wolf optimization-sine cosine algorithm-cuckoo search (EGWO-SCA-CS) algorithm to improve the electrical power system stability. The proposed method comprises of a popular grey wolf optimization (GWO) in an enhanced and hybrid form. It embraces the well-balanced exploration and exploitation using the cuckoo search (CS) algorithm and enhanced search capability through the sine cosine algorithm (SCA) to elude the stuck to the local optima. The proposed technique is validated with the 23 benchmark functions and compared with state-of-the-art methods. The benchmark functions consist of unimodal, multimodal function from which the best suitability of the proposed technique can be identified. The robustness analysis also presented with the proposed method through boxplot, and a detailed statistical analysis is performed for a set of 30 individual runs. From the inferences gathered from the benchmark functions, the proposed technique is applied to the stability problem of a power system, which is heavily stressed with the nonlinear variation of the load and thereby operating conditions. The dynamics of power system components have been considered for the mathematical model of a multimachine system, and multiobjective function has been framed in tuning the optimal controller parameters. The effectiveness of the proposed algorithm has been assessed by considering two case studies, namely, (i) the optimal controller parameter tuning, and (ii) the coordination of oscillation damping devices in the power system stability enhancement. In the first case study, the power system stabilizer (PSS) is considered as a controller, and a self-clearing three-phase fault is considered as the system uncertainty. In contrast, static synchronous compensator (STATCOM) and PSS are considered as controllers to be coordinated, and perturbation in the system states as uncertainty in the second case study. 相似文献