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Light sheet fluorescence microscopy has become a basic tool in biology and medical research with its fast imaging speed, low phototoxicity and high spatiotemporal resolution. Here, we report a novel method to generate multiplane parallel light sheets with a micro structure named isosceles triangular array. The thickness of light sheet in each plane can approach 3.12 μm along with the working distance of 152.20 μm directly generated with the isosceles triangular array. We experimentally recorded the multiplane parallel light sheets illumination, which is consistent with the corresponding simulation by using ray-tracing method. To evaluate the imaging quality, we compared the light field generated with and without projected phase mask onto the spatial light modulator by using polystyrene fluorescent microspheres nanoparticles and transgenic zebrafish. This study provides a potential method for the building of volumetric imaging light sheet fluorescence microscopy with high resolution and low phototoxicity.

Biogas slurry is not suitable for liquid fertilizer due to its high amounts of volatile materials being of complicated composition and peculiar smell. In order to remove volatiles from biogas slurry efficiently, the dynamic headspace and gas chromatography-mass spectrometry were used to clear the composition of volatiles. Nitrogen stripping and superfluous ozone were also used to remove volatiles from biogas slurry. The results showed that there were 21 kinds of volatile compounds in the biogas slurry, including sulfur compounds, organic amines, benzene, halogen generation of hydrocarbons and alkanes, some of which had strong peculiar smell. The volatile compounds in biogas slurry can be removed with the rate of 53.0% by nitrogen stripping and with rate of 81.7% by the oxidization and stripping of the superfluous ozone. On this basis, the removal rate of the volatile compounds reached 99.2% by chloroform and n-hexane extraction, and almost all of odor was eliminated. The contents of some dissolved organic compounds decreased obviously and however main plant nutrients had no significant change in the biogas slurry after being treated.

From May to October in 2010, the content of Nitrogen in Yitong River was detected for six times continuously. And the results showed that the average content of NO 3 −-N in the researching area was not high, but NH 4 +-N and NO 2 −-N were higher relatively. According to their distribution, they all tended to increase from upriver to downriver. And their content changed significantly in different sampling time and space.

Nickel (Ni) plays an important role in the growth of plants, but it is also a kind of heavy metal which can easily enrich in soil and exert toxic effect on plants. To evaluate the Ni stress on the maize growth, a pot experiment was conducted by black soils sampled from the field in the middle of Jilin province. And Ni was equilibrated in the soils to graded levels from 0 to 800mg kg−1 soil. The main results were as follows: The concentration of Ni in maize had a negative correlation with the plant dry weight. The symptom of Ni toxicity was as follows: maize root was short and thin, leaf curled with barred vain and fade blade tip, and it was brown and rotten at the connection of the petiole and roots. In this study, the fitting equation of Y=0.3071+0.0012X+-0.0001CX2 described the extremely significant relationship between the amount of effective Ni in soil (when it was below 30mg/kg) and the dry matter weight of maize. The amount of effective Ni in soil (DTPA extracted) which could provide maize with the best growing state was 6.00mg/kg, the toxicity critical value was 11.48mg/kg, the range of Ni luxury absorption was 6.00 -11.48mg/kg. 11.48- 32.77mg/kg caused maize mild toxicity; 32.77-67.38mg/kg caused moderate toxicity and over 67.38mg/kg leaded to serious toxicity. When maize took place mild toxicity, the content of Ni in maize was 33.40-66.40mg/kg. Moderate toxicity was 66.40-111.40mg/kg. Serious toxicity was over 111.40mg/kg. The equations of Y=-0.0013X+0.3126, Y=-0.0010X+0.3364 could be used to express the relationship between effective Ni in soil, Ni in maize and the dry matter weight of maize when toxicity happened. The highest Ni fixed rate was 23.98% when the soil received 25mg/kg Ni.