In this paper, the technology of ultrasonic extraction of flavonoids from grapefruit seed was studied. The orthogonal design method was used to optimize the process. The results showed that the optimum extraction parameters were ultrasonic ratio 1:50 (g / mL) , Ultrasonic power of 280w, extraction temperature...

In order to verify the antioxidant activity of Litsea cubeba oil, the antioxidant activity of Litsea cubeba oil was determined by DPPH method. The experimental results showed that: Shancang The DPO free radical scavenging rate of Litsea cubeba oil was 86.33% at the concentration of 2.5mg / mL. Therefore,...

from the construction and planning, virtual experiment model of experimental pattern construction, environmental protection and construction of experimental model of innovative experimental building aspects in detail, this article gives better guide and improvement on the electrical and electronic professional...

The application of BIM technology in the field of construction accelerates the construction industry to the rapid changes in information technology, and promote the level of China's construction to the height of the development of new technology, it can be said that BIM plays an important role in the...

The open economy is not only the development of export, and encourage imports, paying attention to the two-way flow of production factors, emphasizing the competition and economic form of cooperation between countries or regions, which means it not only focus on the domestic market, but also pay attention...

The use of building decoration materials in the interior design are discussed, expounds the concrete application mode of stone and wood, glass fiber, fabric and ceramic materials in the interior design, and it puts forward innovative ways of building decoration materials in the interior design, in order...

The theory of the basic education reform of mathematics skills research put forward higher requirements, and there is urgent need to reform the mathematics curriculum design, this paper puts forward a theoretical discussion of the mathematical skills to provide a reference for the improvement of math...

The construction project audit function is to make the construction more standardized , so the construction project audit is to strengthen the audit and supervision functions of the economic, scientific and reasonable construction project audit which is conducive to improve efficiency in the use of funds....

Based on the traditional teaching system formed in music schools, different teachings between schools produced making individual students unable to get targeted teaching, this is one of the reasons leading to the effectiveness of the vocal music teaching which is not high. The shortage and difference...

This paper uses the principle and method of simplifying the urban waterlogging model to set up a model of waterlogging problem in a horizontal bridge of Changchun. This model is combined with the precipitation data from 1950 to 2010 in Changchun City, and the probability of waterlogging risk at the bottom...

In mathematical analysis, the problem of series summation plays an important role, and it is also the difficulty of mathematical analysis. In general, the solution to the series summation is obtained by the method of item by integration, definition, or item differentiation. In this paper, through the...

The generating principle of skew bevel gear tooth face is analyzed about spherical involute, base cone and base plane that tangent to the base cone is constructed. Firstly, based on the relevant motion between the base cone and the generating line in the generating process of tooth surface, a new machining...

With the improving of the quality of people's life level, people for lighting design media design requirements are more strict, a lighting in commercial space has gradually become an indispensable important constituent, is extensively used in business. Therefore, by the lights of the scientific and effective...