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Taking Jilin province rural areas as an example, according to the local climate, environm- ental conditions and basic load case, designed with independent photovoltaic power generation system, the photovoltaic array Angle, photovoltaic panels, battery, inverter and controller and so on has carried on the optimized selection and design. With professional PVSYST photovoltaic software to design the simulation, to meet user demand and system, battery working status, economic and environmental benefits has made the detailed analysis, for the independent photovoltaic solar power systems in Jilin province to promote the study of theoretical basis.

The extended finite element method is applied to modeling growth of arbitrary crack with crack surface tractions. Firstly, the extended finite element method is investigated for the stress intensity factor solution of surface traction problems. Secondly, for different water pressure acting on the crack surfaces and different crack length, the variation of the stress intensity factors is investigated. Finally, the process of hydraulic fracturing is simulated with the method. Numerical simulations illustrate that the method can effectively model the fracture problems with surface tractions.

In this paper the corrosion inhibition of cetyl trimethyl ammonium bromide (CTAB) combined with sodium silicate on the Q235 and 316L steel were investigated. The results showed that CTAB has a higher corrosion inhibition rate but the cost is higher also. In order to lower the cost, the sodium silicate was combined with CTAB to be corrosion inhibitor. The Results showed that once the CTAB was combined with sodium silicate, there would be a synergistic effect between sodium silicate and CTAB. The corrosion inhibition rate could be greater than 80%. Especially when the concentration ratio of CTAB to sodium silicate was 0.02g/L:2.00g/L, the corrosion inhibition rate for the 316L and Q235 could be up to 87.04% and 91.03% respectively.

Based on uniform design, finite element simulation of dieless tube hydroforming and double-screening stepwise regression method, a many-to-many polynomial regression equation set was established, whose independent variables are time t₁ at which axial compression displacement from 0 reaches 25mm and time t₂ at which internal pressure from 0 achieves 65MPa in 60 seconds, while dependent variables are hoop plastic strain s₁₁ and radial plastic strain s₂₂ in the midmost position of hydroformed tube. Analysis of partial correlation coefficient indicates that the effect of t₂ on s₁₁ is a little stronger than t₁ and there is no interaction between t₁ and t₂ on s₁₁, while s₂₂ is influenced by t₂² and t₁t₂². The many-to-many regression model not only quantificationally describes the action of loading factors on plastic strains but also reflects the inherent relevance between plastic strains, which is more useful than several one-to-many regression models to solve problems such as loading characteristic analysis, loading parameters design and optimization, etc.

In this paper, the hydriding of La (Fe, Fe)₁₃ based alloys was realized by the electrolytic method and the effect of electrolytic temperature on the hydriding was investigated. The phase components and surface morphology were analyzed by XRD and SEM. The magnetic properties of samples were characterized using VSM. Results showed that the electrolytic hydriding process was enhanced by increasing the electrolytic temperature. The Curie temperature was increased from 196 K to 325 K. Through Arrot-plot analyses, it was found that the phase transition of samples tends to be a second order phase transition. The magnetic entropy change was reduced from 8.03 J/(kg•K) to 2.03 J/(kg•K) under a maximum external field of 1.5 T.

A new type of tidal unit-vertical shaft tubular turbine is designed with high efficiency, large flow rate and low water head ,which has large power under the 2~3 meters water head. According to the data of the being installed tidal units and principles of tubular turbine’s design, the high efficiency vertical shaft tubular turbine was designed under large discharge and low head, which was suitable for the tidal power station. The design also considered the requirements of turbine’s size and the details of flow through the whole flow passage were attained. The turbine’s property was predicted by the 3-d numerical simulation software on the whole flow passage. Moreover, the influences of vertical shaft’s sizes were analyzed. And the terminal of vertical shaft with or without transverse brace and longitudinal brace were analyzed to get the influence. Considering the hydraulic performance of various methods, the best guide vane opening was chosen. The results show that, the turbine unit has the best performance on efficiency, hydraulic loss, etc. with the guide vane opening 62°, meeting the power station’s design requirements. The results show that the optimal designed flow passage’s efficiency reaches up to 88.4%, the flow rate becomes much larger and the power reaches 174.63kW. Without partial vortex, the flow pattern is smooth through the whole passage also with lower hydraulic loss.

The homogeneous rare-earth catalytic system was used to initiate the polymerization of isoprene, and a novel IR was synthesized with high molecular weight and narrow molecular weight distribution. According to the self-developed rare-earth IR properties, a study on IR and IR/NR blend was made. Microstructure and molecular characteristics of JiHua rare-earth IR were identified by IR spectra, 13C NMR and GPC, and the effect of JiHua rare-earth IR on the vulcanization characteristics and dynamic properties in IR/NR blend was investigated and compared with IR (SKI-3) synthesized with titanium catalyst system and rare-earth isoprene rubber (SKI-5) made in Russia. The results showed that JiHua rare-earth IR to be developed independently was a novel synthetic rubber with excellent comprehensive performance, and it can be used independently and partly substitute natural rubber to make tire. In the IR/NR blend, Not only vulcanization characteristics and the safety in operation for NR was greatly improved, But also dynamic properties of vulcanizates such as dynamic cutting resistance, abrasion resistance, wet-skid resistance and aging resistance were improved to different degrees. These properties reach or surpass the level of the foreign similar products like Russia SKI-3 and Russia SKI-5.

The manganese^II complex [Mn (C₉H₉O₃)₂(H₂O)₂], the Mn^II atom is located on a twofold axis and is coordinated by two ethylvanillinate anions and two water molecule in a distorted octahedral geometry. The ethylvanillinate ligand chelates to the Mn^II atom through its ethyl and hydroxyl O atoms, with greatly differing Mn-O bond distances (2.3988(15)Å and 2.0675(13)Å).Adjacent complex link to each other via hydrogen bonds forming the three-dimensional supramolecular structure.

HEP-BF₄ ionic liquid is prepared by the double decomposition reaction of HEPB and NaBF₄. The ionic liquid at room temperature used in the experiment has a significant absorption determined by UV spectrum within the range of 200-400nm, the maximum absorption wavelength of HEP-BF₄ ionic liquid is 252nm. The standard working curve of HEP-BF₄ ionic liquid is y=0.01529+0.00972X (R=0.99926). The recovery rate of HEP-BF₄ ionic liquid which is between 95.8% and 101%, is measured by standard addition method in water. The quantitative analysis of HEP-BF₄ ionic liquids in water using ultraviolet spectroscopy is simple, accurate and reliable.

By analyzing the transmitionce and heat rate of insulating antireflection films conposed by refractive-index adjustable SiO2 layer and TiO2 layers, the optimum combination of antireflection films of BIPV is obtained. The absorption rate at the ultraviolet part that wavelenght excessive inadequate 400nm of the optimized fils is 99.9%, which are directly designed on the surface of the low iron tempered glass panel of BIPV, and in the wavelength range 400nm-800nm, the visible light transmitionce rate is up to 99.5%, and the heat that wavelenght excessive 800nm is reflected of 20%. For the multilayer heat insulation films are composed with the same kind of material while with different refractive indexes, there is no projecting stress between these films and no constraints during the production process of different films for the possible low cost heat insulating of BIPV.