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The adhesion force between a chloride-isobutene-isoprene rubber (CIIR) and stainless steel ball was studied. To decrease the adhesion force, the CIIR rubber was treated with high-density microwave plasma employing oxygen and argon gases. The experimental results showed that the adhesion force decreases with increasing the time of oxygen and argon plasma treatments. In addition, the contact microscope measurements revealed different surface structure with two gases. The real contact area also decreased with treatment time and dramatic changes were observed after 5 min treatment of CIIR rubber. The field emission scanning electron microscope image also showed that the subsurface of CIIR rubber pattern has changed with various plasma treatments. These results imply change in the morphology of CIIR rubber surface by plasma treatment is one reason for the decrease in adhesion forces.

In order to develop a new DNA sequencing method by using chemical force microscopy (CFM), we have investigated the interaction of the hydrogen bonding between surfaces of nucleobase self-assembled monolayers (SAMs) and AFM-tips modified with the nucleobases. The two different adhesion forces, the jump-in force and pull-off force, between the AFM-tip modified with cytosine-SAM and the surfaces of four kinds of nucleobase SAMs were measured in water (20°C) by CFM. The adsorption of poly (C) onto a nucleobase-SAM on a gold electrode of quartz crystal microbalance (QCM) was measured as resonance frequency changes. The relative relation among four bases showed similar tendency in the adhesion force measured by the cytosine AFM-tip and in the adsorption amount of poly (C) on the QCM electrode as well as in the theoretically calculated interaction energies between two nucleobases.

The vibration method represents a practical method for the measurement of adhesion forces and adhesion force distributions. This method causes sinusoidally alternating stresses and yields detachment and contact forces between particles and substrate of the same order of magnitude. Alternating contact forces of the vibration method can cause an adhesion force intensification through flattening of asperities. The measuring principle of the vibration method and the analysis of experimental results are described in the article. Normal adhesion forces (pull-off forces) are measured using the vibration method and the colloidal probe technique. The results of both methods show good agreement for small particle sizes. The influence of the detachment force direction is shown by comparing tangential and normal adhesion forces measured using particle reentrainment in a turbulent air flow and the vibration method, respectively. The surface roughness of the substrate and the relative humidity are shown to significantly influence the measured adhesion forces. For the calculation of the adhesion forces, an approach by Rabinovich was combined with approximations of plastic micro asperity flattening. The Rabinovich approach accounts for roughness effects on the van der Waals force by incorporating the rms roughness of the interacting surfaces. rms-values of the particles and substrates were measured with atomic force microscopy at different scanning areas.

Experiment on the surface characteristics of polymer films (PC, PET, EVA) treated by atmospheric pressure plasma has been conducted. As the process parameters, we chose frequency, gas flow and treatment time. By measuring the contact angle, we scrutinized the effects of these parameters on the hydrophilic surface characteristics of polymer materials and found the optimum operating condition of each polymer for the highest hydropilicity. In the case of PC substrate, the contact angle was changed from 83.5 ± 1.1° (before plasma treatment) to 30.4 ± 0.4° (after plasma treatment) at the optimum operating condition of 30 kHz, CDA 0.6%, and repeated number of 7. In the case of PET substrate, the contact angle change was found from 59 ± 1.1° to 23.5 ± 1.7° at 20 kHz, CDA 0.6%, and repeated number of 7. In the case of EVA substrate, the contact angle of 84 ± 0.6° changed to 44.2 ± 1.2° at 30 kHz, CDA 0.6%, and repeated number of 7. The long-term stability of the hydrophilic surfaces and section morphology were also examined by SEM. As a roll-to-roll application, the adhesion force between PET and UV resin was measured to show initial increase according to the plasma treatment time, i.e., repeated number but finally saturated to show no meaningful change, which is in line with the behavior of the contact angle according to plasma treatment time.

In order to develop a new DNA sequencing method by using chemical force microscopy (CFM), we have investigated the interaction of the hydrogen bonding between surfaces of nucleobase self-assembled monolayers (SAMs) and AFM-tips modified with the nucleobases. The two different adhesion forces, the jump-in force and pull-off force, between the AFM-tip modified with cytosine-SAM and the surfaces of four kinds of nucleobase SAMs were measured in water (20°C) by CFM. The adsorption of poly (C) onto a nucleobase-SAM on a gold electrode of quartz crystal microbalance (QCM) was measured as resonance frequency changes. The relative relation among four bases showed similar tendency in the adhesion force measured by the cytosine AFM-tip and in the adsorption amount of poly (C) on the QCM electrode as well as in the theoretically calculated interaction energies between two nucleobases.

Hot washing has been applied with more and more frequency on power systems and splashing water has a great influence on hot washing cleaning effect, but the corresponding research was rare. Simulation analysis and theoretical research were carried out to analyze the influence of splashing water on insulator hot washing cleaning effect. The results demonstrated that splashing water will increase the cleaning range and improve the cleaning efficiency, but may also cause flashover occurrence, affecting the security of hot washing; leading to the change of cleaning mechanism. The main reason of cleaning had changed from internal water pressure to directly shear pressure. It also can improve the adhesion force as it caused high relative humidity around the contamination, but having little influence on dynamic pressure.