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This study focuses on the smoothly blending problem of two cylinders whose axes are non-coplanar at the clipping planes which are perpendicular to the axes. Based on the condition that the axes were smoothly blended, we presented the necessary and sufficient conditions of the existence of the blending surface with the cylindrical helicoids tube constructed. And when those conditions were met, we presented the specific blending examples.

Under the acidic condition, 6-gingerol (C17H26O4) reacted with hydroxylamine to generate 6-gingerol oxime (C17H27NO4). Single-crystal X-ray diffraction with CuKα radiation (λ = 1.54184 Å) revealed the crystal belongs to the orthorhombic system, the space ground is P212121 with a = 5.24240(10), b = 25.7792(4), c = 25.9824(5) Å, V = 3511.39(11) Å3, Z = 8, Mr = 309.40, Dc = 1.171mg/mm3, μ = 0.669mm-1, S = 1.035, F(000) = 1344.0, the final wR2 was 0.1132 (all data) and R1 was 0.0412 [I>2σ (I)]. Two molecules compose one monomeric unit in the crystal. And the hydrogen bonds construct the dimer and the integral crystal spacial structure. The antioxidant activity of the 6-gingerol oxime was tested by the scavenging effect on DPPH radical and potassium ferricyanide reducing power test while Vitamin C was regarded as the comparison. The IC50 of the oxime for the scavenging effect on DPPH was 0.0471 g/L which was less strong than Vitamin C. The reducing power of Vitamin C was about three times powerful than the 6-gingerol oxime.

A novel method is proposed by constructing the intersecting line of two tapered surfaces to smooth blending non-coplanar axes. Necessary and sufficient conditions for smooth blending two non-coplanar cylindrical surfaces are achieved. Specific example is also provided.

In this paper, a three-dimension model for the vanadium redox flow battery was established to simulate its mass transfer. The distribution of VO2+and VO2+ in positive electrode area, the distribution of V2+ and V3+ in the negative electrode area, and the influences of flow velocity, temperature and the electrolyte concentration on the mass transfer are analyzed. The results show that the mass fraction of VO2+ and V2+ decrease while those of VO2+and V3+increase along the channel direction; the species concentration under the ridge is lower than that under the flow channel. The flow velocity of electrolyte affects the mass distribution at the entrance of the cell, and hardly affects the electrochemical reaction rate; Increase of the temperature accelerates the electrochemical reaction rate; the electrolyte concentration affects both of the mass distribution and the number of ions. The study has great significance both on the optimization of vanadium redox flow battery and its application.

This paper studies the smoothly blending problem of two elliptic cylinders whose axes are non-coplanar at sections where they are perpendicular to axes. Based on conditions of smoothly blending axes, we acquire necessary and sufficient conditions of existing blending surface by constructed elliptic cylindrical helicoid tube. And when we meet those conditions, the specific blending examples will be provided.

A large number of oilfield produced water is produced during the developing of oilfield，the optimal way to process these oilfield produced water is to reinject it into strata. This paper firstly analyzes the characteristics of oilfield produced water, then focuses on introducing the research and application process of both traditional and new treatment technologies of produced water , and finally brings forward some expectation about the application and development direction of the oilfield produced water treatment processes.

Paper illustrates the background of boutique open video class in China. According to the prepared works of the photographers and the subjects before we taped of the boutique open video classes in the teaching field of China, it researches the techniques which are used in recording video and later editing. It mainly discusses the problems, such as one third composition methods, cutting-body principle, lens push-pull shooting technologies and the photography technology problems and so on. It also studies the forming strategy of the online open classes initiated by foreign distinguished universities.

The paper illustrates the background of boutique open video class in China, and the differences between the boutique open video class and the boutique shared class. It also discusses the domestic study of the strategy of forming the online open courses initiated by foreign distinguished universities in recent years. By the comparison of the strategy used at home and abroad in terms of equipment, shooting techniques, and multimedia technology utilization, it draws the revelation of producing boutique video open classes.