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Lanthanum molybdate, La2Mo2O9, has been attracted considerable attention owing to its high concentration of intrinsic oxygen vacancies. In this paper, pure and phosphrous-doped La2Mo2O9 (LAMOX) is prepared by means of a modified precipitation method. The properties of the series of compounds have been characterized by thermal analysis (TGA-DTA), X-ray diffraction (XRD), scanning electron microscopy (SEM) and conductivity measured by a.c. impedance spectroscopy (IS). The electrical conductivity of pure La2Mo2O9 prepared by this method reaches a value of 0.15 S/cm at 800 °C, much higher than that of the sol-gel prepared material. P-doped La2Mo2O9 underwent a slightly structural phase transition, and the transition temperature is found to decrease with increasing P content. Electrical conductivity measurements show a slightly increase in the conductivity at low temperature after the tiny doping of P.

Graphene/platinum composite gel was prepared with chloroplatinic acid and graphene oxide (GO) as precursors by in-situ reduction method. Grapheme/platinum composite film as counter electrode was prepared on fluorine-doped tin oxide (FTO) glass by electro-hydrodynamic (EHD) method. Battery was assembled with nanoTiO2film as anode, N3 dye, and ionic liquid electrolyte. It was characterized by Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM) and X-ray Diffraction (XRD). Graphene/platinum composite film include very thin graphene layers, with platinum particles of an average dimension dispersed evenly in graphene layers. This device shows similar photoelectric conversion efficiency compared with platinum electrode under 100 mWcm-2(1 sun) AM1.5 illumination.

A series of experiments have been carried out to study on the efficiencies in solar energy materials and solar cells. Dye-sensitized solar cells (DSSCs) are good examples of where the quality of the nanomaterials and their interfacial properties are important to device performance. In this report, Nanometer TiO2sol for coating film was prepared by cooperating hydrothermal colloidal sol with organic polymer dispersing agent (PVA). Nanocrystalline TiO2porous films were prepared by using electro-hydrodynamic technique (EHD). The results show the films prepared by EHD technique have multilevel hierarchical structure, therefore, better optical scattering properties. Different constituent quasi-solid electrolytes with blood mimetic thixotropy were prepared by cooperating ionic liquid electrolyte with nanometer TiO2colloidal sol synthetized by sol-gel method. The resulting Quasi-Solid-State dye-sensitized solar cells consist of nanoporous TiO2Film and the dye N3, show conversion efficiencies up to 3.7 percent (8. 51 percent with a mask).

The micron-sized Sr2(P2O7):Ce,Tb green phosphors were prepared by being annealed at different temperatures with its precursors synthesized by co-precipitates of (NH4)2HPO4 at ambient temperature. The phase structure, grain size, surface morphology, and luminescent properties of phosphors were investigated by X-ray diffraction, scanning electron microscope, transmission electron microscope, and fluorescence spectrum. The results show that the product of precursor annealed at 1,100 °C is Sr2(P2O7):Ce,Tb, which belongs to orthorhombic phase. The powder is spherical and the size distribution is in micron grade. The sample with the molar ratio of Sr/Tb/Ce of 100.0:0.4:0.6 shows the best fluorescence effect annealed at 1,100 °C for 3 h. The phosphors produce green fluorescence by being excitated with ultraviolet radiation of 254 nm wavelength, and the main emission peak is at 547 nm. The Sr2(P2O7):Ce,Tb phosphors synthesized by co-precipitation method of precursors at ambient temperature is a kind of efficient green-emitting phosphors.

To prepare the amorphous SiO2 optical fiber preform which has lower attenuation, we selected TEOS as raw material, H2O as menstruum, HCl as catalyst, CH3NO as anti-cracking agent, prepared the mandrel material of SiO2 optical fiber preform by sol-gel method. The XRD, SEM, FT-IR and TG were used to study the characteristic of the samples. The results show that the TEOS and H2O can be uniformly mixed with vigorous stirring and water increasing. The hydrolysis rate of TEOS will increase with the increasing HCl volume. The transparency will decrease when the HCl reaches a fixed value. The CH3NO can play a role of anti-cracking agent, it also can affect the transparency if it is more. The optimal capability parameter TEOS: H2O: HCl: CH3NO = 1: 25: 0.5: 0.1. The optimal heat treatment process was determined by TG and FT-IR as follows: the temperature was risen slowly to 170°C and 300 °C for 1h, and then reluxed at 900°C for 2h.

An algorithm based on Credit Assigned Cerebellar Model Articulation Controller(CA-CMAC) fitting Q-learning and improved by a learning parameter of adaptive adjusting balance, is proposed in this paper, which is applied for solving the mobile robot navigation problem in complex environment. Compared to the traditional navigation algorithm, this algorithm avoids local minimum problem, and has a better adaptability and real-time policy-making ability. The local approximation characteristic of the cerebellum model is used to overcome the problem of conventional universal neural network, such as BP, which results in slow convergence speed of neural network or cannot converge. Furthermore, the convergence speed of this algorithm is further accelerated due to introduction of the adaptive adjustment balance parameter. Simulation results indicate that the proposed algorithm improves the algorithm performance, at the same time, whether it is a path, in the simple static obstacles environment or in the complex dynamic obstacles environment, can be successful planned by mobile robot.

A new Knapsack cryptosystem which base on automata theory will be introduced in this paper. In this cryptosystem, by using coresidual relationship, a surjection has been constructed between the input and output in a Knapsack cryptosystem whose coefficients are not ultra-increasing. In block encryption algorithm, with finite automata theory the surjection can be concealed by the previous ciphertext. We offer an example to expound how to construct public and private key, and the process of encryption and decryption. We hope the safety of our cryptosystem can obtain further research.

In order to describe the camera internal geometrical and optical parameters, and the relation between camera and object in three-dimensional space, traditional camera calibration methods usually need to assume lots of priori knowledge, establish precise mathematical model and then decompose and calculate those parameters we need. While artificial neural network has outstanding non-linearity mapping performance, can avoid these process. It only needs to provide some data of input and output for the net, we can imply various parameters into connection weights of the network by certain iterative training. In this paper, a new approach based on Harris corner extraction algorithm and artificial neural network for camera calibration of monocular vision system is presented. Since angles of between the camera and the calibration template are introduced in the calibration process, it only needs a camera to calibration, can achieve the effect similar with the binocular vision system. The experiment results indicated that the method for calibrating is feasible and effective.

To explore an effective way for treating severe complicated distal femoral fractures.Twenty-six patients with complicated distal femoral fracture who all belonged to 33C3.3 type according to AO/ASIF classification, were treated with a lateral condylar buttress plate or self-designed aliform anatomical plate, and operated on with allogeneic bone grafting.All cases were followed up for an average of 14 months (ranging 5-25 months). Twenty-four wounds were primary healing postoperatively, 2 wounds were infected and healed after dressing change. Twenty-four had bone healing after 4-11 months, 2 needed to operate again because of earlier weight-bearing resulting in fixation failure. According to shelbourne and Brueckmann score, the excellent and good rate was 88.46%.The internal fixation for complicated distal femoral fracture by self-designed aliform anatomical plate and lateral condylar buttress plate with a great deal of allograft bone is an effective surgical method. As it has long oval holes and the holes are consecutive, the aliform anatomical plate is more suitable for severe complicated fractures. At the same time, autogenous-ilium transplantation can be substituted by the allograft bone.