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Biological control is an effective method for whitefly management compared to the potential problems caused by chemical control, including environmental pollution and the development of resistance. Combined use of insect parasitoids and entomopathogenic fungi has shown high efficiency in Bemisia tabaci control. Here, we assessed the impacts of an entomopathogenic fungus, Cordyceps javanica, on the parasitism rate of a dominant whitefly parasitoid, Eretmocerus hayati, and for the first time also compared their separate and combined potential in the suppression of B. tabaci under semi-field conditions. Six conidial concentrations of C. javanica (1 &times, 103, 1 &times, 104, 1 &times, 105, 1 &times, 106, 1 &times, 107 and 1 &times, 108 conidia/mL) were used to assess its pathogenicity to the pupae and adults of E. hayati. Results showed that the mortality of E. hayati increased with higher concentrations of C. javanica, but these higher concentrations of fungus had low pathogenicity to both the E. hayati pupae (2.00&ndash, 28.00% mortality) and adults (2.67&ndash, 34.00% mortality) relative to their pathogenicity to B. tabaci nymphs (33.33&ndash, 92.68%). Bioassay results indicated that C. javanica was harmless (LC50 = 3.91 &times, 1010) and slightly harmful (LC50 = 5.56 &times, 109) to the pupae and adults of E. hayati respectively on the basis of IOBC criteria, and that E. hayati could parasitize all nymphal instars of B. tabaci that were pretreated with C. javanica, with its rate of parasitism being highest on second-instar nymphs (62.03%). Interestingly, the parasitoids from second and third-instar B. tabaci nymphs infected with C. javanica had progeny with increased longevity and developmental periods. Moreover, experimental data from 15 day semi-field studies indicate that combined application of C. javanica and E. hayati suppresses B. tabaci with higher efficiency than individual applications of both agents. Therefore, combined applications of C. javanica (1 &times, 108 conidia/mL) and E. hayati is a more effective and compatible biological control strategy for management of B. tabaci than using either of them individually.

Biological control is an effective method for whitefly management compared to the potential problems caused by chemical control, including environmental pollution and the development of resistance. Combined use of insect parasitoids and entomopathogenic fungi has shown high efficiency in Bemisia tabaci control. Here, we assessed the impacts of an entomopathogenic fungus, Cordyceps javanica, on the parasitism rate of a dominant whitefly parasitoid, Eretmocerus hayati, and for the first time also compared their separate and combined potential in the suppression of B. tabaci under semi-field conditions. Six conidial concentrations of C. javanica (1 × 103, 1 × 104, 1 × 105, 1 × 106, 1 × 107 and 1 × 108 conidia/mL) were used to assess its pathogenicity to the pupae and adults of E. hayati. Results showed that the mortality of E. hayati increased with higher concentrations of C. javanica, but these higher concentrations of fungus had low pathogenicity to both the E. hayati pupae (2.00–28.00% mortality) and adults (2.67–34.00% mortality) relative to their pathogenicity to B. tabaci nymphs (33.33–92.68%). Bioassay results indicated that C. javanica was harmless (LC50 = 3.91 × 1010) and slightly harmful (LC50 = 5.56 × 109) to the pupae and adults of E. hayati respectively on the basis of IOBC criteria, and that E. hayati could parasitize all nymphal instars of B. tabaci that were pretreated with C. javanica, with its rate of parasitism being highest on second-instar nymphs (62.03%). Interestingly, the parasitoids from second and third-instar B. tabaci nymphs infected with C. javanica had progeny with increased longevity and developmental periods. Moreover, experimental data from 15 day semi-field studies indicate that combined application of C. javanica and E. hayati suppresses B. tabaci with higher efficiency than individual applications of both agents. Therefore, combined applications of C. javanica (1 × 108 conidia/mL) and E. hayati is a more effective and compatible biological control strategy for management of B. tabaci than using either of them individually.

A dense TiO2 film was fabricated on the titanium surface using the anodization technique. Surface morphology and phase structure of anodic TiO2 film were investigated before and after the hydrothermal exposure at 160 °C for 24 h. The hydrothermal solution was 3.5 wt% NaCl solution and the films were either immersed in NaCl solution or exposed to water vapor during the exposure. It was found that the as-prepared anodic TiO2 film consisted primarily of amorphous oxides and exhibited a relatively smooth surface. After the hydrothermal exposure, lots of rod-like crystals were formed on the solution-immersed film, while aggregated fine nanoparticles emerged on the vapor-exposed one. Thin film X-ray diffraction analysis indicated that the hydrothermal exposure transformed amorphous oxides into crystalline anatase. The corrosion behavior investigation showed that the structural transition of anodic TiO2 film during the exposure reduced the corrosion resistance of anodized titanium greatly.

By incineration treatment became the most important g municipal solid waste disposal method. The bottom ash, which accounting for 20% to 30% of the original municipal solid waste has been a large content source of municipal solid waste in China. The heavy metal will be released to the environment by the eluent produced from the bottom ash. It has a negative influence on bottom ash treatment and reuse. This study analyzed the changing of heavy metals of Cu, Ni and Zn during the elution process by the column simulation experiment. The study revealed the regulation of heavy metals migration under the condition of slow speed elution. These results can help environmental release risk assessment of heavy metal in bottom ash from municipal solid waste incineration plant.

Ten sets of experiments were designed to process non-burnt bricks by adding different proportion of cement as binder and 10% of carbide slag as activator into heavy metal polluted soil. The results showed that: compressive strength at 3d, 7d and 28d of non-burnt bricks compound by T2 were the highest with 10.552MPa, 19.291 MPa and 20.135 MPa respectively, achieving the high quality standard brick. Besides, leaching concentration of heavy metals were lower than that of GB3838-2002 "environmental quality standard for surface water" in V water requirements; heavy metals Pb, Zn, Cu, Cd mostly exist in the organic and residual fraction with 97.88%90.31%97.44% and 98.92% of the total fraction, respectively.

Objectives The aim of the present work is to investigate the effects of cementum–dentine junction (CDJ) and cementum on the stress distribution in the periodontal ligament (PDL) and alveolar bone. Methods Based on the anatomical profiles and the recently reported theories about the tooth attachment mechanism, the finite element (FE) model of a mandibular second premolar along with its detailed supporting structures was developed. The effect of CDJ and cementum was evaluated by comparing the resulting stresses of FE models of the second mandibular premolar with and without CDJ and cementum in tooth supporting structure. Results The stress levels are higher in the structure without CDJ and cementum than that with CDJ and cementum. The function of CDJ and cementum is as a cushion pad decreasing the stress in the PDL and alveolar bone under loading. Conclusions As a major result of this study, it can be concluded that the CDJ and cementum significantly influence the stress distribution within the tooth supporting structure. However, most of the reported FE analysis did not take CDJ and cementum into account, which possibly resulted in overestimated stress values in the PDL and alveolar bone. From a bio-engineering perspective, the results of this study provide guidance for the design of dental implants and the application of orthodontic force system as well.

In this work the mechanical response of tooth supporting structure to the occlusal load was analyzed by means of finite element analysis. The attribution of the cementum-dentine junction (CDJ) and cementum to the stress distribution was investigated. Models of block-shape mandible included a premolar with/without cementum-dentine junction (CDJ) and cementums in the supporting structures were constructed. For each case, a load of 50 N was applied to the crown at a 45-degree angle to the long axis of the tooth. The present finite element analyses indicated that incorporation of CDJ and cementum resulted in decreases in the stress levels. These two tissues are important in absorbing and distributing stress thus they should be considered in analyzing the load transfer characteristics within the tooth supporting structure. In addition, this study proved that it is feasible to simplify the finite element model by employing the modified Young's modulus of PDL to realize the function of CDJ. Moreover, an attempt to correlate the results of the current study with the dental implant designing was made.

Using the optimum blank in sheet metal forming process not only can decrease the material wasting but also avoid possible defects such as local severe thinning, wrinkling and fracture. Since it is practical technology for industrial production, many blank optimization methods have been proposed and their validity was verified by some forming tests of typical or complicated components. However, all the forming tests were carried out at room temperature or under isothermal condition. In present work, a blank optimization method was employed to evaluate its efficiency in deep drawing of rectangular magnesium alloy cups under non-isothermal condition. It is proved by experiment that the employed blank optimization method can predict successfully the optimum initial blank shape for the component with specified shape and dimension.

In the present study, warm hydroforming of cell phone cases with magnesium alloy AZ31 sheets was investigated. Fine-grained magnesium alloy sheets were prepared by cross rolling. And the tensile tests were first conducted in order to determine the proper forming temperature. The results showed that the most suitable temperature range appears to be 150-200°C. At last, the magnesium alloy cell phone cases characterized with the small round radius of all edges were formed successfully at 170°C with the low punch velocity and the maximum pressure not less than 5MPa.

Porous TiO2 layer was fabricated on the titanium surface using an anodic spark oxidation technique for biomedical application. The microstructural and mechanical characterization of TiO2 layer was performed. Results show that the fabricated TiO2 layer exhibited a porous surface and poorly-crystallized structure, and an inner layer containing numerous cavities was observed near the oxide-substrate interface. The mechanical characteristics of TiO2 layer were greatly influenced by its microstructural features. The performed shear test showed that the shear fracture of oxide layer took place primarily within the cavity-containing layer. The performed tensile fatigue loading resulted in multiple cracking to occur in the oxide layer with distinctive inclined cracking driven by slip band in the titanium substrate, and localized spallation of oxide layer was also observed. Despite extensive fatigue damage in the oxide layer, the fatigue life of titanium was not significantly influenced by the present anodization treatment.

Aimed at controlling the nitrogen loss caused by the ammonia gas emission during composting, the mixtures of magnesium hydroxide [Mg(OH)2] and phosphoric acid (H3PO4) were added into composting materials of swine manure and cornstalk. After 26 d composting, ammonical nitrogen and total nitrogen were improved obviously,which were 10.7 g x kg(-1) and 36.9 g x kg(-1) respectively in amended treatment (B), while they were 7.7 g x kg(-1) and 26.8 g x kg(-1) in un-amended trial. By analysis of the total organic carbon, t suggested that amendments accelerated the degradation of organic matter, germination index test showed the maturity of trial B(96%) was better than trial A(82%) in final compost. The scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) analysis confirmed the existence of struvite (MgNH4PO4 x 6H2O). These results indicated that Mg (OH)2 and H3PO4 could accelerate the degradation of organic matter, and reduce the ammonia emission by struvite crystallization reaction.

Warm forming of magnesium alloys has attracted much attention due to the very poor formability of Mg alloys at room temperature. In the present paper, the warm deep drawing of magnesium alloy AZ31 (3 wt.% Al, 1 wt.% Zn) sheets was studied by both the experimental approach and the finite element analysis. The results indicated that the formability of the AZ31 sheets could be improved significantly at elevated temperatures. Sound cups could be formed at 150 degrees C with the highest punch speed of 6 mm/min, while when the forming temperature was increased up to 250 degrees C, sound cups could be drawn with the highest punch speed of 120 mm/min. Finite element analyses were performed to investigate the effects of the process parameters on the drawability of rectangular cups and to predict the formation of the process defects. The reasonable agreement between the numerical simulation results and experimental data validated the accuracy of the finite element analysis. (C) 2008 Published by Elsevier B.V.

The influence of deformation conditions on the formability of magnesium alloy was systematically investigated using the experimental method and finite element analysis. The research activity aimed to gain further insight into the formability of magnesium alloy AZ31 (aluminium 3 wt per cent, zinc 1 wt per cent) and to have first-hand knowledge of the correlations between the material's properties and the processing parameters. In this work, the mechanical properties of magnesium alloy AZ31 sheet were analysed according to the results of tensile tests. A set of experimental equipment with temperature control was employed to perform warm deep drawing of magnesium alloy AZ31 sheets under various forming conditions. The most important process parameters, including the punch speed, the forming temperature, and the geometrical shape of the blank, were taken into account and optimal values were proposed. Finite element analyses were also performed to evaluate the effects of the process parameters on the formability of rectangular cup drawing and to predict the process defects during the process.

Recently, magnesium alloys have been widely applied in automotive and electronic industries as the lightest weight structural and functional materials. Warm forming of magnesium alloys has attracted much attention due to the very poor formability of Mg alloys at room temperature. The formability of magnesium alloy sheet at elevated temperature is significantly affected by the processing parameters. Among them the forming temperature, the punch speed, the geometrical shape of the blank, the blank holder force and the lubrication are probably the most relevant. In this research, the deep drawing of rectangular cups with AZ31 sheets was conducted at elevated temperatures with different process parameters. The finite element analyses were performed to investigate the effects of the process parameters on the formability of rectangular cup drawing and to predict the process defects during the process. The material yield condition was modeled using the isotropic Von Mises criterion. The flow stress data were obtained from tensile tests.