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Existing air purifiers are mostly indoor air circulation, and most of them cannot achieve indoor and outdoor air circulation and provide fresh air to room. At the same time, the current air purifier filter on the market after absorbing a large amount of dust and other pollutants, if not replaced in time, is likely to cause secondary pollution. In response to these problems, this paper carried out an exploratory research that can achieve indoor and outdoor air purification device. According to the clean air volume of HEPA filter, the pressure of fan and the cross-sectional area of filter are determined, meanwhile, the air resistance of indoor and outdoor circulating air purifier, the effect of air blower on air purification efficiency and filter CADR are discussed in detail. According to the filtering characteristics of single-layer filter, a kind of indoor and outdoor circulating air purifier-single-layer filter type air purifier was designed. Among the air purifier, the PLC control circuit is used to achieve single-layer filter air purifier filter automatically replace.

The selection of mobile phase is significant for the separation result of HPLC, for it may have influence on the quantitative analysis. During HPLC analysis, engineers usually use (water-acetonitrile) mobile phase system to separate aldehydes and ketones, however, the existence of acetone will affect the separation effect of other substances. The paper researches one new (water-acetonitrile-tetrahydrofuran) mobile phase system to separate aldehydes and ketones. By analyzing the standard curves and test results of unknown samples, the new mobile phase can meet the analyzing needs, also it can eliminate the influence of acetone in the analysis process. What’s more, the paper uses molecular simulation[1–3] (MS) to calculate the interactions between the mobile phase and the aldehydes and ketones, mean square displacement value (MSD) and radial distribution function value (RDF), and the separation phenomenon can be well explained. In this paper, MS technology is first proposed for the development of new mobile phase, which can predict new unknown mobile phase, improve the efficiency of method development, also it can benefit the accurate qualitative analysis and prediction of peak out behavior of unknown substances.

The digital sharing of agricultural scientific and technological resources is the key to promoting agricultural scientific and technological innovation. Explore the strategic mechanism for the digital sharing of agricultural scientific and technological resources, reveal the law of their behavioral evolution, and provide theoretical guidance for the practice of digital sharing of agricultural science and technology resources. Introducing the perspective theory of perceived utility to replace expected utility, constructing a stochastic evolutionary game model for the sharing parties and demand parties of agricultural science and technology resources, analyzing the dynamic evolution rules of both sides of resource sharing, and analyzing the key factors affecting the stability of agricultural science and technology resource sharing through numerical simulation.

Power grid enterprises play an important role in China’s national economic construction and assume important social and economic responsibilities. With the further deepening of the reform of the power system, how to accurately grasp the new development stage, implement the new development concept, and build a new development pattern put forward new tasks and requirements for internal audit work, do a good job in the regular “economic examination” work, and realize the value added of internal audit, Accelerate the implementation of the strategic objective of “an international leading energy Internet enterprise with Chinese characteristics" and the development layout of “one body and four wings”, and play an important audit role for the high-quality development of power grid enterprises.

The paper discusses the numerical solution of the one-dimensional radially axi-symmetric non-linear second-order differential equation to model the conduction and radiation transfer through a spherical domain as a result of an exothermic heat source. The equation is transformed to a non-dimensional form. The dimensionless numbers emanating from the transformation represent the effect of the reaction rate, reaction type, activation energy, radiation and the convection on the temperature. The non-dimensional differential equation for the temperature distribution was previously solved using the Runge-Kutta-Fehlberg method coupled with a Shooting technique. In this paper the solution of the non-dimensional differential equation using an iterative Galerkin finite element method approach employing the Picard method is described. The commercial finite element code Comsol is also employed to solve the non-dimensional differential equation. The current study was motivated by inconsistencies that were observed in the previous results that were presented. Although the assumed underlying physics is used to evaluate the results, the study focuses purely on the numerical solution of the non-dimensional differential equation. The results obtained by the Galerkin finite element code and Comsol were found to be in exact agreement and also exhibit no inconsistencies.

Space layout design is one of the most important phases in architectural design, and current studies have shown that it can affect building energy performance. However, its influence has not been quantified. This paper aims at investigating the impact of space layouts on building energy performance. We use the floor plan of an office building in the Netherlands as reference, and propose eleven space layouts based on the reference. Calculations are performed with the tools Honeybee and Ladybug in Grasshopper, which are developed based on Daysim and EnergyPlus, to simulate lighting, cooling and heating demand of these layouts. In addition, we couple daylight with thermal simulation, by importing the artificial lighting schedule calculated in Daysim to EnergyPlus. The result shows that the heating demand of the worst layout is 12% higher than the best layout, the cooling demand of the worst layout is 10% higher than the best layout, and the lighting demand of the worst layout is 65% higher than the best layout. The total final energy use of the worst layout is 19% higher than the best layout.

The bridge crossing the Cogmanskloof River in the town of Ashton, South Africa, had a history of over-topping due to severe flood events. The poor flood resilience of the bridge was aggravated by the generally hydraulically inefficient openings, the number of substructure supports in the river course, and a high debris load during flooding. The strategically important tourist route had to be closed, while localized flood damage repairs were undertaken, with resultant adverse effects on the local economy. As part of a road safety improvement project between the towns of Ashton and Montagu, improvement of the flooding resistance at the Ashton river bridge was required. This paper documents the functional evaluation of economicand technical-assessments of the flooding risks for the existing retro-fitted bridge. A new tied-arch bridge was the selected structural form of the replacement structure – based on the assessment of the key service life and constructability criteria. The structural form of the Ashton Arch paid careful regard to the scenic location and historic character of the previous multiple arch bridge form.