The factors affecting the treatment of oily wastewater with the compound flocculant polyferric sulfate and chitosan were studied by orthogonal experiment.In the experiment, light transmittance, oil content and suspended matter content were selected as test indexes.By means of range analysis of orthogonal experimental results, the order of influence factors such as temperature, PH value, compounding ratio and dosage of flocculant on each index was obtained.After comprehensive analysis, the optimal level combination of each factor was obtained as temperature 50℃, pH 7, inorganic/organic 3:1 and dosage 40mg/L.

Natural gas measurement is divided into volume measurement, quality measurement and energy measurement.At present, China's domestic natural gas trade transfer mainly adopts volume measurement.With the establishment of the national pipeline network company, the interconnection of China's natural gas pipeline network will be accelerated.In order to ensure the fair and just transfer of natural gas trade measurement between different interfaces, natural gas energy measurement will be imperative.This paper analyzes the problems faced by natural gas energy measurement, studies and analyzes the metering interface, measurement error, pricing standard, reform resistance and other aspects, and puts forward specific solutions and suggestions, so as to promote the comprehensive implementation of energy measurement reform of natural gas in China.

The storage battery is an important part of electrical equipment such as UPS, EPS, DC power supply, etc. The running state of the battery will directly affect the overall performance of the electrical system. The timely detection and elimination of potential hidden dangers of the storage battery are of great significance for ensuring the safe and stable operation of production equipment. The valve-regulated sealed lead-acid battery is widely used as a backup power source for electrical systems. This article introduces the operation and use of battery detection tools, conventional battery detection methods, battery maintenance techniques and fault prediction methods.

CdTe quantum dots were synthesized by hydrothermal method, and a method for quantitative analysis of clenbuterol hydrochloride was founded based on the interaction between clenbuterol hydrochloride and CdTe quantum dots. Results shown that clenbuterol hydrochloride had a fluorescence enhancement effect on the fluorescence emission intensity of CdTe quantum dots, and there was a good linear relationship between the increasing of fluorescence intensity (F/F₀) and the concentration of clenbuterol hydrochloride, the linear equations was F/F₀=0.3970C_clenbuterol+1.024, the detection of limit was 0.3402 nmol·L^-1. This method maybe provide an experimental basis for the quantitative analysis of clenbuterol hydrochloride by fluorescence method.

The structures and spectroscopic properties of a series of (C^N)₂Ir(idpt) [C^N= 2-phenylpyridine(1), 2-(5-fluorophenyl)pyridine(2), 2-(4,5,6-trifluorophenyl)pyridine(3), idpt= imidodiphosphinate] complexes were investigated by the density functional methods. We first optimized geometrical structure in ground state of complexes 1-3, at the B3LYP/LanL2DZ levels, and the excited state structures by selected UB3LYP/LanL2DZ functional. The calculated bond lengths of Ir-N(1), Ir-C(1), and Ir-O(1) in the ground state agree well with the corresponding experimental results. At the TD-DFT and CPCM levels, 1-3 give rise to lower energy absorptions at 447(1), 452(2), 424(3) nm and corresponding phosphorescent emissions at 541(1), 499(2), 466(3) nm, respectively. The HOMOs of 1-3 are mainly localized on the metal and bidentate ligands, while the LUMOs are the π* type orbital of bidentate ligands. Therefore, the transition of 1-3 were assigned to the metal-to-ligand and ligand-to-ligand charge transfer (MLCT/LLCT) transition. It is shown that the emitting color are significantly dominated by the phenylpyridine ligand itself and F-substituent group.

The whole design adopts the stepless variable speed AC motor series transmission with step speed regulation. The speed switch of the transmission adopts the shift fork to move the two sets of double gears of the input shaft to change the transmission ratio, so that the main shaft can output 16 step speed within the speed range. The operating mechanism uses double hydraulic cylinder to drive the fork to operate the double gear, so that the input shaft gear can switch the engagement point.At the same time, it improves the overall transmission efficiency and the overall design meets the requirements of automation.

Through analyzing the characteristics of force variation during the rowing process and the working principle of the wind-resistance trainer, the overall scheme of the wind-resistance dragon-boat trainer was designed, and then structural design of the parts. Using software strength of key parts, it is concluded that the related design parameters, meet the design requirements.

In this paper ANSYS Workbench platform is used for static and dynamic finite element analysis of the battery pack enclosure, and the weak position of the box structure is obtained. The box is Optimized by the topography and composite material optimization, The optimum geometric parameters and plane layout of the convex hull on the box cover are obtained by topography of the Optistruct software, final the three-dimensional model of the optimized upper cover is established. The thickness distribution and optimal thickness of each layer in the lower box is obtained by the composite material optimization. After verification, the maximum deformation of the box after optimization is 82% lower than that before optimization, the stiffness is significantly increased, the maximum equivalent stress is reduced by 70%, and the box strength is significantly improved. The first-order natural frequency is 32.5Hz, which can avoid resonance, the box weight is reduced by 67. After optimization the battery pack box can play more effective protective role for the safe operation of the power battery, and the weight reduction effect is significant, the research lays the foundation for further analysis of the actual battery box structure.

For the problem of the nonlinearity,uncertainty and external disturbance of the ball and plate system,in order to make the ball trajectory tracking of the desired dynamic quality,according to the Lyapunov stability theory,firstly combine the state space model of ball and plate system with the low-pass filter,then define the system deviation,select the appropriate Lyapunov function and obtain the virtual function,and finally gradually deduce an inversion controller with low-pass filter.The simulation results show that the improved controller can effectively filter the interference of the system itself and the outside,improve the control precision,and meet the control requirements of the system.

Based on the study of the light hydrocarbon recovery unit, the control scheme was established according to the I/O point table and control requirements, S7-MicroWIN software was selected for programming, and the upper computer monitoring system was developed. The automatic control system of the light hydrocarbon recovery unit based on S7-200 SMART was designed, which not only improved the production level of natural gas, but also recovered valuable liquid hydrocarbons.

On the magnetic field characteristics of generator with single phase short circuit, take a nuclear power half speed turbo-generator as an example, the simulation model of generator single phase short circuit are established by field circuit coupling method. Through the simulation of normal and single phase short circuit of single generator under no load condition, the distribution of the internal magnetic field and the variation characteristics of the air gap flux density before and after the short circuit are obtained. It is pointed out that the magnetic field of the generator is still symmetrical after fault. The air gap flux density is distorted after the fault，Through FFT，the results show that the fundamental component of air gap flux density decreases obviously, while the odd harmonic component increases.

The laboratory of colleges and universities is an important place to complete experimental teaching, conduct scientific research and students to participate in the practice training of innovation and entrepreneurship. Based on the analysis of the current status of the existing laboratories in colleges and universities, an open laboratory management system based on the Internet+ has been developed to cultivate innovation for students Thinking and innovation capabilities provide strong support.

In order to study the variation characteristics of electromagnetic torque of generator under single phase short circuit, taking a nuclear power generator as an example, The simulation model is established by field-circuit coupled method. Through the single phase short circuit simulation of generator with rated load, the variation characteristics of air gap magnetic field and electromagnetic torque before and after the fault are obtained, the harmonic components of electromagnetic torque before and after the fault is analyzed. The results show that the DC component of the electromagnetic torque decreases after the fault, and even harmonic components are generated.

In order to effectively prevent fire accidents in chemical enterprises, 24Model is taken to analyze the risk degree of direct causes and clarify the correlation, based on 16 fire accidents occurred in chemical enterprises from 2015 to 2020. The results show that undetected gas concentration (UA₅) and no effective gas detection procedures in place (UA₆) are dangerous with maximum risk R_UA6=0.611. The formation of flammable gases or gases in unsafe physical conditions reaches the explosion limit are dangerous with maximum risk R_UC7=0.626. Additionally, unsafe action trigger path accounts for 82.98% of the total path at most. Unsafe action with the most associated differences is "unstopped illegal operations”, unsafe condition is "residual explosive substance (UC₁) and material compliance (UC₅)". The main point of accident control is to clarify the cause of unsafe action. The research results can be used as the main basis for the prevention of fire accidents and provide theoretical reference for the implementation of targeted control measures.

The aim of this research is to improve the biomass productivity of chlorella vulgaris FACHB-1072 biomass in the Capillary Action Microalgae Attached Cultivate System.Experiments were performed using the Central Composite Design (CCD) parameters in Response Surface Methodology (RSM). Results showed that the quadratic regression equation of microbial biomass yield, the correlation coefficient of the model was more than 97%. The optimum combination of productivity conditions are: CO₂ flow rate 0.04L/min, Culture Period 124.86 h, light dilution area ratio(R_AD) of 1.33. Under this condition, the productivity of C. vulgaris reached 34.81 g/m²/day.At the same time, the Total Nitrogen (TN )removal rate reached 95.64%, which played a very good sewage treatment effect.

A single-mode microwave digestion-inductively coupled plasma mass spectrometry (ICP-MS) method was established for the simultaneous determination of 19 elements in Jujube. The sample was processed with a full-automatic single-mode microwave digestion-digesting instrument. The ICP-MS analysis conditions were selected and optimized and tested by computer. The results showed that the standard curve concentration of Ag, As, Cr, Ni and other 12 elements ranged from 0 to 50 ng/mL, and the correlation coefficients were all greater than 0.995, showing a good linear relationship. The standard curve concentrations of Al, Ba, Cu, Fe and other 7 elements ranged from 0 to 1000 ng/mL, and the correlation coefficients were all greater than 0.995, showing a good linear relationship. The standard recovery test of each concentration gradient element was conducted at the three levels of 1-fold low-limit, 2-fold low-limit and 10-fold low-limit, and the standard recovery was between 65% and 110%, which met the requirements of quantitative analysis of trace elements. The test method in this study is simple, convenient, reliable, and has high precision and accuracy, which can meet the daily detection requirements of multiple elements in Jujube, and provide technical support for its quality control and safety evaluation.

The antioxidative activity of Astragalus Polysaccharides in different concentration in and out of SH-SY5Y cells was studied, and the antioxidative and free radical scavenging ability of Astragalus polysaccharides was evaluated. DPPH method was used to detect the antioxidant effect in vitro. It was found that with the increasing concentration of Astragalus polysaccharides, the scavenging rate of free radicals also increased. DCF method was used to study the scavenging effect of Astragalus Polysaccharides on intracellular ROS free radicals and the protective effect on cell viability. The results showed that the scavenging effect was consistent with the results of extracellular activity, and the protective effect of 75 mg / mL for 3 h on cell oxidative damage and cell death caused by H2O2 was the best. The results showed that Astragalus Polysaccharide had a good ability of scavenging free radicals.

Protein research is a hot spot at present, and has been involved in biology, medicine, food and other fields, and the development of nanotechnology has greatly promoted the research on protein. Simple, highly sensitive and highly selective detection is the key to the early diagnosis and treatment of major diseases, and it is also the direction with great market potential. However, the synthesis of fluorescent probes for many detection methods is complex and costly, and requires the use of toxic organic reagents. In this study, we detected bovine serum albumin (BSA) using a gold nanocluster (AuNCs@GSH) system with fluorescence quenching by chloramphenicol (CAP) as a probe. BSA could enhance the fluorescence intensity of AUNCs-GSH-CAP system, which was positively correlated with the concentration of BSA within a certain concentration range. This method has good selectivity and anti-interference, and the fluorescence effect is obvious. It has achieved a good linear relationship within 10-160 mol/L, and its detection limit is 0.1 mol/L, which has a good prospect for the rapid detection of proteins.