Dynamic Wettability of Rice Straw

With JC2000A Contact Angle Measuring Apparatus and established model of rice straw surface wetting, to improve the surface wetting properties of Rice Straw, effects of four kinds of alkali spray on Rice Straw at room temperature on contact angle was studied. The result shows that after alkali treatment the surface wettability of Rice Straw obtained significant improvement, contact angle decreases with the treatment time extended. The contact angle change rate reached the largest within 10min with the decreasing gradient of 20.64% when rice straw was dealt with NaNH2 at the mass fraction of 1%. Under the same conditions, rice straw processing with CaH2 has the minimum gradient contact angle change rate of 3.6%, A large number of Ca(OH)2 formation made The contact angle did not change significantly with time extended. Effect of NaOH treatment changed significantly over time, the optimum conditions of processing technology were obtained through orthogonal test: concentration of NaOH is 0.6%,solvent ratio 1:3.5 and reaction time 12h.

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Effects of Different Treatments on Surface Activity of Rice Straw Particleboard

Science of Advanced Materials ◽

10.1166/sam.2020.3528 ◽

2020 ◽

Vol 12 (2) ◽

pp. 289-295 ◽

Cited By ~ 4

Author(s):

Xian-Qing Xiong ◽

Ying-Ying Yuan ◽

Yi-Ting Niu ◽

Liang-Ting Zhang ◽

Zhi-Hui Wu

Keyword(s):

Rice Straw ◽

Surface Activity ◽

Treatment Time ◽

Ph Value ◽

Sodium Hydroxide Solution ◽

Alkali Treatment ◽

Surface Absorption ◽

Bonding Performance ◽

Absorption Performance ◽

Corona Treatment

The surface activity of rice straw particleboard (RSP), which has a significant effect on the finishing and bonding performance, is reduced by wax coating and free radicals on the straw fiber. The RSP surface was treated by corona treatment and alkali treatment to reveal the effects of different treatments on the surface activity of RSP. The infiltration height method was applied to evaluate the variation of surface activity. The alkalized samples of RSP with different densities were prepared by using sodium hydroxide solution with pH value of 8∼14. The samples of different densities were then subjected to corona treatment under high purity oxygen conditions with treatment power of 50 W, 100 W, 300 W, and 500 W and with a time of 4 min or 7 min. The surface activity of the treated specimens was evaluated by measuring the absorption properties of three kinds of liquids by infiltration-height method: distilled water, glycerin, and alcohol. The results revealed the following. (1) After alkalization treatment, the surface absorption performance of RSP for these three liquids was improved, and it increased with the increase of pH value of the treatment solution. The suitable pH value of the alkalized solution for RSP is 7∼11, which can improve the surface absorption performance. (2) After corona treatment, the surface absorption performance of RSP increased with the increase of corona treatment power. RSP had the highest surface absorption performance for alcohol. With the density of RSP increased, the surface absorbability slightly decreased. Therefore, it is not suitable to utilize corona treatment in improving absorption for the higher density RSP. At the same time, with the variation of corona treatment time, the absorption of RSP surface changed irregularly because of the polarity of different test liquids. (3) The reasonable parameters of alkalization treatment and corona treatment are beneficial in improving the gluability of RSP. These results have guiding significance for RSP surface decoration process.

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Effects of Stoichiometry on Structural, Morphological and Nanomechanical Properties of Bi2Se3 Thin Films Deposited on InP(111) Substrates by Pulsed Laser Deposition

Coatings ◽

10.3390/coatings10100958 ◽

2020 ◽

Vol 10 (10) ◽

pp. 958

Author(s):

Yeong-Maw Hwang ◽

Cheng-Tang Pan ◽

Bo-Syun Chen ◽

Phuoc Huu Le ◽

Ngo Ngoc Uyen ◽

...

Keyword(s):

Thin Films ◽

Contact Angle ◽

Pulsed Laser Deposition ◽

Pulsed Laser ◽

Laser Deposition ◽

Surface Wetting ◽

Average Roughness ◽

X Ray ◽

Force Microscopy ◽

Wetting Properties

In the present study, the structural, morphological, compositional, nanomechanical, and surface wetting properties of Bi2Se3 thin films prepared using a stoichiometric Bi2Se3 target and a Se-rich Bi2Se5 target are investigated. The Bi2Se3 films were grown on InP(111) substrates by using pulsed laser deposition. X-ray diffraction results revealed that all the as-grown thin films exhibited were highly c-axis-oriented Bi2Se3 phase with slight shift in diffraction angles, presumably due to slight stoichiometry changes. The energy dispersive X-ray spectroscopy analyses indicated that the Se-rich target gives rise to a nearly stoichiometric Bi2Se3 films, while the stoichiometric target only resulted in Se-deficient and Bi-rich films. Atomic force microscopy images showed that the films’ surfaces mainly consist of triangular pyramids with step-and-terrace structures with average roughness, Ra, being ~2.41 nm and ~1.65 nm for films grown with Bi2Se3 and Bi2Se5 targets, respectively. The hardness (Young’s modulus) of the Bi2Se3 thin films grown from the Bi2Se3 and Bi2Se5 targets were 5.4 GPa (110.2 GPa) and 10.3 GPa (186.5 GPa), respectively. The contact angle measurements of water droplets gave the results that the contact angle (surface energy) of the Bi2Se3 films obtained from the Bi2Se3 and Bi2Se5 targets were 80° (21.4 mJ/m2) and 110° (11.9 mJ/m2), respectively.

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On Studying Surface and Nanomechanical Properties of Ti-O Films by Alkali Treatment

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.138-139.821 ◽

2011 ◽

Vol 138-139 ◽

pp. 821-825 ◽

Cited By ~ 1

Author(s):

Feng Wen ◽

Yang Cao ◽

Yu Zhou

Keyword(s):

Contact Angle ◽

Treatment Time ◽

Alkali Treatment ◽

Chemical Properties ◽

Nanomechanical Properties ◽

Angle Measurements ◽

Contact Angle Measurements ◽

Micro Arc Oxidation ◽

The Times ◽

And Chemical Properties

Titanium oxide (Ti-O) films have been widely used in the fields of electron, photology and medicine due to its distinctive optical, electrical and chemical properties. In this paper, Ti-O films were synthesized by micro-arc oxidation firstly, and then surface was modified by NaOH alkali solution under different treatment time. The wettabilities of as-prepared films were investigated by contact angle measurements using four common liquids. nanoindentation was adopted to obtain the films’ nanohardness and modulus. The results show that Ti-O films tend towards hydrophilia and its surface energy increased after alkali treatment, but no obvious effects to nanohardness and modulus of Ti-O films. Surface roughness of Ti-O films increases after alkali treatment firstly, but decreased with continuing to increasing the times of alkali treatment.

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Contact Angles as a Measure of Surface Wetting Properties in Filth Flotation Analysis

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/47.3.520 ◽

1964 ◽

Vol 47 (3) ◽

pp. 520-529

Author(s):

Maryvee G Yakowitz ◽

William V Eisenberg

Keyword(s):

Contact Angle ◽

Aqueous Phase ◽

Aqueous Media ◽

Contact Angles ◽

Surface Wetting ◽

Inverted Position ◽

Oil Droplet ◽

Wetting Properties ◽

Specimen Material ◽

Aqueous Solvent

Abstract A study was made of the surface wetting properties exhibited by insect fragments, animal hairs, and food particles in contact with oil and aqueous solvent systems used in oil flotation analytical procedures. The differential wetting phenomena involved in flotation separation procedures of both untreated and preliminarily treated materials can be studied by contact angle measurements, which provide valuable information about the degree of wettability and flotability of both filth and plant particles. The solid specimen material is immersed in an inverted position in the aqueous plase, and the applied oil droplet competes with the aqueous phase for "wetting" the solid. The contact angle is measured at the point where the oil droplet, the aqueous phase, and the solid surface meet. The instrument used for measuring contact angles and the accessory apparatus devised for the addition of oil droplets to inverted specimen mounts while immersed in aqueous media are illustrated.

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Capacitance Effects of a Hydrophobic-Coated Ion Gel Dielectric on AC Electrowetting

Micromachines ◽

10.3390/mi12030320 ◽

2021 ◽

Vol 12 (3) ◽

pp. 320

Author(s):

Taewoo Lee ◽

Sung-Yong Park

Keyword(s):

Contact Angle ◽

Experimental Studies ◽

Frequency Region ◽

Mixing Enhancement ◽

High Capacitance ◽

Angle Change ◽

Gel Layer ◽

Resonance Frequencies ◽

Ion Gel ◽

Capacitance Effects

We present experimental studies of alternating current (AC) electrowetting dominantly influenced by several unique characteristics of an ion gel dielectric in its capacitance. At a high-frequency region above 1 kHz, the droplet undergoes the contact angle modification. Due to its high-capacitance characteristic, the ion gel allows the contact angle change as large as Δθ = 26.4°, more than 2-fold improvement, compared to conventional dielectrics when f = 1 kHz. At the frequency range from 1 to 15 kHz, the capacitive response of the gel layer dominates and results in a nominal variation in the angle change as θ ≈ 90.9°. Above 15 kHz, such a capacitive response of the gel layer sharply decreases and leads to the drastic increase in the contact angle. At a low-frequency region below a few hundred Hz, the droplet’s oscillation relying on the AC frequency applied was mainly observed and oscillation performance was maximized at corresponding resonance frequencies. With the high-capacitance feature, the ion gel significantly enlarges the oscillation performance by 73.8% at the 1st resonance mode. The study herein on the ion gel dielectric will help for various AC electrowetting applications with the benefits of mixing enhancement, large contact angle modification, and frequency-independent control.

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Preparation and the Blood Compatibility of Titanium Oxide Nanorod Arrays

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.306-307.25 ◽

2011 ◽

Vol 306-307 ◽

pp. 25-30 ◽

Cited By ~ 2

Author(s):

Ping Luo ◽

Zhan Yun Huang ◽

Di Hu Chen

Keyword(s):

Contact Angle ◽

Surface Morphology ◽

Titanium Oxide ◽

Tin Oxide ◽

Growth Parameters ◽

Blood Compatibility ◽

Contact Angle Measurement ◽

Angle Measurement ◽

Nanorod Arrays ◽

Wetting Properties

In this work, titanium oxide nanorod arrays were fabricated by using the hydrothermal method on fluorine-doped tin oxide (FTO) coated glass. The diameter of the nanorods could be controlled from 150 nm to 30 nm by changing the growth parameters. The surface morphology and the structure of the samples were characterized by SEM and XRD. The wetting properties were identified by contact angle measurement. Platelet attachment was investigated to evaluate the blood compatibility of the samples with different nanoscale topographies. Results show that the nanotopographical surfaces perform outstanding blood compatibility, and the adhering platelet decreased with the increasing diameter of the nanorods.

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The Modification of Carbon Included Polyethylene Surface by Plasma Treatment for Metallizing Using a Low Pressure RF Discharge Plasma

Journal of Advanced Oxidation Technologies ◽

10.1515/jaots-2005-0111 ◽

2005 ◽

Vol 8 (1) ◽

Author(s):

Jeou-Long Lee ◽

Chung-Ming Liu ◽

Kuen Ting ◽

Wei-Kung Cheng ◽

Takayoshi Tsuchida ◽

...

Keyword(s):

Surface Roughness ◽

Contact Angle ◽

Surface Layer ◽

Discharge Plasma ◽

Treatment Time ◽

Low Pressure ◽

Rf Discharge ◽

Nickel Layer ◽

Good Adhesion ◽

Polyethylene Surface

AbstractSurface modification of the carbon included polyethylene (semi-conductive PE) surface for metallizing using a low pressure RF discharge plasma has been carried out. The contact angle was used as a measure of the wettability of the PE surface. The roughness and the chemical bondings in PE surface layer were analized by DFM and XPS, respectively. Typical results show that the contact angle decreases from approximately 94° to below 10° after several minutes' treatment and recovers to a saturation value when it was put open to the air after treatment. The saturation value of the contact angle is smaller as the gas pressure for treatment is higher and the treatment time is longer but all are below approximately 60° which is still smaller than that of untreated. DFM and XPS results show that the surface roughness and the bondings C-O and C=O in the PE surface layer also increase with increasing the treatment time and seem to be responsible for improving the hydrophilic property of PE. After pretreatment process, nickel was coated on the PE sheet by electrodeposition method and a good adhesion between the nickel layer and the PE surface compared with that of untreated was obtained.

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Study on the Rice Straw Pretreated with NaOH for Biogasification

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.197-198.140 ◽

2011 ◽

Vol 197-198 ◽

pp. 140-146

Author(s):

Jia You Li ◽

Xiao Mei Ye ◽

Jian Xing Yu ◽

Li Ling Cai ◽

Shan Ming Ruan ◽

...

Keyword(s):

Response Surface ◽

Rice Straw ◽

Surface Analysis ◽

Treatment Time ◽

Polynomial Equation ◽

Ftir Analysis ◽

Sem Images ◽

Box Behnken Design ◽

Naoh Pretreatment ◽

Main Factors

In this study, Box-Behnken design (BBD) and response surface analysis (RSA) methodology were employed to plan experiments and optimize the NaOH pretreatment of rice straw. Experimental results showed that concentration of NaOH (CS), treatment time (TT) and ratio of rice straw with NaOH (RS) were main factors governing the biogasification of rice straw. The polynomial equation describing the biogasification as a simultaneous function of the CS, TT and RS was confirmed. The FTIR analysis and SEM images of straws further confirmed that NaOH could disrupt the silicified waxy surface, break down the lignin-hemicellulose complex and partially remove silicon and lignin from the pretreated rice straw.

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Capillary transfer of soft films

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2000340117 ◽

2020 ◽

Vol 117 (10) ◽

pp. 5210-5216 ◽

Cited By ~ 4

Author(s):

Yue Zhang ◽

Mengtian Yin ◽

Yongmin Baek ◽

Kyusang Lee ◽

Giovanni Zangari ◽

...

Keyword(s):

High Speed ◽

Computational Analysis ◽

Liquid Surface ◽

Theoretical Models ◽

Dynamic Contact ◽

Surface Wetting ◽

Motion Direction ◽

Wetting Properties ◽

Geometric Patterns ◽

Solid Substrates

Existing transfer technologies in the construction of film-based electronics and devices are deeply established in the framework of native solid substrates. Here, we report a capillary approach that enables a fast, robust, and reliable transfer of soft films from liquid in a defect-free manner. This capillary transfer is underpinned by the transfer front of dynamic contact among receiver substrate, liquid, and film, and can be well controlled by a selectable motion direction of receiver substrates at a high speed. We demonstrate in extensive experiments, together with theoretical models and computational analysis, the robust capabilities of the capillary transfer using a versatile set of soft films with a broad material diversity of both film and liquid, surface-wetting properties, and complex geometric patterns of soft films onto various solid substrates in a deterministic manner.

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