辛基磷酸酯钠盐的合成及其在渗透剂中的应用

介绍了辛基磷酸酯钠盐的合成,确定了较佳的工艺条件,测试了该产品及由其组成的渗透剂的性能,指出该产品是耐碱渗透剂的理想组分之一。     

Wetting behavior and bonding characteristics of bismuth-based glass brazes used to join Li-Ti ferrite systems

A series of bismuth-based glass brazes were used to join Li-Ti ferrite. The wetting behavior and bonding characteristics of glass brazes utilized to join Li-Ti ferrite were systematically investigated. The glass brazes feature a good CTEs match, and a favorable wetting ability over Li-Ti ferrite mating surfaces. Upon brazing, the Bi-rich phases (Bi₄₆Fe₂O₇₂, Bi₁₂SiO₂ and Bi₂₄B₂O₃₉) and Zn-rich phase (ZnO) were observed in the Li-Ti ferrite/Bi40 and Li-Ti ferrite/Bi35 joints. The Zn₂SiO₄, ZnFe₂O₄ and Bi₅Ti₃FeO₁₅ whiskers were detected in the Li-Ti ferrite/Bi25, Li-Ti ferrite/Bi20 and Li-Ti ferrite/Bi25-BC joints, respectively. No crystalline phase was detected in the Li-Ti ferrite/Bi30-BF joint. Multiple factors impact the joint strength, such as the three-point bending strength of glass brazes, the CTE match of the glass braze and the Li-Ti ferrite, as well as the crystal phases within the seam. The joint strength has the maximum value of 86 MPa for a Li-Ti ferrite/Bi25-Ba couples. The main impact is attributed to the strengthening effect of Bi₅Ti₃FeO₁₅ whiskers. The dielectric properties of Li-Ti ferrite/glass braze joints show a stronger frequency dependence than that of Li-Ti ferrite at low frequency. This is attributed to the formation of new interfaces. The glass matrix or a crystal phase with a higher dielectric constant could counteract the decrease in the dielectric constant of heat-treated Li-Ti ferrite. Therefore, the dielectric constant of joint, especially that of Li-Ti ferrite/Bi25-BC joint, would be near that of the original Li-Ti ferrite at a high frequency. Meanwhile, no increase in the dielectric loss tangent of a joint takes place.     

Wetting of plasma-sprayed coatings of SrAl2Si2O8 (SrASi), BaAl2Si2O8 (BASi) and Sr4Al6O12SO4 (SAlSr) by Al-12Si alloy

The wettability of SrAl₂Si₂O₈ (SrASi), BaAl₂Si₂O₈ (BASi) and Sr₄Al₆O₁₂SO₄ (SAlSr) plasma-sprayed coatings on mullite substrates by an Al-12Si alloy at 1000 °C was studied using the sessile drop technique. All the coatings showed high adherence to the substrate. The SrASi and BASi coatings were mainly amorphous with some monoclinic crystallites of SrAl₂Si₂O₈ and BaAl₂Si₂O_8, respectively. The SAlSr coating was amorphous and contained Sr, Al and O, indicating a decomposition during the coating process. The average contact angles for BASi, SrASi and SAlSr coatings were 121, 122 and 124°, respectively, showing a non-wetting behavior. Coatings of BASi and SAlSr after the wetting experiments presented no reaction with aluminum, while the SrASi coating showed the formation of an alumina layer as a reaction product, indicating a slight reduction of the Sr-celsian by aluminum. In general, these coatings are suitable to enhance the corrosion resistance of aluminosilicate ceramics in contact with Al alloys.     

STABILITY OF THE LENSLIKE LIQUID THICKENING (THE DROP) ON A SOLID SUBSTRATE

The quasi equilibrium of a liquid lens or a liquid drop on a solid substrate is considered on the basis of the thermodynamics of microscopic thin liquid films. Both contact angles, corresponding to the membrane model and to the finite thickness layer convention of the film, have been derived as a function of the disjoining pressure isotherm. The analytical expressions for the line tension terms have been obtained, and the criterion for the stability of a liquid drop on a solid substrate has been proposed.     

Enhanced wetting properties of silicon mesh microchannels coated with SiO2/SnO2 nanoparticles through layer-by-layer self assembly

The enhanced wetting property of silicon mesh microchannels coated with SiO₂/SnO₂ nanoparticles is presented in this paper. The SiO₂/SnO₂ bi-layers are prepared using layer-by-layer nano self assembly. It is found that the silicon mesh microchannels are super hydrophilic and demonstrated powerful capillary. The capillary rise rate is characterized by measuring the front location of liquid on the silicon mesh surface, laid on a 45° inclined platform. For a silicon mesh sample with an overall dimension of 25 mm × 25 mm, when the microchannel width is 0.5 mm, the liquid front can reach the top edge of the sample in approximately 30 s. The mesh silicon surface with a SiO₂/SnO₂ multilayer film presented in this paper has better wettability and higher capillary pressure than other hydrophilic surfaces reported. The results provide a new way to improve the capillary in microchannels with enhanced super hydrophilic surfaces in microchannels for variety of micro/nanofluidic applications.     

Investigation of Interfacial Tension Reduction,Wettability Alteration,and Oil Recovery Using a New Non-ionic Oil-Based Surfactant from Gemini Surfactants Family Coupled with Low-Salinity Water: Experimental Study on Oil-Wet Carbonate Rock

Low-salinity surfactant (LSS) flooding is a combined enhanced oil recovery (EOR) technique that increases oil recovery (OR) by altering the rock surface wettability and reducing oil–water interfacial tension (IFT). In this study, optimum concentrations of several types of salt in distilled water were obtained on the basis of IFT experiments for the preparation of low-salinity water (LSW). Then, a new oil-based natural surfactant (Gemini surfactant, GS) was combined with LSW to investigate their effects on IFT, wettability, and OR. Experimental results showed that LSW is capable of reducing IFT and contact angle, but the synergy of GS and the active ions Mg²⁺, Ca²⁺, and SO₄²⁻ in LSW was more effective on IFT reduction and wettability alteration. The combination of 1000 ppm MgSO₄ and 3000 ppm GS led to a decrease in contact angle from 134.82° to 36.98° (oil-wet to water-wet). Based on core flooding tests, LSW injection can increase OR up to 71.46% (for LSW with 1000 ppm MgSO₄), while the combination of GS and LSW, as LSS flooding, can improve OR up to 84.23% (for LSS with 1000 ppm MgSO₄ and 3000 ppm GS). Therefore GS has great potential to be used as a surfactant for EOR.     

Influence of Acrylic Adhesive Viscosity and Surface Roughness on the Properties of Adhesive Joint

In adhesion, the wetting process depends on three fundamental factors: the surface topography of the adherend, the viscosity of the adhesive, and the surface energy of both. The aim of this paper is to study the influence of viscosity and surface roughness on the wetting and their effect on the bond strength. For this purpose, an acrylic adhesive with different viscosities was synthesized and some properties, such as viscosity and surface tension, were studied before adhesive curing took place. Furthermore, the contact angle and the lap-shear strength were analyzed using aluminum adherends with two different roughnesses. Scanning electron microscopy was used to determine the effect of the viscosity and the roughness on the joint interface. The results showed that the adhesive exhibits an optimal value of viscosity. Below this value, at low viscosities, the low neoprene content produces poor bond strength due to the reduced toughness of the adhesive. Additionally, it also produces a high shrinkage during curing, which leads to the apparition of residual stresses that weakens the interfacial strength. However, once the optimum value, an increase in the viscosity produces a negative effect on the joint strength as a result of an important decrease in the wettability.     

Contact Angle of Ethanol and n‐Propanol Aqueous Solutions on Metal Surfaces

The contact angles of the aqueous solution of ethanol and that of n‐propanol on copper, aluminum, and stainless steel surfaces are reported. The contact angles were measured under atmospheric conditions, and then under vapor‐liquid equilibrium conditions at 1 atm and different temperatures. The results showed the variations of the contact angles with the concentrations of aqueous solutions on different metal material surfaces with different roughness. Some unstable behavior of the wetting ability around the azeotropic point of a binary solution is reported. Influences of concentration, kind of materials, and the surface roughness on the wetting ability are discussed. The model for predicting the contact angle of alcohol aqueous solutions on metal surfaces under atmospheric and vapor‐liquid two‐phase equilibrium conditions at 1 atm is derived from the Young equation.     

纳米碳酸钙表面改性的初步研究

应用几种脂肪酸对纳米碳酸钙进行表面处理，对它们的改性效果进行了比较，透视电镜（TEM）分析结果表明：改性纳米碳酸钙粒子在乙醇中的分散性得到了提高；图像分析显示；改性碳酸钙颗粒的粒径分布有所改善；润湿性测定结果预示：改性粒子与聚合物将具有较好的相容性和亲和性。     

Investigation of wetting behavior of Cr–Mn–Ni steels on hBN-SiC-ZrO2-substrate

The present study investigates the wetting behavior of Cr–Mn–Ni-alloys with TRIP/TWIP-effects on the hBN-SiC-ZrO₂-substrate using the sessile drop method. The wetting behavior was studied in a 90 vol% N₂/10 vol% H₂ atmosphere in the temperature range of 1500 °C–1600 °C. Experiments were conducted in the reactive steel/ceramic system. Results demonstrate the effect of the nickel and the sulfur content on the contact angle between hBN-SiC-ZrO₂-substrates and Cr–Mn–Ni-alloys. The increase in the nickel content from 3 to 9 mass% caused the increase of the contact angle from 129 to 138° at 1600 °C. Whereas, the increase in the sulfur content caused the decrease of the contact angle. The contact angle of the melts alloyed with the sulfur increases as the temperature rises. The increase in the contact angle was related to the evaporation of the manganese. In addition, the study discusses the chemical reaction between the hBN-SiC-ZrO₂-substrate and Cr–Mn–Ni-alloys through (i) SEM-EDX investigations and (ii) thermodynamic calculations. The SEM-EDX analysis of the steel/ceramic interface shows the chemical degradation of the hBN-SiC-ZrO₂-substrate. As a result of the reaction, a transition layer with a thickness of around 0.7 mm was formed in the hBN-SiC-ZrO₂-substrate. To characterize the chemical reaction, thermodynamic calculations were conducted using the Thermo-Calc software. Results show that the chemical reaction was caused by the chemical instability of the SiC with regard to elements in Cr–Mn–Ni-alloys.