Objective To compared the decreasing characteristics of formaldehyde and benzene concentrations in indoor air after decoration. Methods The concentrations of formaldehyde and benzene in indoor air of hotels were determined within one week, one year and more than one year after decoration. Results The concentrations of benzene in indoor air reached the peak(mean: 0.534 mg/m 3) within one week after decoration, and then decreased gradually.The concentrations of formaldehyde were not high within one week after decoration,and then increased gradually, reached the peak (mean: 0.141 mg/m 3) within one year after decoration,then decreased gradually. Conclusion After decoration,the decreasing characteristics of the concentrations of formaldehyde and benzene showed a difference that the concentrations of benzene decreased faster than that of formaldehyde did.

Objective To evaluate the influence of gaseous combustion products of the natural gas (NG), liquefied petroleum gas (LPG) and coal on the indoor air quality. Methods The three kinds of domestic fuels were burned in the designed experimental rooms and the concentrations of SO2, NO2, CO and formaldehyde in the indoor air were determined according to the standard methods at the same time, the emission characteristics of SO2, NO2, CO in these fuels were analyzed also. Results The emission level of CO was the highest in the four combustion products of all three fuels. According to the average daily usage in general families in China, the emission of CO in the coal combustion was much higher than that in combustion of NG and LPG. The unit emission of CO of the coal for house use could reach 30 136 mg/kg, much higher than LPG(8 725 mg/kg)and NG(2 755 mg/kg). The unit emissions of NO2 of LPG combustion (42.69 mg/kg) was higher than the coal and NG (20.01 mg/kg, 11.87 mg/kg), so in the unventilated rooms it could still make the indoor air quality exceed Chinese indoor air quality standard limits. Conclusion Burn of NG or LPG in the kitchen could also cause indoor air pollution.

Nitrogen is an essential nutrient for yeast cells on ethanol fermentation. In order to reveal the promoting mechanisms of organic nitrogen sources on the ethanol fermentation by yeast, Saccharomyces cerevisiae, laser tweezers Raman spectroscopy and single-cell analysis techniques were used to monitored the kinetic of intracellular bio-macromolecules of individual cells during fermentation with urea, yeast extract, ammonium nitrate or ammonium sulfate as the sole nitrogen source. Major results from this work were as follows. (1) Organic nitrogen sources had a promoting effect on the ethanol fermentation, the fermentation with urea and yeast extract reached the maximum concentration of ethanol in 14-18 h. ( 2 ) There were no apparent lag phases for the RNA synthesis of yeast cells cultured with urea and yeast extract. The averaged Raman intensity of yeast cells at peak of 782 cm-1 in the early stage of fermentation was stronger than that of cultured with ammonium nitrate and ammonium sulfate. The maximum was about 1. 9-2. 1 times of the initial intensity for urea or yeast extract, but 1. 2-1. 4 times for ammonium nitrate and ammonium sulfate. (3) The secondary structure of proteins of partial cells cultured with yeast extract was dominated byβ-sheet, while cells cultured with other nitrogen sources were dominated by α-helix absolutely. These results bring us the conclusion that the improving effect of organic nitrogen sources such as urea and yeast extract on ethanol fermentation by Saccharomyces cerevisiae may be due to that the organic nitrogen sources can shorten the lag phase of yeast cells, promote the RNA synthesis, and promote the transcription and expression of related genes.

Efficient mucosal delivery remains a major challenge for the reason of the respiratory tract mucus act as a formidable barrier to nanocarriers by trapping and clearing foreign particulates. The surface property of nanoparticles determines their retention and penetration ability within the respiratory tract mucus. However, the interaction between nanoparticles and mucus, and how these interactions impact distribution has not been extensively investigated. In this study, polymeric nanoparticles loaded with a baicalein-phospholipid complex were modified with two kinds of polymers, mucoadhesive and mucus-penetrative polymer. Systematic investigations on the physicochemical property, mucus penetration, transepithelial transport, and tissue distribution were performed to evaluate the interaction of nanoparticles with the respiratory tract. Both nanoparticles had a similar particle size and good biocompatibility, exhibited a sustained-release profile, but showed a considerable difference in zeta potential. Interestingly, mucus-penetrative nanoparticles exhibited a higher diffusion rate in mucus, deeper penetration across the mucus layer, enhanced cellular uptake, increased drug distribution in airways, and superior local distribution and bioavailability as compared to mucoadhesive nanoparticles. These results indicate the potential of mucus-penetrative nanoparticles in design of a rational delivery system to improve the efficiency of inhaled therapy by promoting mucus penetration and increasing local distribution and bioavailability.