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Algae biocathodes have become one of the most sustainable replacements for abiotic cathodes which were expensive and had toxic chemical oxidant by-products. In this study, a pure culture of Chlorella vulgaris from a photobioreactor was pumped into a photosynthetic microbial desalination cell to treat real landfill leachate (had undergone physical treatment) under varying ‘factor-conditions (FC)’ to embark on a factor-performance relation (FPR) study. This aimed at determining the relationship between operating factors and to depict the most favourable conditions (and range) in order to boost the overall performance of the reactor/cell. Three groups of FC (A, B and C) were adapted, in that, under FC A external resistance was varied, FC B varied pumping rate and FC C varied temperature, light intensity and dissolved oxygen under conditions flow and recirculation mode. Results showed 95% chemical oxygen demand (COD) removal, a maximum power density of 121.57 mWm−2 (anodic volume) and an average desalination rate of 3.93 mg/L/h. The varying results at different FC showed the significant impact of operating conditions on performance. Algae biocathodes also proved to be an essential benefit in boosting the sustainable application of microbial desalination cells (MDCs) in wastewater and landfill pre-treatment as well as the generation of bioenergy.

Based on the test requirement of hydraulic solenoid valve (YDF-16) of a certain aircraft, the test-system of YDF-16 is designed. The test-system consists of a pneumatic unit, a control measure unit and a software unit. It can be used to test the performance parameter of the YDF-16. The test-system is fulfilled the needs of aircraft repair factories and achieves good results in application.

The transmission tower is one of the largest equipment facilities in the transmission and distribution line network. It is mainly used to support the connection of overhead conductors to ensure the safe and stable transmission of power transmission lines. Due to the vast territory of China and the wide distribution of transmission towers, the operating environment faced by transmission towers is also extremely complex. In addition to the pulling force given by the transmission line, rain, snow, dust, salt spray, acid rain and other substances cause erosion and corrosion on the transmission tower. The use of anti-corrosion coatings is an effective way to avoid erosion and corrosion of transmission tower. Therefore, it is very important to prepare an anti-corrosion coating suitable for transmission towers for the safe operation of transmission towers. Graphene is a new type of functional nano-material that attracts attention. Its special layered structure can effectively shield the material, reduce the internal stress of the coating, and improve the adhesion, mechanical properties, anti-corrosion effect and other properties of the coating.

Correlation between endocrine hormones /cytokines and cognitive performance/pathology index of APP/PS1 mice. (PDF 420 kb)

Correlation between endocrine hormone/cytokines and cognitive performance/pathology index of APP/PS1 mice. (PDF 495 kb)

Time delay estimation (TDE) is a hot research topic in wireless location technology. Compressed sensing (CS) theory has been widely applied to image reconstruction and direction of arrival estimation since it was proposed in 2004. The sparse model can be constructed in time domain for estimating the time delay by using the CS theory. The measurement matrix plays a crucial role in the processing of signal reconstruction which is the core problem of CS theory. Therefore the research in the measurement matrix has becomes a hotspot in recent years. The existing measurement matrix is mainly divided into two categories, i.e., random measurement matrix and deterministic measurement matrix. The performance of random measurement matrix has bottlenecks. Firstly, because of the redundant measurement matrix data, the generation and storage of the random number put forward a high requirement for hardware. Secondly the random matrix can only satisfy the restricted isometry property in a statistical sense. The research of the deterministic measurement matrix is of great value under this background. The parity check matrix of low density parity check (LDPC) code has good performance in CS theory. However, the method of randomly selecting non-zero element position has a certain probability to generate a measurement matrix with a short loop structure during generating LDPC code measurement matrix. The robustness of the reconstruction performance decreases with the increase of iteration times. A novel quasi-cyclic CS algorithm based on progressive edge-growth is constructed to estimate the time delay. The purpose of this article is to deal with the need to store a large number of data in existing measurement matrix during time delay, by using the CS theory. The algorithm presented here can achieve TDE in a high precision. First, the theoretical bridge between CS and the maximum likelihood decoding is established. And the design criterion of measurement matrix based on the LDPC code is derived. The sparse measurement matrix with quasi-cyclic structure is constructed by introducing the idea of progressive edge-growth. Finally, the orthogonal matching pursuit algorithm is used to estimate the time delay. Furthermore, the computational complexity of the algorithm and the data storage of the measurement matrix are analyzed theoretically. Simulations show that the correct reconstruction probability of the proposed approach is higher than those of the Gauss random matrix and random LDPC matrix under the same dimension. Compared with the random LDPC matrix, the proposed method can improve performance at the expense of less complexity under the condition of the same data storage.

A b s t r a c t "e Gram-negative Pseudomonas aeruginosa bacterial pathogen is reputed for its resistance to multiple antibiotics, and this property is strongly associated with the development of biofilms. Bacterial biofilms form by aggregation of microorganisms on a solid surface and secretion of an extracellular polysaccharide substances that acts as a physical protection barrier for the encased bacteria. In addition, the P. aeruginosa quorum-sensing system contributes to antibiotic resistance by regulating the expression of several virulence factors, including exotoxin A, elastase, pyoverdin and rhamnolipid. "e organosulfur compound allicin, derived from garlic, has been shown to inhibit both surface-adherence of bacteria and production of virulence factors. In this study, the e!ects of allicin on P. aeruginosa biofilm formation and the production of quorum-sensing controlled virulence factors were investigated. "e results demonstrated that allicin could inhibit early bacterial adhesion, reduce EPS secretion, and down-regulate virulence factors' production. Collectively, these findings suggest the potential of allicin as a therapeutic agent for controlling P. aeruginosa biofilm. K e y w o r d s: Pseudomonas aeruginosa , allicin; antibiotic resistance, biofilm, virulence factor

From the perspective of balancing urban and rural development, this article researches the factors influencing the consumption level of rural residents in China. I select the relevant data concerning per capita net income of rural households and annual per capita consumer spending of rural residents for living in the period 1985-2008, establish the regression model of per capita net income of rural households and per capita consumer spending of rural residents for living, and conduct regression analysis and error correction model test using the measurement software. The analysis results show that there is not only long-term equilibrium relationship between rural residents' current consumption and rural residents' current income, between rural residents' consumption in lag period 1 and rural residents' income in lag period 1, but also short-term equilibrium relationship; current income is the main reason for determining the current consumption). Corresponding proposals are put forward to promote the level of rural consumption in China as follows: propel agricultural modernization; actively develop specialized cooperative organizations of rural residents; improve rural land transfer mechanism; promote the level of public services in rural areas; accelerate the transfer of rural surplus labor.

A hybrid model for size add-on is built in slashing process. In the hybrid model, mechanism model is master model, intelligent model is auxiliary model, and the output relationship is determined by integrated rule in output model. When either sensors break down or operation conditions are abnormal, auxiliary model will estimate output by the external input variables. This hybrid model uses adequately field data so that predictive performance of hybrid model is multi-sided guaranteed.

In a passive target tracking system, the position and velocity of a target can be estimated based on time difference of arrival (TDOA) and frequency difference of arrival (FDOA) received by different stations. But TDOA and FDOA equations are nonlinear, which make the target tracking become a nonlinear estimation problem. To solve the nonlinear estimation problem, the most extensive research algorithms are those of extended Kalman filter (EKF), particle filter (PF), unscented Kalman filter (UKF), quadrature Kalman filter (QKF), and cubature Kalman filter (CKF). But the existing algorithms all come up with shortcoming in some way. EKF only retains the first order of the nonlinear function by Taylor series expansion, which will bring large error. PF has to face the degeneracy phenomenon and the problem of large computational complexity. The standard UKF is easy to become divergence in a high dimensional state estimation. QKF is sensitive to the dimension of state, and the calculation is of exponential growth with the growth of dimension. Although CKF can effectively improve the shortcomings, the discarded error is proportional to the state dimension, which may be large in high dimensional state. In view of the above problems, this paper presents an orthogonal cubature Kalman filter (OCKF) algorithm. This algorithm reduces the sampling error by introducing special orthogonal matrix to change the method of cubature sampling based on CKF. It eliminates the dimension impact on the sampling error. In the absence of additional computation, it effectively improves the tracking precision. Simulation results show that, based on the TDOA and FDOA, compared with the EKF and CKF algorithms, OCKF algorithm can improve the tracking performance significantly.

The impacts of varying layout geometries on the channel temperature of multi-finger AlGaN/GaN HEMTs are investigated by three-dimensional (3-D) thermal simulations. Micro-Raman thermography is selected to obtain a detailed and accurate temperature distribution of the sample for the verification of the 3-D thermal models. Thermal boundary resistance (TBR) plays an important role in the temperature distribution and is taken into account in the thermal model in order to improve the accuracy of the simulated results. The influence from the number of fingers, finger width and gate pitch on the gate temperature are systematically analysed using 3-D thermal simulations with validated model parameters. Furthermore, a robust method that could efficiently reduce the thermal crosstalk of multi-finger AlGaN/GaN HEMTs is proposed to optimize the thermal design of the device.

The effects of varying layout geometries and various thermal boundary resistances (TBRs) on the thermal resistance of multi-finger AlGaN/GaN HEMTs are thoroughly investigated using a combination of a two-dimensional electro-thermal model coupled with the three-dimensional thermal model. Temperature measurement using micro-Raman thermography is performed to verify and enhance the accuracy of the thermal model. Simulation results indicate that thermal resistance weakly depends on the layout design because of the high thermal conductivity of SiC. Meanwhile, the analysis reveals that optimizing the TBR of the device could efficiently reduce the thermal resistance since TBR takes a significant proportion of the total thermal resistance.

A heat engine model of a sing particle confined in a one-dimensional harmonic trap is established. The model, as a quantum-mechanical analog of the Carnot engine, does work to outside when both the width of the potential and the quantum state change very slowly. On the assumption that the width of the potential moves at a very slow speed and the heat leakage is included, we derive the general expressions for several performance parameters, such as work, power output, efficiency, etc. We find the optimally operating regions and the optimal values of performance parameters of the heat engine cycle.

Reliability assessment of SiN MIM capacitors in GaN MMIC is performed by constant voltage stress test. Two kinds of failure modes, critical charge density at which the dielectric breaks down and mean time prior to failure are investigated. The trap energy level in SiN dielectric is obtained by temperature dependent current characteristics. The degradation mechanism of SiN MIM capacitor is analyzed. The research shows that new donor-like traps are generated at dominant position during the stress. And the trap energy level becomes deeper after stress. The increased trap accelerates the scattering of the carrier, which leads to the decrease of leakage current in the end. The investigation on the failure mechanism of SiN MIM capacitor provides a reference for reinforcing the dielectric capacitors.

The influence of gate voltage on electron transport in the graphene field-effect transistor under strong laser field is studied by using the finite-difference time-domain method. The perfect tunneling in graphene can be strongly suppressed by the strong laser field induced optical stark effect. This suppression depends not only on the laser field but also on the width and the height of the gate voltage. The electron transport through a non-square barrier is investigated. We find that a barrier with a small incline has little effect on the electron transport, but if the barrier has a large incline, the tunneling probability changes remarkably.