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81.
82.
Ni–Co alloys have a wide range of applications in various fields owning to their excellent physical, chemical, and mechanical properties. In this paper, we prepare Ni–Co alloy coatings on 316L stain steel surfaces by electroplating. We present a novel approach utilizing a nanosecond laser to induce microtextures on Ni–Co alloy coatings. We study experimentally the effects of laser power and scanning rate on the surface morphologies of Ni–Co alloy coatings. The results indicate that the shape and size of induced microtextures can be controlled by the laser power and scanning rate. The size of grains increases with increase in the work current of the laser (WCL) at a certain scanning rate. With the WCL constant, the size of grains decreases with increase in scanning rate while their average height increases. It is a simple and easily-controlled method for the fabrication of microstructures on Ni–Co alloy coatings, which has promising applications in investigations of the properties of microtextured surfaces, such as friction, adhesion, and wetting.  相似文献   
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84.
陆昕  周雄  钱帅伟  潘笑 《应用声学》2020,39(4):638-646
随着电力需求的逐年增长,干式变压器的数量也在不断增加。干式变压器在运行时存在着振动和噪声的问题,为了对干式变压器振动的规律与特点进行研究,本文建立了干式变压器本体振动的有限元仿真模型,通过电磁分析获得相应的磁场分布,然后利用结构动力学分析得到其本体振动的相关规律。通过对处于运行状态的变压器振动数据进行实测分析,得到变压器振动的特征频率,然后对仿真结果进行对比分析,可以发现振动幅度与频率之间存在的关系。本文的研究结果可对干式变压器的减振降噪研究提供参考。  相似文献   
85.
Zhou  Ping  Ma  Jun  Tang  Jun 《Nonlinear dynamics》2020,100(3):2353-2364
Nonlinear Dynamics - Dynamics in fractional order systems has been discussed extensively for presenting a possible guidance in the field of applied mathematics and interdisciplinary science. Within...  相似文献   
86.
CdS sensitized NiO electrode was used as the photoactive cathode in a photoelectrochemical cell for water splitting,avoiding the use of a sacrificial electron donor.Photocurrent increment under visible light irradiation was observed after integration of[Co(dmgH)2(4-Me-py)Cl](1) to the photocathode,suggesting 1 could accept electrons from photoexcited CdS for water reduction and NiO could move the holes in the valence band of CdS to anode for water oxidation.  相似文献   
87.
A new approach has been developed to improve SO2 sorption by cyano‐containing ionic liquids (ILs) through tuning the basicity of ILs and cyano–sulfur interaction. Several kinds of cyano‐containing ILs with different basicity were designed, prepared, and used for SO2 capture. The interaction between these cyano‐containing ILs and SO2 was investigated by FTIR and NMR methods. Spectroscopic investigations and quantum chemical calculations showed that dramatic effects on SO2 capacity originate from the basicity of the ILs and enhanced cyano–sulfur interaction. Furthermore, the captured SO2 was easy to release by heating or bubbling N2 through the ILs. This efficient and reversible process, achieved by tuning the basicity of ILs, is an excellent alternative to current technologies for SO2 capture.  相似文献   
88.
In addition to generation of a methyl radical, formation of a formaldehyde molecule was observed in the thermal reaction of methane with AuNbO3+ heteronuclear oxide cluster cations. The clusters were prepared by laser ablation and mass‐selected to react with CH4 in an ion‐trap reactor under thermal collision conditions. The reaction was studied by mass spectrometry and DFT calculations. The latter indicated that the gold atom promotes formaldehyde formation through transformation of an Au?O bond into an Au?Nb bond during the reaction.  相似文献   
89.
Mansour  Fotouh R.  Zhou  Ling  Danielson  Neil D. 《Chromatographia》2015,78(23):1427-1442

The wide range of applications of poly(ethylene)glycol (PEG) in primarily chromatography and other closely related analytical methods has been reviewed. PEG has been used as mobile phase modifier in capillary electrophoresis (CE) as well as ion exchange, size exclusion, and hydrophobic interaction liquid chromatography (LC) methods. Generally in the presence of PEG, LC retention of macromolecules is altered and stability of their structure is maintained. PEG was effective in CE as a permanent coating for fused silica capillaries to shield free silanol groups that can cause protein adsorption to the wall resulting in band broadening and low recovery of the separated proteins. In gas chromatography, PEG-based stationary phases were applied for separation of polar analytes. PEG could also serve as an extraction medium in solid phase microextraction and aqueous two phase systems. Selected analytical applications, primarily LC and CE, involving PEG to facilitate the determination of either small molecules or macromolecules such as proteins in their native form are discussed and representative figures provided.

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90.
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