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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.

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.

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.

As an important step of printed formula recognition system, formula extraction locates the formula fields on the layout images of printed documents, which influences the performance of formula recognition to a great extent. However, the errors of automatic formula extraction occur inevitably because of the complexity of formulas themselves and the layouts which the formulas situated. To solve this problem, this paper designed a post-processing method to correct the errors existing in the results of formula extraction algorithm according to relative layout knowledge. First of all, the geometrical features of various layout fields were employed to correct the extraction errors. Then, the syntax rules were used to check the boundary components of different kinds of areas in layouts to identify which field it should belong to. Finally, the formula area was adjusted according to above mentioned information.

As for the pulp-mixing process of small mineral, its flow field configuration principle is to obtain effective cycle in the same operating condition, and allocate strong shearing action according to the needs. This paper takes the coupling of secondary circulating flow pattern as the basis of flow field design to construct the double-impeller function system with the common effects of axial flow impeller and radial flow impeller, thus forming the high-efficient functional mechanism merging strong cycle and strong shearing together. It shows in the result that the effect of double-impeller configuration is strengthened compared to the conventional single-impeller pulp-mixing process: the decrease range of mixing time can reach about 50%; shearing mechanism has effectively blended in the related flow field, and achieved improvement on this basis. It means that the double-impeller configuration has respectively made up the shortage of the cycle performance in the single-impeller radial flow field and the shearing performance in the single-impeller axial flow field, initially formed the mixing mechanism characterized by high-efficient strong cycle mixing and high shearing mixing, and provided practical foundation to develop new and high-efficient modified pulp-mixing equipment.

In this paper, dynamic instability behavior of a linear viscoelastic panel in supersonic flow is investigated. The quasi-steady piston theory of supersonic flow is employed for the aerodynamic pressure. The partial differential governing equation of isotropic flat panel is derived by introducing viscoelastic structural damping based on Kelvins model. The panel governing equation is transformed into a set of ordinary differential equations via the Galerkin approach. First-order state equations are afterwards obtained and solved by means of a standard eigenvalue calculation. The dynamic instability of viscoelstic panels is predicted by the feature of characteristic roots. The phenomena of coupled-mode flutter without structural damping and single-mode flutter with structural damping induced by the supersonic flow are observed for the different dynamic pressure values. Results indicate that structural damping plays an important role for the stability of panels flutter. Flutter threshold keeps decreasing as viscoelastic structural damping is increased.

Using field experiments, the vibration effects of historic tower induced by planed railway line are estimated. The vibrations include the construction vibration and the traffic-induced vibration. The results show that the blasting construction leads to the significant increase in vertical velocity and acceleration. There is no difference between the background vibration of field and foundation of tower. Different types of the sites soil around the tower cause little change. Each measurement time showed an upward trend of vibration level with the increase of frequency. The closer the tower is to the vibration source, the larger the structural vibrations would be. The dominant frequency range for highway-induced vibration is 10-20Hz. For train-induced vibration, the dominant frequency range is more than 40Hz. Surface waves will result in amplification phenomenon of vibration velocity of ancient structures within a certain range.

Optical stimulation of the inner ear, the cochlea, has been proved as a possible alternative to conventional cochlear implant with the hypothetical improvement of dynamic range and frequency resolution. Moreover, the laser has good directionality character and optical signal between adjacent fibers do not readily interfere. Therefore, cochlear implant based on optical stimulation is promising for further exploration and development. The design of an experimental system for optical stimulation of the cochlea is introduced in this paper. For the important part, the selection of NIR laser and the optical signal control methods were discussed. The pulsed laser light was coupled by fiber or fiber array and radiated to the cochlea. For each channel laser pulse, the width modulation was varied from 10us to 1ms, the pulse repetition rate from 5 Hz to 10 KHz, single pulse energy from 0 to 3.6mJ. The application of high precision DAC made the resolution of the pulse energy regulation up to 1uJ/div. The experiment results show that this design and implementation can meet the requirements on further optical stimulation of the cochlea research.