In order to reduce the use of active diluent in UV-curable resin,low viscosity dendritic UV-curable resin was synthesized.Firstly,the 1.0 generation dendritic macromolecule polyamide-amine(G1.0PAMAM)was synthesized using ethylenediamine as the reaction nucleus by means of a two-step iterative reaction of Michael addition and amidation with methyl methacrylate at 25 ℃.Secondly,hydroxy-terminated PAMAM macromolecules were synthesized by reacting hydroxyethyl acrylate with half-generation PAMAM.Finally,dendritic PAMAM resin was synthesized by modifying maleic anhydride(MA)and glycidyl methacrylate(GMA).It was characterized by Fourier transform infrared spectroscopy(FT-IR).The viscosity-temperature properties of PAMAM UV-curable resin were studied.Good thermal stabilities of G0.5PAMAM and G1.5PAMAM UV-curable film were determined,adhesive force were 1,the hardness of pencil were 3H and 4H respectively,the flexibility were 3 mm and 5 mm respectively,and effects of molecular structure on the properties of the coating were discussed in details.
To make full use of the idle roof and provide mid-temperature heat for construction and industrial processes,a compact heat-pipe evacuated tube collector(HPETC)was designed.A thermal resistance theoretical model of the collector was established,and the thermal performance of the collector in Nanjing area was analyzed by variance analysis.Results showed that the collector had a thermal efficiency of 24.56％at 523.15 K.The effect degree of four factors were sorted from small to big:direct radiation,emissivity of selective absorber coating(SAC),pressure of the vacuum tube and inlet temperature.When the pressure in the vacuum tube was less than 0.01 Pa,reducing the emissivity of SAC had a significance in the thermal efficiency.
In order to efficiently react isovaleraldehyde with isobutene and syngas at a lower amount of precious metals,Fe,Co,Ni and Zn-modified Rh/SiO2 catalysts were prepared by conventional impregnation method.The catalyst was characterized by X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR),specific surface area test(BET),H2 programmed temperature reduction(H2-TPR),transmission electron microscopy(TEM)and inductively coupled plasma emission spectroscopy(ICP).The reaction performance of modified Rh/SiO2 catalyst for hydroformylation of isobutene to isovaleraldehyde was studied,and the process conditions such as reaction pressure,reaction temperature,catalyst dosage,reaction time and reaction solvent were optimized.The results showed that with Co as additive,When n(Rh)∶n(Co)was 1∶1,the load(mass fraction)of Rh was 0.1％,the reaction pressure was 5 MPa,the reaction temperature was 100 ℃,the mass ratio of isobutylene to catalyst was 30,the mass concentration of isobutylene was 0.1 g/mL,toluene was the solvent,the stirring rate was 600 r/min and the reaction time was 6 h,The conversion rate of isobutylene was 87.3％and the selectivity of isovaleraldehyde was 97.5％.
A series of hierarchical porous magnesium silicate nanomaterials modified by sodium dodecyl sulfonate(SDS)were applied to adsorb the heavy metal ions Ni2+in industrial wastewater.The concentration of Ni2+in the solution before and after adsorption was determined by inductively coupled plasma emission spectrometer(ICP-AES),and the experimental data were fitted with the kinetic and Langmuir adsorption model.Based on the fitting results of the characterization data and experimental data,the adsorption behavior of the modified materials,the structure-activity relationship between the adsorption efficiency of the modified materials and the specific surface area,pore structure of the adsorbed materials were discussed.Results showed that the equilibrium adsorption capacity of 5-FMS(doped with mass fraction 5％SDS)with large pore size and specific surface area was the largest,which could reach 231.62 mg/g.The adsorption behavior of Ni2+by all materials conformed to the pseudo-second-order kinetic model,which indicated that chemisorptions played a dominant role in the adsorption process.At the same time,the adsorption of Ni2+by all materials conformed to the Langmuir adsorption model well,indicating that the adsorption of Ni2+by all materials was single molecular layer uniform adsorption,and the theoretical adsorption capacity of 5-FMS was the largest,which was 280.40 mg/g.The removal of Ni2+with this series of materials was mainly due to electrostatic adsorption,the surface metal ions(Mg2+)and acid groups exchange with Ni2+in solution.
State of charge(SOC)is an important parameter of power lithium battery management system,and the convergence is relatively poor,and it is easy to fall into the local optimal solution using traditional algorithms to optimize the parameters of the SOC prediction model for lithium battery.In this regard,the improved fruit fly algorithm(IFOA)was used to optimize the parameters of the least squares support vector machines(LSSVM),and the adaptive relaxation term was introduced to improve the prediction accuracy and convergence speed,so as to obtain the global optimal solution.The LSSVM optimized by improved fruit fly algorithm(IFOA)was used to predict the SOC of lithium-phosphate battery,and its operating voltage,operating current and SOC were measured,and the data was used as the test set to establish the SOC prediction model of LSSVM based on the optimization of IFOA on the platform of MATLAB.Results showed that the SOC prediction of lithium-phosphorus battery based on IFOA optimized LSSVM was in very good agreement with the measured results.The simulation results showed that the LSSVM optimized by IFOA had a good agreement with the measured results,the mean absolute error(MAPE)was 1.02％,the generalization ability was strong,and the prediction accuracy was higher than that of the fruit fly algorithm(FOA)-LSSVM and bayesian evidence framework(BEF)-LSSVM models.
