Effects of sepiolite on stabilization remediation of heavy metal-contaminated soil and its ecological evaluation

Stabilization in the remediation of heavy metal contaminated soils has been gaining prominence because of its cost-effectiveness and rapid implementation. In this study, microbial properties such as microbial community and enzyme activities, chemical properties such as soil pH and metal fraction, and heavy metal accumulation in spinach （Spinacia oleracea） were considered in assessing stabilization remediation effectiveness using sepiolite. Results showed that soil pH values increased with rising sepiolite concentration. Sequential extraction results indi- cated that the addition of sepiolite converted significant amounts of exchangeable fraction of Cd and Pb into residual form. Treatments of sepiolite were observed to reduce Cd and Pb translocation from the soil to the roots and shoots of spinach. Concentrations of Cd and Pb exhibited 12.6%-51.0% and 11.5%-46.0% reduction for the roots, respectively, and 0.9%-46.2% and 43.0%- 65.8% reduction for the shoots, respectively, compared with the control group. Increase in fungi and actinomycete counts, as well as in catalase activities, indicated that soil metabolic recovery occurred after sepiolite treatments.

In situ stabilization remediation of cadmium contaminated soils of wastewater irrigation region using sepiolite

The effects of immobilization remediation of Cd-contaminated soils using sepiolite on soil pH, enzyme activities and microbial communities, TCLP-Cd （toxicity characteristic leaching procedure-Cd） concentration, and spinach （Spinacia oleracea） growth and Cd uptake and accumulation were investigated. Results showed that the addition of sepiolite could increase soil pH, while the TCLP-Cd concentration in soil was decreased with increasing sepiolite. The changes of soil enzyme activities and bacteria number indicated that a certain metabolic recovery occurred after the sepiolite treatments, and spinach shoot biomass increased by 58.5%-65.5% in comparison with the control group when the concentration of sepiolite was ~ 10 g/kg. However, the Cd concentrations in the shoots and roots of spinach decreased with an increase in the rate of sepiolite, experiencing 38.4%-59.1% and 12.6%--43.6% reduction, respectively, in contrast to the control. The results indicated that sepiolite has the potential for success on a field scale in reducing Cd entry into the food chain.

Single-shot ultrafast multiplexed coherent diffraction imaging

Classic interferometry was commonly adopted to realize ultrafast phase imaging using pulsed lasers;however, the reference beam required makes the optical structure of the imaging system very complex, and high temporal resolution was reached by sacrificing spatial resolution. This study presents a type of single-shot ultrafast multiplexed coherent diffraction imaging technique to realize ultrafast phase imaging with both high spatial and temporal resolutions using a simple optical setup, and temporal resolution of nanosecond to femtosecond scale can be realized using lasers of different pulse durations. This technique applies a multiplexed algorithm to avoid the data division in space domain or frequency domain and greatly improves the spatial resolution. The advantages of this proposed technique on both the simple optical structure and high image quality were demonstrated by imaging the generation and evaluating the laser-induced damage and accompanying phenomenon of laser filament and shock wave at a spatial resolution better than 6.96 μm and a temporal resolution better than 10 ns.

A Facile Synthesis of Hierarchically Porous TiO2 Microspheres with Carbonaceous Species for Visible-light Photocatalysis

Hierarchically porous anatase Ti02 microspheres composited with carbonaceous species （TCS） have been successfully fabricated by a one-step template-free solvothermal method, combined with subsequent low temperature dried process. In this configuration, the TCS microspheres are constructed by the intercon- nected porous nanosheets, which are further assembled with abundant nanoparticles and carbonaceous species. Such composite microspheres possess a large specific surface area of 337 m2 g-l, uniform mesopores of 3.37 nm and high total pore volumes of 0.275 cm3 g-1. The materials exhibit the enhanced photocatalytic properties and stability for degradation of rhodamine B （RhB） under visible-light irradiation. The enhanced photocatalytic degradation performance may be ascribed to their abundant porous structure, large specific surface area and the unique assist-function of the carbonaceous species.

Spray synthesis of rapid recovery Zno/polyaniline film ammonia sensor at room temperature

As an excellent room temperature sensing material,polyaniline(PANI)needs to be further investigated in the field of high sensitivity and sustainable gas sensors due to its long recovery time and difficulty to complete recovery.The ZnO/PANI film with p-n heterogeneous energy levels have successfully prepared by spraying Zno nanorod synthesized by hydrothermal method on the PANI film rapidly synthesized at the gas-liquid interface.The presence of p-n heterogeneous energy levels enables the ZnO/PANI film to detect 0.1-100 ppm(1 ppm=10^(-6))NH_(3)at room temperature with the response value to 100 ppm NH_(3)doubled(12.96)and the recovery time shortened to 1/5(31.2s).The ability of high response and fast recovery makes the ZnO/PANI filmto be able to detect NH_(3)at room temperature continuously.It provides a new idea for PANI to prepare sustainable room temperature sensor and promotes the development of room temperature sensor in public safety.