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The unequal leg transmission tower in mountainous areas of 5B-ZBC4 is based to establish the finite element model of three transmission tower and four wire line system. To further study the transmission tower under wind load displacement response, firstly using ANSYS analysis of the dynamic characteristics of the tower-line system. Then, taking the power spectrum of Kaimal wind speed and simulating the curve of wind speed of transmission tower line system in mountainous areas, considering the different elevation and different sizes of wind load, to analysis the wind vibration response for the tower-line coupling system. The results indicates that the tower top displacement means of 1# tower, 2# tower, 3# tower is increasing along with the elevation changes in 0 degrees wind load; The 37 m/s is the critical wind speed of 3# tower of transmission tower line system.

For the interference fit joint of massive flywheel assembly, Studies the reasonable amount of interference and its heating temperature options. Analysis the advantages and disadvantages of various assembly way, reasonable assembly method is proposed, Designed the corresponding assembly tooling , Use the cone positioning and the method of hydraulic push to ensure the higher precision alignment, Provides a reasonable reference for interference fit joint method for the flywheel .

A fatigue life assessment method of steel structures was proposed in this study and applied in a metallurgy crane. Analytical method and experimental analysis were adopted to evaluate the static strength of steel structures, and then dynamic stress test was applied to get the stress history in a whole working cycle, which could determine the interest point and stress spectrum. Finally, rainflow method was applied to approach the stress spectrum, and then the fatigue life was predicted based on Miner rules. The results indicated that this method showed a potential application in practical engineering.

In order to study the residual fatigue life of 500 kv transmission tower under load conditions, a multi-scale finite element model of transmission tower is established. By simulating time course of wind load, using Miner fatigue cumulative damage theory and linear S-N curve, the calculation method of transmission towers fatigue life is established. The research shows that the multi-scale model can better simulate the stress and strain state of the transmission tower, and can predict the remaining service life of the transmission tower .The research has important significance and application value for the safe operation of the transmission lines.

The online identification of low frequency oscillation mode based on measured signal from PMU is the base of damping control. Removing nonlinear trend from the signal effectively can ensure the precision of mode identification. A method named smoothness prior approach (SPA) is proposed to remove the nonlinear trend from measured signal. In order to meet the demand of removing nonlinear trend for identification of low frequency oscillation based on analyzing the basic principle of smoothness prior approach, it determines regularization parameter of smoothness prior approach according to its characteristic of frequency response. It is used to analyze the simulation signals from IEEE-39 bus power system and the measured signals in some power grid, and compared with empirical mode decomposition and digital filter method. The results demonstrate that this proposed method can successfully remove nonlinear trend from the signal and improve the speed of computation, as well as the precision of mode identification, which has a relatively high practical value.

Accuracy three dimensional coordinates of fruits and vegetables are very important to harvesting robots to harvest fruits and vegetables correctly. To decrease the measurement errors of the y coordinates of tomatoes, we analyzed the measurement errors of y coordinate acquired using binocular stereo vision based on three stereo matching methods. These three stereo matching methods were centroid-based, area-based, and combination stereo matching methods. After stereo matching, the three dimensional coordinates of tomatoes could be acquired based on the triangle ranging principle. Tests of 225 pairs of stereo images of three plastic balls used as normal balls acquired at the distances from 300 to 1000 mm showed that the ranges of the measurement errors of y coordinate acquired based on three stereo matching methods changed with the image acquisition distances obviously. Moreover, the measurement errors of y coordinate appeared linear decreasing trends approximately. Therefore, binary linear regression models were set up to reduce the ranges of the measurement errors of y coordinate of three balls. These models were used as correction models of the measurement values of y coordinate and were helpful to reduce the measurement errors of y coordinate. However, there were owe correction and overcorrection conditions when the image acquisition distances were smaller and larger than 750 mm separately. Then, the correction models based on piecewise binary linear regression were used to solve this problem. The ranges of the measurement errors of y coordinate were reduced further. Tests of 225 pairs of stereo images of three tomatoes acquired at the distances from 300 to 1000 mm showed that the ranges of the measurement errors of y coordinate acquired based on three stereo matching methods were separately from [-20.9, -6.6], [-19.9, -3.44], [-19.9, -3.48] mm to [-6.84, -0.06], [-5.84, -0.82], [-5.85, -0.83] mm after the correction using the piecewise binary linear regression models. It proved that the piecewise binary linear regression models were helpful to reduce the measurement errors of y coordinate in three dimensional localization of tomatoes using binocular stereo vision.

ZSM-5/MCM-41 composite zeolites were synthesized by a two-step hydrothermal crystallization procedure using binary templates of cetyltrimethylammonium bromide (CTAB) and tetrapropylammonium hydroxide (TPAOH). The effects of aluminum content on zeolite particle morphology and structure were studied. Powder X-ray diffraction (XRD) results showed that the composite zeolites are of both MCM-41 structure and zeolitic MFI structure. SEM results showed that the morphology of composite zeolites is significantly influenced by the aluminum content.

Cracking of basement structure are common problems in civil building, so it’s most import and difficult to inhibiting cracking of building structures. In this paper, real-time continuous monitoring data of strain and temperature were obtained by embedding sensors in practical engineering, including slab and sidewall of reinforcement concrete, while ambient conditions were monitored to assess their effects. The cracking mechanism of such kind of structure was analyzed based on the investigation and monitoring data. The results show that sidewall is easier to crack than slab for basement structures of civil building, therefore, sidewall cracking of basement structure is the most difficult and key point to inhibit cracking. The measures adopted in this project can effectively reduce crack risk of structure. At the same time, the measured data can provide useful reference to control crack for similar projects and research, and they can also be used to verify the numerical results.

To solve the problem of early-age concrete shrinkage under constraint, 0%, 2%, 3%MgO expansion agent are mixed in the concrete. Results indicate that MgO expansion agent can ensure the expansion strain of the concrete and produce the self-stress under constraint which is up to 1.8Mpa~2.2Mpa.

The understanding of stress relaxation and tensile creep behavior is extremely important in accurate stress analysis and crack prediction of early-age concrete. The free shrinkage deformations of concrete with different strength grade were examined. The early-age tensile elastic modulus of concrete was investigated through temperature-stress testing machine. The tensile creep and shrinkage stress were obtained through the modified restrained ring test. The results indicate that the development of free shrinkage coordinates well with the inner strain of steel ring. Tensile creep decreases as water-binder ratio increases. Creep counteracts tensile stress of concrete by 28%~40% , decreases the possibility of cracking of concrete at early ages.

The solar water heating system is widely applied by all sectors of society because of its safety, health and environmental protection . To better improve the solar water heating system with professional monitoring of high degree of automation , convenience , simple maintenance , the remote control for the solar water heating system based on GSM is put forward , we proceed with the whole scheme design , and the hardware system and software system are also worked out . It proves by practice that the control system has some advantages of safe reliability, low design cost , automatic operation , data collection and analysis for water and electricity .

Basketball sports and training, composed of various essential factors of training, is controlling system 6 which operates on the basis of the existence, the normal circulations and the interchange of in formation inside the system. The whole controlling system of training inform at ion is composed of strategic system, supporting system, an implementing system, with the poach as the core in the implementation of the stategy.The perfecion of strategy making and implementation depends on the in formation feedback of the whole in form at ion controlling system.

In recent years, the detection technology based on machine learning algorithms for distributed denialof-service (DDoS) attacks has made great progress. However, previous methods fail to make full use of contextual information and rely heavily on the probability distribution of the input data. To avoid those pitfalls, the Conditional Random Fields (CRF) model is introduced in this paper for DDoS attacks detection. Firstly, the CRF is trained to build the classification model for DDoS attacks based on three groups of statistical features including conditional entropy, flag ratios and protocol ratios. Then, the trained CRF models are used to identify the attacks with model inference. Experimental results demonstrate that, the proposed approach can accurately distinguish between attacks and normal network traffic, and is more robust to resist disturbance of background traffic than its counterparts.

to solve the difficulties like locating and clamping in the processing of elliptic workpieces and meet the requirements of processing, so as to achieve the final processing purpose. Therefore, the characters of the parts and the best performance of current machining tool are combined, and the mandrel platform with included angle of 45° is prepared on condition that the processing difficulties and requirements are fully understood, and the locating and clamping are achieved by compressing the nuts, then the four-corner chuck is used for alignment and turning, so as to meet the requirements for production.

The effects of phosphates rock (PR) with different particle sizes {D97

In order to study the effect on the structure of pressure-released hole combined support with rockbolt under dynamic loading, utilize RFPA2D-Dynamics on a numerical simulation of dynamic responses of roadway surrounding rock under different depths and different continued time of stress wave and different amplitudes of stress wave. It had gained the general law of the stress redistribution of roadway surrounding rock under static-dynamic coupling loading, and analysed the damage effect of static-dynamic coupling loading to surrounding rock from the perspective of acoustic emission energy release and failure units. Studies show that dynamic disturbance is the main inducing factor on instability of deep roadway supported by pressure-released hole combined support with rockbolt, the waveform of dynamic stress has important influence on broken surrounding rock, with the stress amplitude is the higher and the action time is longer, dynamic disturbance on stability of roadway bring about more significant effect would become.

A fluid dynamics model of electrolyte in mircroflow inspired by hemodynamic model of aortic is proposed and applied in the self-noise analysis of four-electrode microflow-electrochemical accelerometer. Three-dimensional finite element model is established and invested through numerical simulation, the variety of geometrical parameters on different location of electrode and varied time are considered, which can affect the microflow-electrochemical accelerometers self-noise. The result of numerical simulation indicates that, self-noise is related to electrode configuration as well as electrode geometrical parameters. In particular, convection-induced self-noise is correlated to variety of viscosity, and thermohydrodynamic self-noise is correlated to variety of diameter. Such a fluid dynamics model of electrolyte inspired by thermodynamics model can be also used for optimization of the self-noise.

The operational performances of coastal wind farms, located at the east coast of Jiangsu Province of China, are reported in this paper. The result shows that although a rich wind resources predicted in this area, a strong variation of wind resources characteristics are observed between wind farms. Annual averaged wind speeds of five wind farms at hub height range from 4.8 to 6.6 m/s. In addition, the wind shear coefficient shows largely different although they appear to agree with coastal region characteristics. Ru Dong not only has the highest wind shear coefficient but also a largest range of wind shear coefficient variation amplitude. The Capacity Factors of the selected wind farms range from 16% to 27%. Ru Dong shows a lowest Capacity Factor of 16% which may due to the low average wind speed and high wind shear coefficient. On the contrary, Da Feng has a lower Capacity Factor with sensible wind resources indicating either an improved wind turbine technology or an optimized wind farm operational maintenance is needed to increase wind farm efficiency. The result obtained in this paper provides valuable information for future offshore wind farm development in China.

The electronic part of the metal tube rotameter which is based on the magnetic sensors and microcontroller C8051F005 is studied. The flow rate change causes the change of the floats position in the metal tube and leads to rotation of the coupling magnet. Then the change of magnetic angle is detected by the magnetoresistive sensors, and a signal is generated. The signal is processed by the electric circuit and made available for the microcontroller for sampling. Then it will has linearization fitting in the microcontroller and finally has a output. This system could automatically sample the flow signal, calculate the instantaneous flow rate, and display them on the LCD screen.

This paper uses the PHOENICS software to discusses a screen set mode's influence on the indoor mechanical ventilation, then calculated face wind speed, air temperature, air age and PMV. And analyzes the comparison of data, therefore concluded a reasonable way of setting screen in the office building.

Concrete deformation measured under a certain condition in the experiment are very different from those in practical engineering structures, therefore, its necessary to monitor concrete properties in structures. In the paper, by real-time continuous monitoring of reinforcement concrete slab prepared with expansive agent, time-dependent temperature variations and strain variations are obtained and analyzed, and indoor test of the mechanical properties and deformation of field sampling from the slab are presented, so that this completes a transition from the specimen in experiment to the structure in engineering. The result shows that: there was no early-age crack in the four month after casting; the temperature had a certain increase due to heat generation of cement, which can lead to shrinkage deformation in cooling period; the temperature fluctuate with ambient temperature and there are obvious peak temperature rise about 15°C; There was a certain expansion at heating period, which can be considered as compensating shrinkage caused at late age in a certain extent so that minimum strain value is just about-120με which are not beyond the ultimate tensile strain. In addition, the measured experimental data can provide helpful reference for early crack control and durability of concrete structure, and they can also be use to verify and improve the accuracy of the numerical results for slab, which is available in the future for basis to similar projects and research.

Effect of plastic stage curing on long-term properties of high performance concrete (HPC) was studied, thereafter, the mechanism is also analyzed. Results showed that compared to compressive strength, the permeability of surface concrete (especially for silica fume concrete) was more sensitive to plastic stage curing, and deteriorations due to insufficient plastic stage curing cant be eliminated by later longer time of wet curing. Furthermore, the deterioration of pore structure and formation of microcracks were main reasons for insufficient plastic stage curing that affected properties of concrete.

In order to manage and control the settlement along the highway, and meet the needs of the project, it is necessary to study the settlement calculation and prediction methods. Based on the layer-wise summation method, the derivation of the analytic solution of the final settlement can be done through the use of the calculation mode of additional stress and the Integral transform. With an illustrative example, this paper compares the differences of the value of the settlement derived respectively by the specification method and the analytic method. The graphs give an intuitive indication of the performance of the methods, and enable determination of the cubic capacity of settlement of the whole project, laying the foundation for the calculation of the ripped-rock quantity.

We established a typical ripped-rock revetment engineering geoelectric model based the resistivity difference of ripped-rock and its surrounding rock. And we also realized the models’ forward and inversion calculation for different device types of high density resistivity method using finite element method. Results show that the α device could delineate the horizontal scope of the ripped-rock better, and the γ device could reflect the bottom of ripped-rock better than the other three device. In addition, we can also get riprap’s bottom boundary according to the gradient belt of resistivity of the β device. In a real world application, we use the small subdomain filtering technology to enhance the image, better divide the riprap distribution range.

In the research on calculation of interaction of wind and structure, the key to the question is wind field numerical simulation. This paper introduces a practical wind field simulation method of long-span Bridge. The main bridge of Jintang Bridge was analyzed as engineering example, which is a cross-sea cable stayed bridge in Zhoushan of Zhejiang Province , and the linear filter method was applied to calculate along-wind and vertical wind field on main girder, MATLAB program also was adopted to simulate wind field of long-span Bridge. The results show that simulated spectrum is in better agreement with the target spectrum, which verifies validity of the method and correctness of the program.

The rigid-flexible coupled system modeling of parameterization bridge crane is conducted based on Pro/E, Multi-body systems dynamics simulation & Finite element analysis software, simulation of multi-mechanism operation process is performed as well. The results of dynamic simulation were analyzed and summarized, which is essential to complete crane fatigue strength calculation.

Poly (ethylene glycol) modified multi-walled carbon nanotubes were prepared by a green synthesis procedure, including oxidation, acyl chlorination and alcoholysis. All the liquid reagents were recycled by distillation or reduced pressure distillation, and complicated washing or purification was simplified. Fourier transform infrared spectroscopy, scanning electron microscopy and thermogravimetric analysis were used to characterize the samples. The results indicated that PEG was grafted to the functionalized carbon nanotubes (f-CNTs) and the mass percentage of the grafted PEG was about 12%. After sonicatingf-CNTs in ethanol, the dispersibility off-CNTs in ethanol was about 0.46 mg/mL. The stability off-CNTs in ethanol was also tested by left standing a 0.4 mg/mLf-CNT/ethanol solution, no precipitation was found after 10 days.

The role of manufacturing has changed from a producer of products and services to one that integrates the whole industry value chain. In this situation, this paper proposed a new-type networked manufacturing mode which is called outsourcing-driven social manufacturing (od-SM) to solve complex manufacturing problems and perform large-scale collaborative manufacturing. First, the framework of od-SM is proposed. Then, some key enabling technologies such as modeling and community structure of outsourcing-driven social manufacturing network (od-SMN) and generation of outsourcing-driven transient machining system (od-TMS) are talked about in detail. Finally, the conclusions and future work are put forward.

Gallium nitride (GaN) thin films samples were grown by metal-organic chemical vapor deposition (MOCVD) with ammonia and trimethyl-gallium, and the samples were annealed rapidly at different temperature. The scanning electron microscope (SEM) analysis was employed to study the surface morphology and lattice defects of the GaN thin films. The surface morphology of the thin films prepared at different condition was uniform and smoothly. The relationship of the films defects and the annealed temperature were summarized.

Publicly verifiable secret sharing schemes based on Lagrange interpolation utilize public cryptography to encrypt transmitted data and the validity of their shares can be verified by everyone, not only the participants. However, they require O(klog2k) operations during secret reconstruction phase. In order to reduce the computational complexity during the secret reconstruction phase we propose a non-interactive publicly verifiable secret sharing scheme based on the Chinese Remainder Theorem utilizing ElGamal cryptosystem to encrypt data, whonly requires O(k) operations during secret reconstruction phase. Theoretical analysis proves the proposed scheme achieves computation security and is more efficient.

The purpose of this work is to develop a graphical method for describing the work-in- progress (WIP) material flow of a workpiece in order to realize RFID-driven real-time data sampling and support following-up Auto-ID computing. Firstly, various processes in a job-shop floor are formalized graphically by using different types of state-blocks, which depend on RFID detecting spaces and tag detections. And then an event set is deduced from the connecting relations among state blocks and is used for creating the event-driven graphical model in the context of the WIP material flow of a workpiece. To verify the feasibility of the proposed method, a description case is given.

Based on the background of a foundation pit slope of the tertiary strong weathered basalt(TSWB), a quantitative analysis of the slope stability is proposed by combination of the limit equilibrium and the numerical analysis. The analysis also considers the effects of the natural state and soaking state Then, as an example, an ultra-deep foundation pit slope (UFPS) is analyzed under the background of TSWB. The Janbu method is used in the limit equilibrium because it can meet all the equilibrium conditions, including the force and moment equilibrium equation. The Lagrangian difference method which based on shear strength reduction is adopted in numerical analysis. Some meaningful conclusions can be obtained through comparing analysis the calculation results of Janbu method with finite difference method. These conclusions can be given a reference to similar projects.

The riveting quality has an important influence on the performance of the aircraft structure. The amount of interference can be an important indicator of the quality of riveted structure. The relationship between the clearance between rivet and hole and uniformity of interference is researched theoretically and experimentally against the aviation panel riveted structure. First, the riveting deformation stages are divided, and the deformation law is theoretically analyzed. The test scheme is designed and carried out based on the actual situation. Then, the experiment result is monitored and compensated. Finally, the relationship between the clearance between rivet and hole and uniformity of interfere is given out with the slope of interference as the uniform evaluation index.

For automatic lathe tool changing system being widely used in mechanical manufacturing enterprises, this article analyses the life distribution and fault probability of tools. Considering a complete service life circle of the tool, and taking minimum expectation of average cost for producing qualified components as evaluation indicator, the most reasonable tool changing strategy is put forward to reduce production cost in this paper.

This paper designs the pitch controller synthesis to ensure the stability and the controllability in the whole regions as the power grid scheduling instructions. Because of the wind speed measurement and accurate system model are hard to obtain, the range that the actual working point deviating from the balance point is very large, so that the system dynamic performance cannot be described with linear time variable (LTI). This paper utilizes the linear matrix inequalities' techniques (LMI) to design LPV (linear parameter varying) gain-scheduled controllers based on criteria, which provide guarantees of stability performances along the whole reference trajectory. The LPV pitch controller replaces the traditional speed controller to dynamically compensate the pitch angle. According to the errors between the power grid scheduling instructions and measuring the output power, power controller adjusts generator torque to achieve the adjustable power in the whole regions. In view of unmodeled dynamics and wind speed random disturbance, the feed forward linearization. robust pitch regulation using extended state observer (ESO) is proposed to restrain comprehensive disturbances. The proposed controller is seen to be more efficient.

Fatigue damage of airframe often caused by riveting defects, which resulting in failure of aircraft structure in service. Based on the theory of classical fatigue fracture, the effects of Interference-fit gap on capabilities of safe service are examined and a new method of measuring the dimension of Interference-fit gap under the different conditions is introduced by cutting test and fatigue test of typical aluminum alloy 2024-T3 in aero industries. And the admissible value of Interference-fit gap for riveting is given, which offered the technological basis to achieve long fatigue of the aircraft.

In order to supply an effective and reliable tool for the Psychology research in quantity, a multi-parameters psychophysiological feedback analysis system was designed. It can measure several physiological parameters closely related to psychological factors and can realize automatically controlling test gain using a DAC feedback adaptive circuit. Communication protocol is used to increase reliability of data communication and LMS algorithm was used in the system for noise elimination, real-time and data accuracy can be guaranteed. After the debug and verified, multi-parameter system can collect real-time and stable physiological parameters with a higher precision, it provides a feasible monitoring program for psychological assessment.

Under the great trend of social manufacturing, the professional social division of labour in manufacturing industry and the distribution of manufacturing resources force more and more enterprises focus on their core business than ever before and outsource most of the non-core manufacturing activities to other professional organizations. In this condition, this paper proposed a new-type cloud system which is call cloud machining community (CMC) to integrate the distributed MRs and provide on-demand services for service requestors who need them. The framework of CMC together with it working flow is proposed. At last, some key enabling technologies are talked about in detail, such as virtual access of machining resources (MRs) and machining demands (MDs), retrieval and matching between MRs and MDs, generation of machining groups and creditworthiness evaluation mechanism.

By using the Perturbation Theory and solidification coefficient method, based on the interpolation parameters for optimal control feedback matrix, the design of optimal roll control system for a small solid rocket is achieved. The hardware-in-the-loop simulation platform built with DSPACE real-time simulator and high-precision three axis turntable is designed to validate the optimal control law. As for no feedback device of the steering gear, the radios are used to transfer the signals between the devices in the closed loop simulation system. Finally, through the flight-testing, the results confirm a good stability of the roll control system and the high reliability of the hardware-in-the-loop simulation platform.

This paper introduced the method of multidisciplinary design optimization based on genetic algorithm. The basic structure and new auxiliary braking mechanism of permanent magnet retarder was analyzed. The influences of magnetic field parameters, structural design parameters, rotor parameters and permanent magnet temperature parameters on the behaviors performance of the permanent magnet retarder were discussed. The conceptual model of permanent magnet retarder was developed to maximize the brake torque of the permanent magnet retarder. The design variables included the radial width and the axis length of permanent magnet, the number of permanent magnet, the radius of rotor, the thickness of rotor, and the air gas. The constraint conditions included permitting temperature of rotor, saturation magnetic flux density of magnet material, and relation of structural geometry. The results of design optimization variables were obtained by applying genetic algorithm. The multidisciplinary design optimization in this paper is an effective method for the global design optimization of the permanent magnet retarder.

As one kind of indispensable consuming resources, efficient cutting tools management plays an important role in increasing production capacity of machining workshop and ensuring the products quality. In this paper, a RFID-based cutting tools management system (CTMS) is proposed and its implementation framework is established. Furthermore, four key enabling technologies are addressed to investigate the real-time monitoring, dynamic scheduling, inventory alert and life prediction of cutting tools. Finally, a simple example is given to demonstrate the operation procedure of the established CTMS.

For the railway vehicles,flat damage on wheels is a very common defects,the sudden impact and vibration caused by flat damage on wheels endangers the wheels and the rail components a lot.The cause for flat damage on wheels,its physical characteristic, geometric representation,and its precaution are discussed in this paper,and applied to the Simpack multi-body dynamics software, a input form for flat damage on wheel was given.

The choice of supporting plan for a foundation excavation plays a leading role in the optimizing design. For those foundation pits with complex circumstances, a reasonable and optimized supporting construction should be designed to meet the requirements of the surrounding environmental factors. These factors are arranged and rated through a relatively simple analytic hierarchy process (AHP) so as to determine how they affect the design plan of the supporting system. Through ratings and comparisons of relevant factors, a rating method for different design plans is proposed based on AHP analysis. Several supporting plans for a practical excavation engineering in Kunming are analyzed and compared through above method and a reasonable and optimized design plan is selected.

The humid region in south China has abundant rainfall. In order to make effective use of rainfall and save irrigation water, we collected the historical precipitation data of Gaoyou Irrigation District for the past fifty years and used the Geordie Coefficient model of precipitation time evenness index to calculate the precipitation concentration index in different growth stages of rice. The results showed that the precipitation concentration index was low in the early stages of rice; while it gradually increased in the later stages. The precipitation concentration index reached the minimum during the jointing-booting stage and the peak the maturing stage. There were also deceasing trends in precipitation concentration for the early stages. Therefore, it is possible to make better use of rainfall in the early stages of rice growth and save irrigation water. It is necessary to investigate accuracy of rainfall forecasts in future studies.

A sonochemical method has been applied to prepared PbWO4 crystals by using different precursors. The as-prepared samples were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). It was found that the precursor played an important role in the synthesis of PbWO4 crystals. PbWO4 nanostructures with different morphologies, such as flower-like, rod-like, and dendrite-like, have been successfully obtained via a mild sonochemical method corresponding to the precursor PbCO3, Pb(NO3)2, and Pb(Ac)2, respectively.

PbTiO3 crystals with different morphologies, such as flower-like and spherical shape, which was constructed by oriented nanoparticles have been obtained by a simple surfactant-free hydrothermal process assisted by K2CO3 as a mineralizer. Powder X-ray diffraction (XRD) analysis was applied to examine the purity and crystallinity of the as-prepared samples. The morphologies have been characterized by scanning electron microscopy (SEM). The results indicated that the self-assembly structures of PbTiO3 crystals were dependent on the addition amount of K2CO3 and the formation mechanism of the products was briefly discussed.

K0.5Bi0.5TiO3 nanoparticles and quadrate nanoflakes were successfully prepared by a hydrothermal process. The as-synthesized powders were examined by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results suggest that the precursor plays an important role on the formation of K0.5Bi0.5TiO3 crystals and the formation mechanism was also discussed.

The BiFeO3 hollow crystals were successfully prepared at 200oC by a Al3+assisted hydrothermal method. The structures and morphologies of the as-obtained products were characterized by X-ray diffraction (XRD) and field emission scanning electron microscopy (SEM). A morphology evolution from irregular shape to square, hollow, and sphere-like was observed as the Al ions concentration varied from 0% to 1.5%. The possible growth mechanism of the BiFeO3hollow crystals was also discussed.

CdWO4 nanoflakes and nanorods have been successfully prepared through a mild template-free sonochemical method without any surfactants. The as-prepared samples were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). It was found that the ultrasound irradiation played an important role in the formation of CdWO4 crystals. The results showed that CdWO4 nanoflakes were first formed at the early stage, and CdWO4 nanoflakes were transformed into nanorods as the ultrasonic time was prolonged from 0.5h to 1.5h.

The organization of nanostructures across extended length scales is a key challenge in the design of integrated materials with advanced functions. PbZr0.52Ti0.48O3multilayer disks which were constructed by oriented rectangle nanoparticles were easily prepared by a simple surfactant-free hydrothermal process. The as-prepared powders were characterized by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). The results indicated that the as-prepared PZT disks were constructed by self-assembly of rectangle nanoparticles by a perfect manner. The formation mechanism of the products was discussed.