A method is provided for determining the surface viscosity of a liquid in which a thread is formed from a drop of the liquid. The thread is lengthened and its minimum radius h.sub.0 is determined at multiple times between the thread formation and thread pinch-off. The minimum radius and associated time values are used to determine a linear relationship of minimum radius and time, with the coefficient of the linear relationship, or the slope X of the line in the linear relationship, corresponding to the surface viscosity μ.sub.s of the liquid according to one of the following equations:

[00001]$\begin{array}{cc}x=\frac{0.0709}{1+5B_{\mathrm{s0}/3h_0}},& \left(1\right)\end{array}$

where B.sub.s0=μ.sub.s/μR in which h.sub.0 is defined as above, R is the dimension of the feature on which the drop is provided and μ is the bulk viscosity of the liquid, or

[00002]$\begin{array}{cc}x=\frac{0.0304}{\mathrm{Oh}\left(1+5b_{\mathrm{s0}/3h_0}\right)},& \left(2\right)\end{array}$

in which Oh=μ/√{square root over (ρRσ)}, where μ and R are as defined above, ρ is the density of the liquid, and σ is the surface tension of the liquid without surfactants.

A method is provided for determining the surface viscosity of a liquid in which a thread is formed from a drop of the liquid. The thread is lengthened and its minimum radius h.sub.0 is determined at multiple times between the thread formation and thread pinch-off. The minimum radius and associated time values are used to determine a linear relationship of minimum radius and time, with the coefficient of the linear relationship, or the slope X of the line in the linear relationship, corresponding to the surface viscosity μ.sub.s of the liquid according to one of the following equations:

[00001]$\begin{array}{cc}x=\frac{0.0709}{1+5B_{\mathrm{s0}/3h_0}},& \left(1\right)\end{array}$

where B.sub.s0=μ.sub.s/μR in which h.sub.0 is defined as above, R is the dimension of the feature on which the drop is provided and μ is the bulk viscosity of the liquid, or

[00002]$\begin{array}{cc}x=\frac{0.0304}{\mathrm{Oh}\left(1+5b_{\mathrm{s0}/3h_0}\right)},& \left(2\right)\end{array}$

in which Oh=μ/√{square root over (ρRσ)}, where μ and R are as defined above, ρ is the density of the liquid, and σ is the surface tension of the liquid without surfactants.

A method for determining a contact angle of a hydrocarbon on a rock surface, the method including injecting a first brine fluid into a test cell, the first brine fluid having an initial ionic composition, injecting a hydrocarbon fluid into the test cell, contacting the hydrocarbon fluid with the first brine fluid, forming a droplet, measuring the contact angle of the hydrocarbon fluid, at least partially displacing the first brine fluid with an inert gas, measuring a ionic composition of the displaced first brine fluid in an ionic chromatograph, and comparing the measured ionic composition to the initial ionic composition.

A method for determining a contact angle of a hydrocarbon on a rock surface, the method including injecting a first brine fluid into a test cell, the first brine fluid having an initial ionic composition, injecting a hydrocarbon fluid into the test cell, contacting the hydrocarbon fluid with the first brine fluid, forming a droplet, measuring the contact angle of the hydrocarbon fluid, at least partially displacing the first brine fluid with an inert gas, measuring a ionic composition of the displaced first brine fluid in an ionic chromatograph, and comparing the measured ionic composition to the initial ionic composition.

A method for determining interfacial tension of a hydrocarbon in a brine fluid, the method including injecting a first brine fluid into a test cell, the first brine fluid having an initial ionic composition, injecting a hydrocarbon fluid into the test cell, contacting the hydrocarbon fluid with the first brine fluid, forming a droplet, measuring the interfacial tension of the hydrocarbon fluid in contact with the first brine fluid, at least partially displacing the first brine fluid with an inert gas, measuring a ionic composition salinity of the displaced first brine fluid in an ionic chromatograph, and comparing the measured ionic composition salinity to the initial ionic composition.

A method for determining interfacial tension of a hydrocarbon in a brine fluid, the method including injecting a first brine fluid into a test cell, the first brine fluid having an initial ionic composition, injecting a hydrocarbon fluid into the test cell, contacting the hydrocarbon fluid with the first brine fluid, forming a droplet, measuring the interfacial tension of the hydrocarbon fluid in contact with the first brine fluid, at least partially displacing the first brine fluid with an inert gas, measuring a ionic composition salinity of the displaced first brine fluid in an ionic chromatograph, and comparing the measured ionic composition salinity to the initial ionic composition.

A method of obtaining a numerical model is disclosed. The numerical model correlates estimated line width values to minimum pressure for gas bubble generation (MPGBG) values. An MPGBG value of each capillary tube in the reference group is measured for a liquid. A nanoparticle composition is deposited, under standard conditions, on substrate(s) from each respective reference capillary tube, to form nanoparticle lines. A line width of each of the nanoparticle lines deposited using each respective reference capillary tube is measured by a microscope apparatus. A numerical model that correlates estimated line width values to MPGBG values for the liquid is calculated.

A method of obtaining a numerical model is disclosed. The numerical model correlates estimated line width values to minimum pressure for gas bubble generation (MPGBG) values. An MPGBG value of each capillary tube in the reference group is measured for a liquid. A nanoparticle composition is deposited, under standard conditions, on substrate(s) from each respective reference capillary tube, to form nanoparticle lines. A line width of each of the nanoparticle lines deposited using each respective reference capillary tube is measured by a microscope apparatus. A numerical model that correlates estimated line width values to MPGBG values for the liquid is calculated.

A magnetic pole part, a fiber-reinforced material, a test apparatus therefor, and a control method for the test apparatus. The test apparatus comprises: a container provided with an adhesive agent container therein for containing an adhesive agent; a positioning member for positioning a member to be tested inside the container and partially inside the adhesive agent container; an adhesive agent heating member 912) for heating the adhesive agent; and an adhesive agent temperature sensor for measuring the temperature of the adhesive agent; a controller for turning on or off the adhesive agent heating member according to a temperature signal detected by the adhesive temperature sensor so as to keep the adhesive agent in the adhesive agent container at a preset temperature.

A magnetic pole part, a fiber-reinforced material, a test apparatus therefor, and a control method for the test apparatus. The test apparatus comprises: a container provided with an adhesive agent container therein for containing an adhesive agent; a positioning member for positioning a member to be tested inside the container and partially inside the adhesive agent container; an adhesive agent heating member 912) for heating the adhesive agent; and an adhesive agent temperature sensor for measuring the temperature of the adhesive agent; a controller for turning on or off the adhesive agent heating member according to a temperature signal detected by the adhesive temperature sensor so as to keep the adhesive agent in the adhesive agent container at a preset temperature.