Kinds Of Liquids Research Articles

Rapid fabrication of superamphiphobic surface on AZ91D Mg alloys with re-entrant structures

Developing spray/template-free superamphiphobic surfaces that can resist various kinds of liquids is crucial for academic study and practical demands. In spite of significant evolution, facilely fabricating superamphiphobic surfaces remains a daunting challenge due to the practical dilemma of the time-consuming preparation process and the guarantee of wettability performance. Herein, a facile magnetron-sputtering-assisted chemical deposition technique is advanced to constitute hierarchical dendritic fractal structures on AZ91D Mg alloys that showcase remarkable biomimicry while significantly contributing to superamphiphobicity through extended re-entrant structures. As well as demonstrating promising chemical stability, such surfaces can display exceptional resistance to water and ethylene glycol. The approach employed to create such instrumental superamphiphobic surfaces offers substantial benefits in affordability and efficiency. Remarkably, the entire preparation process only takes 26 min, presenting a novel method for preparing superamphiphobic surfaces.

Determination of liquid viscosity based on dual-frequency-band particle tracking

Abstract An optical-tweezers-based dual-frequency-band particle tracking system was designed and fabricated for liquid viscosity detection. On the basis of the liquid viscosity dependent model of the particle’s restricted Brownian motion with the Faxén correction taken into account, the liquid viscosity and optical trap stiffness were determined by fitting the theoretical prediction with the measured power spectral densities of the particle’s displacement and velocity that were derived from the dual-frequency-band particle tracking data. When the SiO2 beads were employed as probe particles in the measurements of different kinds of liquids, the measurement results exhibited a good agreement with the reported results, as well as a detection uncertainty better than 4.6%. This kind of noninvasive economical technique can be applied in diverse environments for both in situ and ex situ viscosity detection of liquids.

Systematic Investigation of the Degradation Properties of Nitrile-Butadiene Rubber/Polyamide Elastomer/Single-Walled Carbon Nanotube Composites in Thermo-Oxidative and Hot Oil Environments.

The physical blending method was used in order to prepare nitrile-butadiene rubber/polyamide elastomer/single-walled carbon nanotube (NBR/PAE/SWCNT) composites with better thermal-oxidative aging resistance. The interactions between SWCNTs and NBR/PAE were characterized using the Moving Die Rheometer 2000 (MDR 2000), rheological behavior tests, the equilibrium swelling method, and mechanical property tests. The 100% constant tensile stress and hardness of NBR/PAE/SWCNT composites increased from 2.59 MPa to 4.14 MPa and from 62 Shore A to 69 Shore A, respectively, and the elongation decreased from 421% to 355% with increasing SWCNT content. NBR/PAE/SWCNT composites had improved thermal-oxidative aging resistance due to better interactions between SWCNTs and NBR/PAE. During the aging process, the tensile strength and elongation at break decreased with the increase in aging time compared to the unaged samples, and the constant tensile stress gradually increased. There was a more significant difference in the degradation of mechanical properties when aged in a variety of oils. The 100% constant tensile stress of NBR/PAE/SWCNT composites aged in IRM 903 gradually increased with aging time while it gradually decreased in biodiesel. The swelling index gradually increased with increasing SWCNT content. Interestingly, the swelling index of the composites in cyclohexanone decreased with the increase in SWCNT content. The reasons leading to different swelling behaviors when immersed in different kinds of liquids were investigated using the Hansen solubility parameter (HSP) method, which provides an excellent guide for the application of some oil-resistant products.

Guided Acoustic Waves in Polymer Rods with Varying Immersion Depth in Liquid.

Monitoring tanks and vessels play an important part in public infrastructure and several industrial processes. The goal of this work is to propose a new kind of guided acoustic wave sensor for measuring immersion depth. Common sensor types such as pressure sensors and airborne ultrasonic sensors are often limited to non-corrosive media, and can fail to distinguish between the media they reflect on or are submerged in. Motivated by this limitation, we developed a guided acoustic wave sensor made from polyethylene using piezoceramics. In contrast to existing sensors, low-frequency Hanning-windowed sine bursts were used to excite the L(0,1) mode within a solid polyethylene rod. The acoustic velocity within these rods changes with the immersion depth in the surrounding fluid. Thus, it is possible to detect changes in the surrounding media by measuring the time shifts of zero crossings through the rod after being reflected on the opposite end. The change in time of zero crossings is monotonically related to the immersion depth. This relative measurement method can be used in different kinds of liquids, including strong acids or bases.

Bubbly flows in a column with submerged hollow fiber membranes

Experiments of bubbly flows in a column with submerged hollow fiber membranes are carried out to discuss the relation between bubbly flow characteristics and fouling control. Two kinds of liquids, water and xanthan gum-water solution (XG-W), are used as the liquid phases. The relaxation rates of membranes are set at 0.0 or 0.5%. The number of small bubbles with ellipsoidal shapes in water are larger than that in XG-W, while large bubbles with spherical cap shapes are remarkably observed in XG-W in spite of the presence of membranes. The rate of large bubbles is enhanced in XG-W due to bubble coalescence. The gas holdup in water is higher than that in XG-W. The gas holdup becomes higher due to the presence of membranes and membrane relaxation in both water and XG-W. For discussion on fouling control due to bubbly flows, experiments are carried out to remove pseudo sludge attached to hollow fiber membranes. The relaxation of membranes enhances the removal rate of pseudo sludge. The mean removal rate, which is the mean value of the removal rate of each membrane, increases with increasing the gas holdup. This relation is well expressed by a linear regression in the present experimental range regardless of the liquid property and membrane relaxation, that is, the gas holdup has a prospect of an indicator for estimating fouling probability.

Effect of surfactants on the elasticity of the liquid-liquid interface.

We investigated the effect of surfactants on an interface between two kinds of liquids by molecular dynamics (MD) simulation. We adopted the simple bead-spring model with two atoms as the surfactants. We controlled the interfacial tension of the surfactant adsorbed on the interface by changing the bond length. Although the interface's structure changed depending on the magnitude of the interfacial tension, the interface was stable even under conditions where the interfacial tension was virtually zero. The Fourier spectrum of the fluctuations of the surface structure showed a crossover from q2 to q4 when the interfacial tension was almost zero, where q is the wavenumber. This crossover means that the bending rigidity is dominant for the restoring force when the surfactant molecules are sufficiently absorbed on the interface and the interfacial tension is almost zero, whereas the interfacial tension is dominant when the interfacial tension is a finite value.

Study on Wastewater Demulsification Technology of Crude Oil in Xinjiang Oilfield

The Second Oil Production Plant of Xinjiang Oilfield produces a large amount of highly emulsified crude oil, which has a serious impact on the subsequent oil-water separation. At present, the concentration of demulsifier has increased to 2000 mg/L, but the demulsification effect is still poor. In this paper, the source and physical properties of highly emulsified crude oil are investigated firstly. The results show that highly emulsified crude oil is composed of three kinds of liquid: (1) conventional water flooding (WF); (2) chemical flooding (CF); (3) fracturing backflow fluid (FB). Among them, high zeta potential, low density difference, high viscosity, and small emulsion particles are responsible for the difficulty in the demulsification of the WF emulsion, while the high pH value is the reason why the CF emulsion is difficult to demulsify. Therefore, systematic experiments were implemented to investigate the optimal demulsification approach towards the three liquids above. As for the WF emulsion, it was necessary to raise the temperature to 70 °C and the concentration of the demulsifier to 200 mg/L. Moreover, it was only necessary to add 200 mg/L of demulsifier to break the CF emulsion after adjusting the pH value to 7, while no extra treatments were needed to break the FB emulsion. We hope this study can provide a new insight for the treatment of emulsions in the later stage of oilfield development.

Experimental Study on a Liquid-Solid Phase-Change Autogenous Proppant Fracturing Fluid System.

In this paper, a liquid-solid phase-change autogenous proppant fracturing fluid system (LSPCAP) was proposed to solve the problems that was caused by "sand-carrying" in conventional fracturing technology in oil and gas fields. The characteristic of the new fluid system is that no solid particles will be injected in the whole process of fracturing construction except liquids. The fluid itself will transform into solid particles under the formation temperature to resist the closure stress in the fractures. There are two kinds of liquids that make up the new fracturing fluid system. One of the liquids is called phase-change liquid (PCL) which occurs in the liquid-solid phase change under the formation temperature to form solid particles. Another is called nonphase-change liquid (NPCL) which controls the dispersity and size of PCL in the two-phase fluid system. Based on the molecular interaction theory and organic chemistry, bisphenol-A epoxy resin was selected as the building unit of the PCL, and the NPCL consisted of deionized water + nonionic surfactant. The test results indicated that the new fracturing fluid shows the properties of non-Newtonian fluid and has no wall-building property. The new fluid system has good compatibility with the formation fluid, conventional fracturing fluid, and hydrochloric acid. Through the filtration test, the filtration coefficients of PCL, NPCL, and mixture are found to be 1.56 × 10-4 m/s1/2, 2.66 × 10-4 m/s1/2, and 1.7 × 10-4 m/s1/2, respectively, and the damage rate of mixture and NPCL is 18 and 17.7%. The friction test results show that the resistance reduction rate reaches 69% when the volume ratio of PCL and NPCL is 1:10. The shear rate and time only affect the size of the autogenous solid particles, and the sorting coefficient (S) of the particles is 1.04-1.73, indicating good sorting. Crushing resistance and conductivity test results show that the crush rate of autogenous solid particles is 3.56-8.42%. The conductivity of the autogenous solid particles is better than those of quartz sand and ceramsite under a pressure of 10-30 MPa.

気泡塔内大・小気泡群のボイド率に関する研究

The void fractions of large and small bubbles, αG,L and αG,S, in a bubble column were measured by means of the DGD (Dynamic Gas Disengagement) method. The column diameter was 200 mm and the initial liquid heights H0 were 800, 1600, 2400, and 3000 mm. We dealt with heterogeneous bubbly flows with the superficial gas velocity JG from 0.06 to 0.30 m/s. Three kinds of liquids were used as the liquid phase to understand effects of the liquid viscosity on the void fractions. The following conclusions were obtained: (1) an experimental database of the void fractions of large and small bubbles was obtained at various initial liquid heights and liquid viscosities, (2) the void fractions of large and small bubbles increase with increasing JG at constant H0, (3) the void fraction of large bubbles for JG ≤ 0.10 m/s decreases with increasing H0 for H0 < 2400 mm and is almost constant for H0 ≥ 2400 mm while αG,L is independent of H0 for JG ≥ 0.20 m/s, (4) the liquid viscosity does not affects αG,L, (5) the void fraction of small bubbles slightly increases at JG = 0.06 m/s, whereas it is almost constant at JG = 0.10 m/s, and decreases for JG ≥ 0.20 m/s as H0 increases, and (6) the void fraction of small bubbles decreases with increasing the liquid viscosity and dependence of αG,S on H0 is not so different.

The movement and shape change characteristics of a bubble passing through a liquid-liquid interface

In order to study the movement and shape change characteristic of bubble when passing through the interface of two kinds of liquids with different viscosity, the free rising process of a single bubble in static stratified liquids was numerically simulated with the volume-of-fluid method. The results show that, when the initial height of bubble rising is the same, the rising velocity, deformation increase with the increase of bubble radius. When the maximum intensity of the vortex in the bubble is distributed at the top of the bubble, the top of the left and right sides and the bottom of the left and right sides, the bubble shape is spherical, ellipsoid and spherical cap shape respectively. At different initial heights, the bubble trajectory shows three different shapes ? linear, spiral, and C-shaped. The relation-ship between the bubble aspect ratio and rising height is predicted when different radius bubble passing through the interface. The amount of liquid B (lower layer) carried by the bubble increases with the increase of the bubble?s initial radius, and the amount of liquid carried by bubbles in C-shaped trajectory is higher than that in spiral trajectory.

Factors to control the alignment of surface-treated titanium dioxide powders to maximize performance of sunscreens.

Titanium dioxide powders are contained in a large class of colour cosmetics and sunscreen formulas. When they are used, the formation of a uniform functional powder layer on the skin is an important factor to show their functionality, such as aesthetic and UV protection. Attempts were made to extract the factors that affect the UV shielding ability of the deposited powder layer. Seven kinds of surface treatments were conducted on nano-sized titanium dioxide powder to modify the surface characteristics. Dispersion samples were prepared by mixing these powders with liquids, such as mixed solutions of cyclopentasiloxane, isododecane, coconuts alkane and dimethicone using a disperser and a bead mill. The dispersions were applied using an applicator on cellulose triacetate film, polycarbonate film and polymethyl pentene film. Laser microscope observation and micro-gloss glossmeter analysis were carried out to assess the flatness of the deposited powder layers, and the UV shielding ability was evaluated using SPF analyser. Factors whose influences on the structure and UV shielding ability of the deposited powder layer being analysed were pseudo-HLB of the powders, liquids for preparing the dispersions and material of the substrates. Higher UV shielding ability was attained when powders having pseudo-HLB at around 6 were employed independent from the kinds of liquids and substrates. Flatness of the deposited layer was found to enhance the UV shielding ability of the UV-B region, while that of the UV-A region was scarcely influenced by the flatness. Employing lower surface tension liquids for preparing the dispersions and materials exhibiting lower polar components of surface free energy as substrates tended to enhance the UV shielding ability. Surface treatments conducted on the powders in this study were found to change UV shielding ability, especially UV-B shielding ability, and the relation between pseudo-HLB and UV shielding ability was scarcely influenced by the kinds of liquids. Both surface tension of liquids and the polar component of surface free energy of substrates affected the UV shielding ability. It was suggested that pseudo-HLB calculated based on chemical structure becomes useful information to choose optimum surface treatment to make uniform powder alignment independent from the surrounding environment.

Study on the Vibration Characteristics of the Spraying Needle Excited by Electro-hydraulic Source Based on Luminous Energy Method

When one kind of liquid was atomized by a metal needle in the electric field, violent vibration of the spraying needle could be observed clearly, and the atomizing stability was affected by it seriously. To explore the cause of the needle’s vibration and weaken its negative effect, an optical energy method was adopted and some characteristics of the vibration were investigated. The principle of the optical energy method was very simple, it was just a transformation from mechanical information of the needle’s vibration to an optical signal composed with luminous energy features and received by a photodiode. The prototype of it was composed by a luminous source system and a testing circuit cored with MCU STC89C52. After the electronic signal transferred from the luminous energy was analysed, some characteristics come from different needles under different working conditions can be obtained. Some results are: the cause of the vibration comes from dual incentives of the electrostatic field and the atomized liquid jet, in view of mechanical structure, the length and diameter of the spraying needle was the main factors affecting the vibration amplitude and frequency, considering the flow rate flow through the spraying needle, there are different starting vibration voltages for different flow rate at the same length and diameter.

Synthesis and Characterization of a Novel Self-Generated Proppant Fracturing Fluid System

Hydraulic fracturing is an important technology for the stimulation of oil and gas reservoirs. Conventional fracturing technology based on “sand-carrying” faces some challenges such as sand plugs; incompatibility with the well completion method; damage to the reservoir caused by the incomplete gel-breaking of the fracturing fluid; solid proppants inefficiently turning the corner in complex fracture networks, and so on. In this paper, a novel self-generated proppant fracturing fluid system is proposed to solve the above problems caused by “sand-carrying”. The advantage of the fracturing fluid system is that in the whole process of fracturing, no solid proppants will be injected. The fracturing fluid itself will transform into solid proppants in the induced fractures under high temperatures to resist fracture closure stress. The fluid system consists of two kinds of liquids. One is the phase change liquid (PCL), which occurs as a liquid–solid phase change at high-formation temperatures to form a solid proppant. The other is the non-phase change liquid (NPCL), which controls the dispersity of the PCL in the two-phase fluid system. The main building block of the PCL is confirmed to be the bisphenol-A diglycidyl ether-type epoxy resin, whereas the NPCL is mainly composed of surfactants. The viscosity, phase-change temperature, and time of the fracturing fluid system are, respectively, about 30 mPa·s, 80 °C, and 20 min.

Experiment of swing and deformation of a droplet on a horizontal fiber due to crosswind

The purpose of this paper is to experimentally investigate the oscillate of a clam-shell shaped droplet on a horizontal fiber by the action of crosswind, quantitatively describe the swing and deformation of the droplet, and analyze the damping force by surface tension. The dynamic images of the droplet are recorded by high-speed cameras, the profile curves in the top view and side view of droplet are both approximated to multiple ellipse arcs. Four kinds of liquids and three nylon fibers are used in the experiments. The experimental results show that the droplet oscillates periodically around the fiber by the flow drag force, the swing frequency is inversely proportional to the droplet mass, but does not increase with Re. In addition to the swing around the fiber, the droplet also oscillates periodically in the radial direction, and the frequency of radial oscillation is higher than that of circular swing, which results in the swing amplitude fluctuation. By the flow pressure, the windward side and the leeward side of the droplet deform asymmetrically, the difference of surface tension force on both sides of the droplet forms a moment against the droplet swing around fiber, the resistance moment increases with the liquid surface tension coefficient and fiber diameter.

Perbedaan Kekerasan Resin Modified Glass Ionomer Cement dan Kompomer pada Pengguna Obat Kumur Alkohol dan Non Alkohol

The restoration materials, Resin Modified Glass Ionomer Cement and compomer, often contact with various kinds of liquid in oral cavity. One of the liquid which has contact in oral cavity was mouthwash. The effect of using mouthwash can affect the hardness of the material. Hardness affects the longevity of a filling material persisted in the oral cavity. This study aims to determine the difference in hardness between Resin Modified Glass Ionomer Cement and compomers on the users of alcohol and non alcoholic mouthwash. The type of the research is quasi experimental. There are 36 samples (18 RMGIC and 18 compomers). Each ingredient was divided into two groups which were immersed in alcoholic and non alcoholic mouthwashes. Then, the samples were immersed for 5 days which were replaced every 24 hours. The sample hardness was measured by the Vickers Hardness Test (Shimadzu HMV-M3). Data were analyzed using the Kruskal Wallis test. After being tested, the average results of the non alcohol compomer hardness were 31.89, 22.94 alcoholic compomers, 14.17 non alcoholic RMGIC, and 5.00 alcoholic RMGICs. The Kruskal Wallis analysis test results obtained p value &lt;0.5 showed there is a significant difference. There is a significant differencein the hardness of the Resin Modified Glass Ionomer Cement (RMGIC) and the compomer on the users of alcohol and non alcoholic mouthwash. The hardness from highest to lowest is compomers immersed in non alcoholic mouthwash, compomers in alcoholic mouthwash, RMGIC in non alcoholic mouthwash, and RMGICs in alcoholic mouthwash.

Preparation and Evaluation of PDMS/Carbon Soot Particles Superhydrophobic Biomimetic Composite Coating with Self-Cleaning and Durability.

In this paper, a superhydrophobic biomimetic composite coating was fabricated on brass by electrochemical etching, brushing PDMS adhesive layer, and depositing carbon soot particles. Due to the microstructure and the optimized ratio of PDMS, the contact angle of the superhydrophobic coating is up to 164° and the sliding angle is only 5°. The results of optical microscopy and morphometric laser confocal microscopy show that the prepared coating surface has a rough hierarchical structure. A high-speed digital camera recorded the droplet bouncing process on the surface of the superhydrophobic coating. The self-cleaning property of the coatings was evaluated by applying chalk dust particles as simulated solid contaminants and different kinds of liquids (including grape juice, beer, cola, and blue ink) as liquid contaminants. The coating remained superhydrophobic after physical and chemical damage tests. This work presents a strategy for fabricating superhydrophobic biomimetic composite coatings with significant self-cleaning properties, durability, and shows great potential for practical engineering applications.

Universal ultra-sensitive refractive index sensor based on an integrated SiO2 asymmetric Mach-Zehnder interference filter (AMZIF)

This paper proposes an integrated universal ultra-sensitive refractive index sensor that is applicable for many kinds of liquid. The sensor is SiO2 asymmetric Mach-Zehnder interference filter (AMZIF) with a reference window and a sensing window on different arms. The formula derivation shows that the sensitivity of AMZIF is directly proportional to the arm length, and its measurement range can be expanded by reducing the diffraction order. The sensor is fabricated using standard planar lightwave circuit (PLC) technology, and the tested sensitivity reaches 21193.3 nm per refractive index unit (nm/RIU). With appropriate reference material, the universal AMZIF sensor can measure the refractive index of any liquid whose refractive index is between 1.33 ∼ 1.45 and the sensitivity remains above 20000 nm/RIU.

Ethanol drop impingement on ultracold surfaces under low-temperature cold-start conditions of engines

Spray impingement on ultracold surfaces is a key factor that affects the cold start performance of an internal combustion engine in some high latitudes and high altitudes regions, whose environment temperature could reach −40 °C. Ethanol is selected as the test liquid considering the real fuel properties in engines, and the specific drop splashing and the film spreading process on ultracold surfaces are investigated comprehensively in this work. Splashing process becomes more severe on the surfaces at −30 °C, accompanied by more and faster secondary droplets produced during the impingement. The film spreading process does not differ significantly on the surfaces of different temperatures during the early spreading phase (τ≤1). An improved dimensionless spreading factor βn≡D/D0/Re0.2 is proposed to describe the spreading dynamics in this stage, and a better convergence is achieved among the comprehensive experiments regarding different kinds of liquids and surface temperatures. In the later spreading phase, liquid film spreads faster on warmer surfaces and retracts slightly after reaching its maximum spreading factor βmax on a room-temperature surface. However, the liquid film on cold surfaces will keep stretching for a much longer time and finally obtains a larger βmax. An improved model is established to predict the βmax under the comprehensive conditions. Specific assumption and treatment are applied in the model considering the operating conditions of the internal combustion engines. The model provides a good prediction of the maximum spreading factors under different surface temperatures.

Investigation of partially transparent and high-density two-phase liquids using laser interference method

The purpose of the present work was to investigate partially transparent and high-density two-phase liquids using the laser interference method to establish the limits of applicability of this method. The results of the work include the interference fringe patterns of drops when using various kinds of liquids, the calculated drop sizes. The calculation of inaccuracies was also carried out to further establishing the limits of applicability of this method.

Evaporation and heat transfer characteristics of CO2, CF4 and CO2/CF4 on [formula omitted], [formula omitted] and [formula omitted] surfaces

This paper investigated the evaporation processes of CO2, CF4, and CO2/CF4 on ZnO(101¯0),ZnO(0001) and ZnO(112¯1) surfaces and the heat transfer characteristics during the evaporation. The molecular dynamics simulations are conducted under atmospheric conditions with 145 K, 195 K and 260 K. The results showed that the evaporation of the three kinds of liquids are the highest on ZnO(112¯1) substrate but the lowest on ZnO(0001) substrate. The evaporation response of CO2 to the temperature has a delay effect compared with that of CF4 and CO2/CF4 mixture. Furthermore, the heat flux fluctuates during the initial evaporation stage, and the temperature increase is more obvious to accelerate the heat transfer balance of CF4/ZnO and mixture/ZnO systems. The number of evaporated CF4 particles in the CO2/CF4 mixed system is higher than that in the pure system, indicating that the presence of CO2 will promote the evaporation of CF4. The boiling phenomenon was found for the systems containing CF4 molecules when the temperature is higher than the phase transition temperature, and the bubbles appeared earliest when ZnO(101¯0) was used as the substrate which makes the heat flux jump obviously in the initial evaporation stage. This study provides insight into the evaporation and heat transfer properties of liquid/solid system with ZnO as the substrate.