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An in-plane and out-of-plane 2-axis resonator is required for a roll/pitch rate integrating gyroscope (RIG), which is much more challenging in design and fabrication compared with an in-plane 2-axis resonator used in a yaw RIG. In this study, we propose a dynamically balanced out-of-plane resonator to increase the out-of-plane quality factor (Q-factor). A balanced dual-mass structure is designed to reduce the torque applied to the supporting substrate, and thus increase the Q-factor of the out-of-plane mode. Design optimization for frequency matching, reducing mechanical deformation and increasing Q-factor through finite element method (FEM) simulation has been demonstrated. Manufacturing method of the device employing Au-Au thermo-compression bonding has been developed. The fabricated resonator oscillated at around 4380 Hz after remove by using an externally stacked piezoelectric actuator and laser Doppler vibrometer (LDV).

The mechanism of phosphorus removal by iron-contactor process (PRICP) is illustrated from two aspects: metallic corrosion and phosphorus removal by ferric salt. Advances in PRICP are reviewed to shed some light on the research focus in the future for the sake of in-depth study and wide application.

In order to investigate the effect of different carbon resource on enrichment of polyphosphate accumulating organisms (PAO) from sediment samples as well as the effect of PAO on the cycle of phosphorus in lake sediments, sedimentary samples in Lake Taihu were taken and enriched through using four kinds of carbon sources (glucose, cellulose, sodium acetate and propionate) in laboratory-scale sequencing batch reactors (SBRs). The COD/P ratio in the feeding was 15:1. The cycle time was 24 h and consisted of feeding, anaerobic period, aerobic period settle/decant period. The hydraulic retention time was 48 h, and the solids retention time was controlled at approximately 20 days. The dissolved oxygen concentration in aerobic period was maintained at 2-3 mg/L using an pump, where air was supplied at a flow rate of about 1 L/min. The reactor was operated at 25°C with an initial pH of 7.5 ± 0.1. The results showed that the orthophosphate concentration increased at the anaerobic phase in four reactors more or less, and decreased at the aerobic phase, which confirmed that there existed polyphosphate accumulating organisms in sediments of Lake Taihu. While phosphorus release rate using propionate as single carbon resource was the highest, acetate and propionate as substrate were benefit for accumulation of PAO.

This study investigated phosphorus removal in the rivers inputting into Lake Taihu, Jiangsu Province. Ecological community properties of aquatic plants and algae in those rivers were surveyed with focus on diversity and density. The results showed that total phosphorus (TP) concentrations decreased along the runoff in the rivers, and the river with balanced algae community and integrated water plants ecological system had the ability of retention and decontamination of non-point source pollutant-phosphorus. The current velocity and water level also affected self-purification efficiency of the river. It seemed that the rivers inputting into Lake Taihu acted as natural protective screen for pollutants flowing into lake, and natural rivers could be explored for phosphorus removal.

Phenanthrene is a typical polycyclic aromatic hydrocarbon (PAH) found in contaminated water. This study investigated physiological responses of four submerged macrophytes to phenanthrene stress with time, following 40-day exposure to two concentrations of phenanthrene solutions in an outdoor-simulated experiment. A number of parameters including malondialdehyde, soluble carbohydrate and soluble protein contents were monitored. Results showed that the concentrations of phenanthrene in solution decreased obviously with duration of exposure. Subsequently, these four submerged macrophytes could recovered, although several days of phenanthrene exposure resulted in some adverse effects on these plants such as increased malondialdehyde and water soluble protein contents as well as reduced water soluble carbohydrate contents. Changes of these physiological parameters in these submerged macrophytes reflected their continuous tolerance to phenanthrene.