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Certain heavy metal contaminated site is taken as the example to determine whether the four pollutants, namely As, Cr, Cr (VI) and Ni, exceed the screen levels of soil pollutants for health risk assessment of residential lands specified in Screening Levels for Soil Environmental Risk Assessment of Sites (DB11/T 811-2011) through sampling analysis. In allusion to the main exposure pathway of sensitive population, RBCA model is adopted to assess the health risk of this site, and the results show that the carcinogenic risks of Cr (VI) and As in the three layers of tested sample soils both exceed 10-6 with Cr (VI) and Ni in the first and second layers have larger non-carcinogenic quotient. At last, 10-6 and 1 are regarded as acceptable risk levels, then the RBCA model is used to adversely deduce the pollution remediation target values of the site, and the calculated results are compared with Grade A standards specified in the Assessment Standards for Soil Environmental Quality of Exhibition Lands (Provisional) (HJ350-2007). Then the background values of local soil environment for correction and finally the relatively rational soil pollution remediation target values have been obtained: Cr (VI): 2mg•kg-1, As: 20mg•kg-1, Ni: 50mg•kg-1, Cr: 190 mg•kg-1.

An airdrop model with aerial carrier is carried out to simulate an airdrop test. A coupled CFD/6 DOF is designed to compute the orientation and trajectory of the airdrop model. The results show that the CFD/6 DOF coupled method is appropriate to simulate this problem with a sufficient precision. The airdrop’s motion is strongly coupled with the aerodynamic force after leaving the sliding rail and the trajectory of its CG is mainly in the symmetry of the aerial carrier. The variation of its orientation mainly rolls in X axis direction and it swings as an approximate periodic oscillation which amplitude decreases over time. The maximum angle of orientation in X axis direction is-116°in 5 seconds. The similar variation of the airdrop motion is present in different angle of attack and sideslip of the aerial carrier.

According to the regional sustainable development theory, studied on Wuhu city’s ecological compensation using the ecological compensation framework based on eco-footprint model. The results show that four administrative areas are faced with unsustainable development, the average of the ecological surplus is Wuhu county>urban area>Fanchang county>Nanling county during 2002-2006,the average of the ecological compensation is Wuhu county>Nanling county>Fanchang county>urban area， the ecological compensation of all administrative areas are negative except Fanchang county in 2003, the ecological resources of all administrative areas is not self sufficiency, and should import resource from other area. The research sets the theoretical basis and data support for the distribution of the internal compensate share reasonably in Wuhu city, and rationalizing occupancy of ecological service function.

This study evaluated the feasibility of the mixed material as matrix of eco-toilet and the temporal change of pH value, T-N, T-P, T-K, organic matter and total reduction rate of dry weight in the compost. The mixed material of beanstalk and sawdust with a volume ratio of 1:1 can be used as reaction matrix of on-site composting-type eco-toilet to improve the microbial treatment of human feces. The human feces and urine could be composted to organic fertilizer rich in elements N, P and K. Change of pH in the toilet was divided two phases: changing phase (7.1-8.8) and stable phase (8.4-8.5). T-N, T-P and T-K contents increased with gradual input of feces and urine. Organic matter content decreased from 82.8% to 71.7% and the total reduction rate of dry weight increased gradually from 62.9% to 92.2%. Compost produced in the toilet could be used as organic fertilizer with the optimal concentration ratios for different plants.

Hybrid photovoltaic concepts based on a nanoscale combination of organic and inorganic semiconductors are promising way to enhance the cost efficiency of solar cells through a better use of the solar spectrum, a higher ratio of interface-to-volume, and the flexible processability of polymers. In this work, two types of thin film solar cells have been developed. In both types of solar cells, poly-N-vinylcarbazole (PVK) is used as electron donor, cadmium sulfide (CdS) and titanium dioxide (TiO2) nanocrystals are used as electron acceptors, respectively. Since TiO2 has a wide band gap and can only absorb UV light, in the second type of solar cell, ruthenium dye is used as photo-sensitizer. The preliminary results of photoconductive and photovoltaic characteristics of these two inorganic-organic composites are presented.

After the invention of mesoporous material, the chiral mesoporous materials had been regarded as a hot research issue. Inspired by the chiral phenomenon, in this investigation, we presented several aspect of chiral mesoporous material from its first appearance, especially stated the template that could be used to prepare chiral mesoporous material, including chiral template and achiral template, besides, the different mechanisms and several distinguished scientists’ works were introduced, and some application of these material were introduced such as catalyst, HPLC stationary phases and many other fields.

CdS films were prepared by R.F. magnetron sputtering method. The effects of vapor CdCl2treatment on the properties of CdS films were studied. The vapor CdCl2thermal treatment at different temperature was employed in a CSS device, using CdCl2powder as evaporant. The structural and optical properties of CdS films were investigated by x-ray diffraction (XRD), PL spectra, and transmittance spectra, respectively. The results revealed that the CdS films had a structure of hexagonal wurtzite with a preferential orientation of the (002) plane. A better crystal quality and larger grain size, which are good for the solar cell application, were observed in the CdS samples annealed with CdCl2Subscript text.

In view of the problems of limited energy of the nodes and threat to routing security in wireless sensor networks, Energy-efficient Secure Routing Protocol (ESRP), an energy-efficient secure routing protocol for wireless sensor networks, is proposed. According to the structured topology of hexagonal mesh, hops at different directions are calculated on the optimal route for transmitting data packets in ESRP. With the help of characters of hops, the nodes can rapidly find a route among multiple optimal routes by the policy of the twice probability routing selection. Data breach is prevented by data encryption and data security is realized by one-way hash key chain and symmetric key authentication. Analysis and simulation results show that ESRP has better performance on security and saving energy.

Due to the node failures incurred by intrusion threat, a wireless sensor networks will initiate topology re-generation, which is based on correct availability evaluation of current intrusion-tolerant topology. The paper proposes an availability evaluation model based on semi-Markov process (SMP) to estimate topology availability of the intrusion-tolerant topology concerning the effects from intrusion behaviors. In view of some limitations of node computation ability and storage ability, this model reduces the complexities resulting from modeling the different intrusion threats and is set up on the uniform intruding results to simplify the model design. Using the DTMC model embedded in SMP topology availability is computed and finally we analyze the sensitivity to parameters in the model.

This study aims to investigate the changing of operational parameters and waste reducing rate, as well as the possibility of using produced composts as organic fertilizer in an on-site composting-type eco-toilet filled with mixed materials of beanstalk and sawdust as reaction matrix. During the 23-week period, change of pH was divided into three phases: acid phase (6.63-7.00), alkaline phase (9.00-9.71) and stable phase (8.10-9.00). With continuous input of feces and urine, total nitrogen, total phosphorus and total potassium contents was increased to reach 4.3%, 1.06% and 2.03%, respectively. Organic matter content decreased from 95.6% to 76.2% and the total reduction rate of dry weight increased gradually from 46.93% to 92.29%. The composts could be used as organic fertilizer at suitable concentrations. The suitable concentration for cucumber, cabbage and rape growth was obtained to be at compost ratios of 1:15-1:30, 1:15-1:20 and 1:25-1:40, respectively. Microbial utilization efficiency of human feces and urine could be improved when the mixed material of beanstalk and sawdust was used as reaction matrix in an on-sit composting-type eco-toilet. The mixed materials with beanstalk and sawdust at a volume ratio of 1:1 was found to be efficient to transform human feces and urine into organic fertilizer rich in the elements of N, P and K.

Based on the investigation of two traditional vibratory modes, this paper puts forward a novel vibratory mode in high speed tapping. Vibratory tapping on stainless steel with all kinds of vibratory modes is carefully studied. Experimental results show that the new vibratory mode not only preserves the machining effect of the separable vibratory tapping, but also increases the life of tap. Therefore this study provides a new solution to increase the performance of high speed vibrat- ion tapping.