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41.
Tian Maozhang Song Xinmin Ma Desheng Wang Qiang Zhang Qun Wenli Luo 《Journal of Dispersion Science and Technology》2016,37(5):706-714
Transition from oil-in-water (O/W) emulsions to water-in-oil (W/O) emulsions and its action on enhanced oil recovery was investigated by viscosity, morphology, and simulated flooding experiments. This transition can be realized by increasing the volume ratio of oil to water or decreasing the emulsifier concentration. At a mass concentration of 0.3 wt%, the self-developed emulsifier FJ-1 mainly forms O/W emulsions at a volume ratio (oil to water) of 1:1. The emulsions behave as O/W emulsions with a low viscosity when the volume ratio of oil to water is below 2:1. Above 2:1, increasing volume ratio leads to the O/W emulsions transferring into W/O emulsions with high viscosity. For example, at a volume fraction of 4:1, the viscosity of W/O emulsions reaches 229.1 mPa · s, and separated water can hardly be detected. Transition from O/W emulsions to W/O emulsions with high viscosity can also be realized by decreasing the concentration of emulsifier to 0.05 wt% or lower at a volume ratio of 1:1. These may be the critical factors leading to transition from O/W emulsions to W/O emulsions at core conditions. Simulated flooding experiments show that emulsifier fluids can act as an in situ mobility improver and make an improvement of oil recovery even by 20.4%. The results indicate that the water-in-crude-oil emulsions possess great potential in enhancing oil recovery. 相似文献
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Starting with the QCD generating functional, a new derivation and a new form of the Dirac-Schriidinger (D-S) equation,catisfied by the equal-time Bethe-Salpeter amplitude of quark-antiquark bound states have been given. In this equation, the effective interaction kernel has a compact expression and can be directly calculated by means of the conventional QCD Feynman rules. F'urthermore, an equivalent reduction of the above equation to a Pauli-Schriidinger equation has also been achieved and a closed form of the effective interaction Hamiltonian appearing in the latter equation has been explicitly written out. 相似文献
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基于光时域反射技术与缠绕式光纤传感阵列的结构状态监测方法 总被引:4,自引:0,他引:4
提出了一种新颖的、利用多模光纤缠绕钢绳式的传感阵列网络, 对智能材料与结构的受力、应变等状态参量进行了监测和估计, 并采用了光时域反射技术实时处理并行分布式传感信号, 给出了测试数据、识别结果 相似文献
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柱前荧光衍生-高效液相色谱法测定尿和血清中的环境雌激素 总被引:8,自引:0,他引:8
建立了同时测定人尿和血清中环境雌激素双酚A、4-壬基酚、17α-乙炔基雌二醇及内源性雌激素雌三醇、17α-雌二醇和17β-雌二醇的对硝基苯甲酰氯柱前荧光衍生-高效液相色谱测定方法。尿样经酸水解、固相萃取柱浓缩、净化分离;血清样品经乙腈沉淀蛋白后,用乙醚萃取游离态雌激素,N2气流挥干、在无水条件下,雌激素与对硝基苯甲酰氯反应生成荧光产物,用高效液相色谱法定量。检出限为2.7—8.3μg/L;加标回收率尿样为78.0%-102.5%,血清样为72.6%-98.6%;方法精密度为1.29%-4.52%。应用本法对20份尿样和10份血清样进行了测定,结果满意。 相似文献
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A numerical generation method of hyperspherical harmonics for tetra-atomic systems, in terms of row-orthonormal hyperspherical coordinates-a hyper-radius and eight angles-is presented. The nine-dimensional coordinate space is split into three three-dimensional spaces, the physical rotation, kinematic rotation, and kinematic invariant spaces. The eight-angle principal-axes-of-inertia hyperspherical harmonics are expanded in Wigner rotation matrices for the physical and kinematic rotation angles. The remaining two-angle harmonics defined in kinematic invariant space are expanded in a basis of trigonometric functions, and the diagonalization of the kinetic energy operator in this basis provides highly accurate harmonics. This trigonometric basis is chosen to provide a mathematically exact and finite expansion for the harmonics. Individually, each basis function does not satisfy appropriate boundary conditions at the poles of the kinetic energy operator; however, the numerically generated linear combination of these functions which constitutes the harmonic does. The size of this basis is minimized using the symmetries of the system, in particular, internal symmetries, involving different sets of coordinates in nine-dimensional space corresponding to the same physical configuration. 相似文献