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Dye-sensitized solar cells (DSSC) are of great scientific significance and application prospect and have attracted wide public concern since they were first reported. The charge recombination in the interface of the DSSC nanocrystalline electrode is thought as a critical issue affecting the DSSC’s performance improvement; however, few systematic studies have been carried out to investigate the effect of the electrolyte additives on the charge recombination suppressing. It is reported that the electrolyte additives can enhance the DSSC short-circuit current. In this work, five typical nitrogen-containing six-element heterocyclic additives used in DSSC were researched theoretically at the B3LYP/6-311G** computational level to elucidate the effects of electrolyte additives on DSSC performance. The five additives were pyridine, pyridazine, pyrimidine, pyrazine and 1,3,5-triazine named as A1–A5, respectively. Their molecular properties, some of which are molecule structures, geometrical configurations, dipole moments, charge distributions, vibrational frequencies and frontier orbitals, were calculated and discussed and their effects on DSSC performance were analyzed theoretically. The results showed an enhanced conjugation effect with the increased number of nitrogen atoms in the conjugated rings of A1–A5 molecules and A1–A5 molecules could bond stably onto the electrode surfaces through the coordination bonding of the N atoms. For the electrolyte additives A1–A5-based DSSC devices, open-circuit voltages and light-to-energy conversion efficiencies increased. This work can be helpful to explain the mechanism of charge recombination suppressing of electrolyte additives for DSSC and offers the potential for future development of high-performance DSSC.

This article is concerned with an electromagnetically semi-permeable elliptical crack embedded in a multiferroic composite medium. The multiferroic composite medium is infinite and subjected to combined magneto-electro-elastic loads applied symmetrically at infinity. The boundary integro-differential equations associated with this nonlinear problem are solved analytically, with the aid of the generalized method of potential theory. The complete and closed-form coupling field is obtained and expressed with two elliptic functions. In addition, the crucial quantities on the crack plane, including the generalized crack surface displacements, the behavior of normal stresses in the crack-tip field and the generalized stress intensity factors, are derived explicitly. Numerical calculation and the finite element analyses for a BaTiO3-CoFe2O4 composite medium are performed to verify the present analytical results and to illustrate the important parameters on the crack plane graphically.

An Unmanned Aerial vehicle (UAV), commonly known as drone, is an aircraft without a human pilot aboard. In recent years, some UAVs are deployed for civil applications, such as policing, firefighting, air pollution monitoring, and aerial search and rescue, etc. Unmanned Aerial vehicle generally include fixed-wing and multi-rotor aircrafts. This research had developed a high endurance quadcopter for search and rescue mission. Target position correction software also was developed in this research. This program uses GPS coordinates embedded in the EXIF information of the aerial photos and more accurately calculates the target’s position. The target’s position error is less than ten meters in 75 meters altitude. Keywords: target position correction software, search and rescue, UAV, quadcopter, and GPS.

Along with the increasing of wind power penetration in the grid, much attention has been paid to the high voltage ride through (HVRT) capability of double fed induction generator (DFIG) based wind parks. To regulate the reactive power dynamically, the distribution static synchronous compensator (D-STATCOM) has been considered to be a valid method. In this paper, the D-STATCOM device is applied to enhance the HVRT capability of DFIG during a symmetrical voltage swell at the grid side. The function, The configuration, operating principle and feed-forward decoupling control strategy is presented, finally the model of power system containing DFIG based wind farms and D-STATCOM is established in the environment of PSCAD/EMTDC, HVRT during symmetrical grid voltage swell is simulated. The validity of the proposed control strategy is verified by the simulation results.

The aim of the present study was to investigate the effects of synuclein-γ (SNCG) downregulation by RNA interference (RNAi) on the clonogenicity and invasiveness of MCF-7 breast cancer cells. This study used four pairs of SNCG-specific siRNAs which were designed and cloned into the pGPU6 plasmid for introduction into an MCF-7 cell line. The SNCG knockdown efficacies of the four siRNAs were compared using the reverse transcription polymerase chain reaction (RT-PCR) and immunocytochemistry. The cells’ clonogenic and invasive phenotypes were examined with clonogenic and Boyden chamber assays. In comparison with the non-specific siRNA and empty vector controls, all four SNCG siRNAs were observed to significantly inhibit SNCG expression at the mRNA and protein levels (F=481.06, P

The unmanned aerial vehicle (UAV) has the advantage of light weight, small size, and better dynamic performance. Conventional UAVs are not well suited for use in confined spaces, such as small passageways or indoor halls, e.t.c. The multi-rotor copters have the vertical take-off and landing (VTOL) ability for indoor flight. The most popular research topics for multi-rotor copters are Quad-copter and Hexa-copter. The objective of this research is to develop a dynamic model for hexa-rotor aerial robot. The dynamic model of the hexa-rotor aerial robot had been studied in this research. The PID control algorithm was used to control the hexa-copter. We used the Matlab software to help us to tune the PID control parameters for quick response and minimizing the fluctuation. From the simulation results, the hexa-copter could make a stable hovering on the target position and return to the stable hovering position and attitude after one motor or one propeller failure.

To explore a new monitoring method for schistosomiasis transmission interrupted areas, so as to evaluate the monitoring results in counties (districts) to improve the quality.Specialized technicians were selected as survey teams to investigate the status of Oncomelania hupensis snails with the random sampling method combined with environmental sampling method every year from 1997 to 2013.From 1997 to 2013, 118 villages of 38 townships of 21 counties were investigated for the snail status, and there were 18 environments with snails in 10 townships of 7 counties. The snail area was 10.91 hm2.There are still small snail areas. Therefore, the snail monitoring should still be strengthened by specialized technicians.