scholarly journals Physical Structure Induced Hydrophobicity Analyzed from Electrospinning and Coating Polyvinyl Butyral Films

2019 ◽  
Vol 2019 ◽  
pp. 1-5 ◽  
Author(s):  
Shuo Chen ◽  
Guo-Sai Liu ◽  
Hong-Wei He ◽  
Cheng-Feng Zhou ◽  
Xu Yan ◽  
...  
Keyword(s):  
Surface Structure ◽  
Critical Role ◽  
Film Surface ◽  
Polyvinyl Butyral ◽  
Physical Structure ◽  
Surface Wettability ◽  
Practical Applications ◽  
Physical Surface ◽  
Film Forming ◽  
Surface Morphologies

Surface wettability of a film plays a critical role in its practical applications. To control the surface wettability, modification on the physical surface structures has been a useful method. In this paper, we reported the controlling physical surface structure of polyvinyl butyral (PVB) films by different film-forming methods, spin-coating, bar-coating, and electrospinning. The wettability of these PVB films was examined, and the surface morphologies and roughness were investigated. The results indicated that coating PVB films were hydrophilic, while electrospun films were hydrophobic. The physical surface structure was the key role on the interesting transition of their surface wettability. Theoretical analyses on these results found that the coating PVB films showed different mechanism with electrospun ones. These results may help to find the way to control the PVB film surface wettability and then guide for applications.

scholarly journals Application of UHF Sensors in Power System Equipment for Partial Discharge Detection: A Review

Sensors ◽  
2019 ◽  
Vol 19 (5) ◽  
pp. 1029 ◽  
Author(s):  
Hua Chai ◽  
B.T. Phung ◽  
Steve Mitchell
Keyword(s):  
Power System ◽  
Electromagnetic Interference ◽  
Early Stage ◽  
Signal To Noise Ratio ◽  
Partial Discharge ◽  
Critical Role ◽  
Physical Structure ◽  
High Signal ◽  
Practical Applications ◽  
Electrical Stress

Condition monitoring of an operating apparatus is essential for lifespan assessment and maintenance planning in a power system. Electrical insulation is a critical aspect to be monitored, since it is susceptible to failure under high electrical stress. To avoid unexpected breakdowns, the level of partial discharge (PD) activity should be continuously monitored because PD occurrence can accelerate the aging process of insulation in high voltage equipment and result in catastrophic failure if the associated defects are not treated at an early stage. For on-site PD detection, the ultra-high frequency (UHF) method was employed in the field and showed its effectiveness as a detection technique. The main advantage of the UHF method is its immunity to external electromagnetic interference with a high signal-to-noise ratio, which is necessary for on-site monitoring. Considering the detection process, sensors play a critical role in capturing signals from PD sources and transmitting them onto the measurement system. In this paper, UHF sensors applied in PD detection were comprehensively reviewed. In particular, for power transformers, the effects of the physical structure on UHF signals and practical applications of UHF sensors including PD localization techniques were discussed. The aim of this review was to present state-of-the-art UHF sensors in PD detection and facilitate future improvements in the UHF method.

Dependence of water adsorption on the surface structure of silicon wafers aged under different environmental conditions

2019 ◽  
Vol 21 (47) ◽  
pp. 26041-26048 ◽  
Author(s):  
Lei Chen ◽  
Dien Ngo ◽  
Jiawei Luo ◽  
Yunfei Gong ◽  
Chen Xiao ◽  
...  
Keyword(s):  
Surface Structure ◽  
Oxide Layer ◽  
Environmental Conditions ◽  
Water Adsorption ◽  
Physical Structure ◽  
Silicon Wafers ◽  
Surface Wettability ◽  
Physisorbed Water

The structure and isotherm thickness of physisorbed water on a Si/SiOx surface depend on surface wettability and the physical structure of the oxide layer.

scholarly journals Spreading and Drying Dynamics of Water Drop on Hot Surface of Superwicking Ti-6Al-4V Alloy Material Fabricated by Femtosecond Laser

Nanomaterials ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 899
Author(s):  
Ranran Fang ◽  
Zekai Li ◽  
Xianhang Zhang ◽  
Xiaohui Zhu ◽  
Hanlin Zhang ◽  
...  
Keyword(s):  
Femtosecond Laser ◽  
Surface Structure ◽  
Energy Savings ◽  
Water Drop ◽  
Capillary Surface ◽  
Water Flow Velocity ◽  
Capillary Action ◽  
Practical Applications ◽  
Alloy Material ◽  
Hot Surface

A superwicking Ti-6Al-4V alloy material with a hierarchical capillary surface structure was fabricated using femtosecond laser. The basic capillary surface structure is an array of micropillars/microholes. For enhancing its capillary action, the surface of the micropillars/microholes is additionally structured by regular fine microgrooves using a technique of laser-induced periodic surface structures (LIPSS), providing an extremely strong capillary action in a temperature range between 23 °C and 80 °C. Due to strong capillary action, a water drop quickly spreads in the wicking surface structure and forms a thin film over a large surface area, resulting in fast evaporation. The maximum water flow velocity after the acceleration stage is found to be 225–250 mm/s. In contrast to other metallic materials with surface capillarity produced by laser processing, the wicking performance of which quickly degrades with time, the wicking functionality of the material created here is long-lasting. Strong and long-lasting wicking properties make the created material suitable for a large variety of practical applications based on liquid-vapor phase change. Potential significant energy savings in air-conditioning and cooling data centers due to application of the material created here can contribute to mitigation of global warming.

Two-dimensional metal carbides and nitrides (MXenes): preparation, property, and applications in cancer therapy

Nanophotonics ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 2125-2145 ◽  
Author(s):  
Lu Ming Dong ◽  
Cui Ye ◽  
Lin Lin Zheng ◽  
Zhong Feng Gao ◽  
Fan Xia
Keyword(s):  
Cancer Therapy ◽  
Scientific Community ◽  
Critical Role ◽  
High Specific Surface Area ◽  
Future Perspective ◽  
Two Dimensional ◽  
Metal Carbides ◽  
Practical Applications ◽  
Two Dimensional Materials ◽  
Size And Morphology

AbstractTransition metal carbides and nitrides (MXenes), which comprise a rapidly growing family of two-dimensional materials, have attracted extensive attention of the scientific community, owing to its unique characteristics of high specific surface area, remarkable biocompatibility, and versatile applications. Exploring different methods to tune the size and morphology of MXenes plays a critical role in their practical applications. In recent years, MXenes have been demonstrated as promising nanomaterials for cancer therapy with substantial performances, which not only are helpful to clarify the mechanism between properties and morphologies but also bridge the gap between MXene nanotechnology and forward-looking applications. In this review, recent progress on the preparation and properties of MXenes are summarized. Further applications in cancer therapy are also discussed. Finally, the current opportunities and future perspective of MXenes are described.

Surface Structure and Cells Adhesion on Doped Polyethylene

2007 ◽  
Vol 567-568 ◽  
pp. 253-256
Author(s):  
Regina Mikulíková ◽  
Kateřina Kolářová ◽  
Václav Švorčík ◽  
Barbora Dvořánková ◽  
Tomáš Sopuch
Keyword(s):  
Surface Morphology ◽  
Ftir Spectroscopy ◽  
Crystalline Phase ◽  
Film Surface ◽  
Surface Wettability ◽  
Oxidized Cellulose ◽  
3T3 Fibroblasts ◽  
Doped Polymer

The properties of polyethylene doped with Ca2+ salt of oxidized cellulose was studied by different techniques. FTIR spectroscopy was used for the determination of crystalline phase in polymer film, surface wettability was determined by standard goniometry and surface morphology was examined by SEM microscopy. Adhesion of mouse 3T3 fibroblasts on the doped polymer was studied in vitro. It was found that the polyethylene doped with the cellulose derivative can be sterilized in boiling water. The number and homogeneity of adhering cells were shown to depend on the surface wettability and morphology.

Low Band-Gap Materials for Solar Cells

2021 ◽  
pp. 176-235
Keyword(s):  
Solar Cells ◽  
Band Gap ◽  
Organic Solar Cells ◽  
Charge Separation ◽  
Chemical Properties ◽  
Low Energy ◽  
Practical Applications ◽  
Film Forming ◽  
Donor And Acceptor ◽  
Induced Charge

Organic solar cells (OSCs) are discussed at length in terms of its performance leading to the generation of electricity. The key materials required for OSCs are the small organic molecules having donor and acceptor with suitable light absorption and electro-chemical properties of low energy band gap. Various structural scaffolds are highlighted with their structural design leading to film forming in an orderly manner and this morphology of film having a pivotal role in photo-induced charge separation, migration and collection at an electrode. Present day research informs that OSCs involving non fullerene based donors and acceptors are functioning with high photo conversion efficiency [PCE] of >17% and are promising candidates for practical applications.

scholarly journals Investigations on the execution and evaluation of the Pummel test for polyvinyl butyral based interlayers

2020 ◽  
Vol 5 (3) ◽  
pp. 371-396
Author(s):  
Miriam Schuster ◽  
Jens Schneider ◽  
Tuong An Nguyen
Keyword(s):  
Film Surface ◽  
Polyvinyl Butyral ◽  
Test Method ◽  
Structural Element ◽  
Binary Images ◽  
Free Film ◽  
Safety Glass ◽  
High Adhesion ◽  
Adhesion Level ◽  
Pull Tests

Abstract Laminated safety glass (LSG) is increasingly used as structural element in buildings. Of central importance for safety are the adhesion and the residual load-bearing capacity in the post fractured state. In literature a large number of tests to assess adhesion is mentioned. These include, e.g. peel tests, through-cracked-tensile/-bending tests, VW-pull tests and compressive shear tests. However, especially in industry, the Pummel test is widespread for determining the quality of adhesion in LSG with polyvinyl butyral based interlayers. This test method proves to be simple and quick to carry out: The laminate is stored at − 18 °C and then completely destroyed at room temperature with hammer blows. The adhesion level (0–10) is determined by visually comparing the adhering glass fragments with reference pictures or with the help of diagrams and tables which indicate the Pummel value as a function of the free film surface. Pummel value 0 is to be interpreted as no adhesion and Pummel value 10 as very high adhesion. Due to the lack of standardization, the execution and evaluation is very much dependent on the test institution and executive person. This paper shows different Pummel classifications that can currently be found on the market. Subsequently, approaches to the automatization and standardization of the execution and especially the evaluation of the Pummel test are shown. Three image evaluation methods in Matlab are presented, discussed and compared: (1) analysis of binary images, (2) statistical evaluation of the greyscale images and (3) texture analysis using co-occurrence matrices.

Intensity profiles along the RHEED streaks for various thin film surface morphologies

1999 ◽  
Vol 340 (1-2) ◽  
pp. 145-152 ◽  
Author(s):  
K. Mae ◽  
V.V. Moshchalkov ◽  
Y. Bruynseraede
Keyword(s):  
Thin Film ◽  
Film Surface ◽  
Thin Film Surface ◽  
Surface Morphologies

An Analysis Model and its Practical Applications in PG&E Gas Transmission Pipeline Strength Test Projects

2018 ◽  
Author(s):  
Chunlei He ◽  
Edward Stracke
Keyword(s):  
Critical Role ◽  
Ideal Gas ◽  
Strength Test ◽  
Future Application ◽  
Test Duration ◽  
Test Medium ◽  
Analysis Model ◽  
Practical Applications ◽  
Pipeline Section ◽  
Strength Tests

This article presents a complete set of calculations (referred to as Model) PG&E developed to monitor, assess and approve strength tests on insitu (pipelines currently in service) gas transmission pipelines. How the Model is used in the field, 2017 test results, and process improvements that resulted from the implementation of the model are also discussed. In compliance with CPUC directives, the Code of Federal Regulations[1] and PG&E’s internal standards, PGE has performed strength tests on approximately 1,100 miles of insitu pipelines from 2011 through 2017. The model was specifically designed to assess the strength test of a closed section of gas pipeline for both leaks and ruptures. The model was originally designed for strength tests using water as the test medium and updated to accommodate nitrogen as a test medium. A future enhancement will be to incorporate a blend of Nitrogen and Helium as the test medium. The model plots the pressure-temperature and pressure-volume curves over the test duration (field test measurements) and compares them to the theoretically calculated curves. The curves are used to determine if the change in pressure is due to temperature influence or leakage. When water is the test medium, the model calculates the net corrected medium volume change from start to end of the static test period. When nitrogen is the test medium, the model calculates and analyzes net mass change of the medium by considering nitrogen under both the real gas state and the ideal gas state. By calculating restrained (buried) pipeline section and unrestrained (exposed) pipeline section separately, the model gains more accuracy. Accurate temperature measurements play a critical role in the model. The model makes it possible for engineers to monitor, analyze and direct strength tests with real-time test data. The model is also used to evaluate the pipeline fill condition on the day prior to the actual test, which resulted in fewer test restarts due to incomplete fill or temperature stabilization issues. An additional benefit is the tests were typically completed earlier in the day. The model is utilized on all PG&E insitu pipeline strength projects today. Authors also provide improvement suggestions of this model in future application.

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