PubMed Health⌕ Search

Biomedical subjects

Yi Qian

Publications and source records attributed to Yi Qian.

51 records · Page 3Linked to original sources
PubMed2003

[Observation and comparison on microstructure of immobilized Aerobacillus fusiformis under wastewater treatment].

Aiming at printing ink wastewater, a strain of bacterium was isolated from activated sludge, and identified as Aerobacillus fusiformis. The Aerobacillus fusiformis was respectively immobilized in calcium alginate gel, polyvinyl alcohol (PVA) and microporous ceramics and their microstructure were observed by scanning electron microscope (SEM). It was found that calcium alginate gel might dissolve in the wastewater, and the activity was restricted as cells wrapped in PVA, so the COD removal ratio was low. The method of immobilized cells using microporous ceramics is simple and COD removal efficiency can be achieved. In addition, the immobilized bacterium could not be separated easily from the ceramics in the wastewater.

Alginates↗
PubMed2003

[Effect of inorganic nitrogen compounds and pH on the growth of duckweed].

The use of duckweed in domestic wastewater treatment was paied increasing attention recently. But inorganic nitrogen compounds and pH of wastewater possibly affect the growth of duckweed. The effect of ammonia, nitrate and pH on the growth of Lemna minor L., a common spiece in China, was assessed with laboratory scale experiments. The experiments used artificial culture with different levels of pH, ammonia and nitrate concentrations. The experimental results indicated that the lowest value of pH Lemna minor can tolerate was between 5-6, and it can grow well in pH from 6 to 9. The growth rate of Lemna minor was inhibited gradually with increasing concentration of ammonia. The toxicity of ammonia was a result of both forms, NH3 and NH4+. Compared to NH4+, the effect of NH3 was much stronger. Nitrate had few inhibitory on the growth of Lemna minor. The increase in ammonia and nitrate concentrations can increase the chloropyll content of Lemna minor. Activity of peroxidase of Lemna minor in ammonia culture was higher than that in nitrate culture because of the toxicity of ammonia.

Ammonia↗
PubMed2003

[Enhance of reproduction of Phanerochaete chrysosporium by adding natural lixiviums in liquid medium].

Great promotion to the reproduction of white rot fungus (Phanerochaete chrysosporium) by adding natural lixiviums such as from wood, maize core and potato in liquid medium was found in this research. Incubated in the liquid medium contained 10 g/L glucose as carbon source with natural lixiviums for three days, the production of mycelium pellet reached more than 80 g/L, which was 5 times of without natural lixiviums. Incubated in the liquid medium contained 5 mg/L glucose as carbon source with natural lixiviums for three days, the production of mycelium pellet can reach 69.5 g/L, while the production of medium without natural lixiviums was very low. When the basic medium contained 1 g/L-20 g/L glucose as carbon source, the production of mycelium pellet in 3 days can only reach 12.5 g/L to 14.5 g/L. The media with potato lixiviums were easily contaminated and the media with maize core lixiviums were easily bulking, while the media with wood lixiviums were not easily contaminated and bulking. Medium with wood lixiviums can produce more pellet than other medium, endure contamination and keep better sedimentation capacity. So, wood lixivium is better additive to the culture of white rot fungi in liquid medium. Addition of the mixture of wood, maize core and potato lixiviums is of advantage to the production of mycelium pellet. The difference of the production in the media with different amount of wood lixiviums showed little in the first 3 days, while it expanded after 3 days. Wood lixiviums stimulate the growth of P. chrysosporium instead of supply organics which fungi need.

Culture Media↗
PubMed2003

[Rural sewage treatment performance of constructed wetlands with different depths].

The treatment performance, for low concentration rural sewage, through constructed wetlands of different depths(60 cm and 40 cm), was comparatively investigated by using pilot-scale apparatus in Lake Dian-chi area, Yunnan province, China. The experiment results showed, under a high hydraulic loading rate of 30 cm/d, that the removal efficiencies of COD, total nitrogen, ammonia-nitrogen and total phosphorus in the constructed wetland of 60 cm depth were 66.4%, 57.7%, 78.7% and 63.2%, respectively, and were 63.8%, 59.1%, 82.1% and 61.3% in the 40 cm depth, respectively. The removal efficiencies of COD and total phosphorus in the constructed wetland of 60 cm depths were higher than those in the 40 cm depth, but the nitrogen removal efficiency in the latter was higher than that in the former. Nitrogen and phosphorus removal mechanisms were studied. The results showed that nitrogen removal through nitrification/denitrification and the phosphorus removal through absorb and sedimentation were their main removal mechanisms. The nitrogen and phosphorus removed by plant harvesting were amounting to 10% and 9% of input TN and TP, respectively, which was also an important removal pathway for nitrogen and phosphorus.

Bacteria↗
PubMed2003

[Performance and its influencing factors of a zeolite biofilter for dilute domestic wastewater treatment].

To reuse dilute domestic wastewater in power plant region as the makeup of recirculating cooling water, a renovate reactor--zeolite media biological aerated filter (ZBAF) was developed. A pilot scale ZBAF of 0.2 m in diameter and 3 m in media height was tested to treat dilute domestic wastewater. The results showed that turbidity, BOD5, CODcr and NH4(+)-N in effluent was 3.2 NTU, 3.2 mg/L, 14.5 mg/L and 0.5 mg/L when the corresponding influent concentration was 59 NTU, 30 mg/L, 81 mg/L and 16 mg/L, respectively, under the conditions of t = 12 degrees C-17 degrees C, HRT = 1.4 h and gas/liquid = 4:1. The effluent quality met the water quality standards of the treated water reused for cooling water makeup. The removal rate of BOD5, COD and turbidity did not change much with the change of HRT and the ratio of gas to liquid, but NH4(+)-N removal rate changed greatly. The parameters along the depth of ZBAF showed that the biofilm phase was abundant in carbon-oxidation/nitrification(C/N) zone and simplex in nitrification (N) zone. Ciliate was plentiful in C/N zone. Biofilm in N zone was mainly consists of nitrifiers. The point that the number of ciliate decreased apparently was the boundary of the two zones.

Ammonia↗
PubMed2003

To enhance the reproduction of Phanerochaete chrysosporium by adding natural lixiviums in liquid medium.

Great promotion to the reproduction of white rot fungus Phanerochaete chrysosporium by adding natural lixiviums such as from wood, maize core and potato in liquid medium was found in this research. Incubated in the liquid medium contained 10 mg/L glucose as carbon source with natural lixiviums for three days, the production of mycelium pellet reaches more than 80 g/L, which is 5 times more than that of without natural lixiviums. Incubated in the liquid medium contained 5 mg/L glucose as carbon source with natural lixiviums for three days, the production of mycelium pellet can reach 69.5 g/L, while the production in the medium without natural lixiviums is very low. When the liquid medium contained 1-20 g/L glucose as carbon source, the production of mycelium pellet in 3 d can only reach 12.5 g/L to 14.5 g/L. The fungus in the medium with potato lixiviums are easily contaminated by other microorganisms and in the medium with maize core lixiviums are easily bulking, while in the medium with wood lixiviums are neither easily contaminated nor bulking. Medium with wood lixiviums can produce more pellet than other medium, endure contamination and keep better sedimentation capacity. So that, wood lixivium is better additive to the culture of white rot fungi in liquid medium. Addition of the mixture of wood, maize core and potato lixiviums is of advantage to the production of mycelium pellet. The difference of the production in the medium with different amount of wood lixiviums showed little in the first 3 d, while it expanded after 3 d. Wood lixiviums stimulate the growth of P. chrysosporium instead of supply organics which fungi need.

Culture Media↗
PubMed2002

[Stability of the two-stage SBR system treating dyeing wastewater during a long-term operation].

The stability of the two-stage SBR system treating dyeing wastewater was investigated during a 120-cycle continuous operation. The system was fed with influent of low dye concentration and high dye concentration. The results showed that the two-stage SBR system was adaptable to the change of influent quality and operation conditions during the long-term operation. It could efficiently remove the pollutants in the wastewater, the average dyestuff and COD removal rates were 81% to 92.5% and 89.4% to 93.1% respectively for low and high influent loading, and could produce continuous good quality effluent. In the two-stage SBR system, the anaerobic sludge had the characteristics of high activity and strong pollutant degradation ability, and the aerobic sludge existed in the form of aggregate structure, which helped stabilize the effluent quality.

Aerobiosis↗
PubMed2002

Kinetic study and modeling on photocatalytic degradation of para-chlorobenzoate at different light intensities.

In order to clarify the dependence of apparent adsorption constant Ks in the Langmuir-Hinshelwood (L-H) model on the incident light intensity, photocatalytic degradation kinetic characteristics were experimentally investigated at different light intensities using para-chlorobenzoate (4-CBA) as a model compound. In all cases 4-CBA initial degradation rates showed dependence on 4-CBA initial concentration, which can be described by the L-H model. However, the adsorption constant Ks and rate constant kr obviously varied with light intensity. To account for the experimental finding, slight modification of the classic kinetic model developed by Turchi and Ollis was tentatively proposed by assuming insufficiency of H2O/OH- available for photo-activated holes' scavenging. Such a kinetic model predicts that both k(r) and Ks(-1) are linearly proportional to the square root of the intensity in a rather large intensity range. The validity of the modified model was proved by fitting it to the experimental data.

Adsorption↗
PubMed2002

[Mechanisms of separating lignin from black liquid by inorganic microfiltration].

The effects of rejection to lignin from black liquid were carried out by inorganic membranes which had pore size 50 nm, 0.2 micron and 0.8 micron, respectively. The results show that MF membranes can effectively separate lignin from black liquid. The flux of 0.2 micron alpha-Al2O3 and ZrO2 membranes were larger than the flux of 50 nm and 0.8 micron membranes. The flux of each membrane drops deeply as the SS concentration increased under the conditions of low SS in black liquid. However, the flux dropping had the linear relationship with SS concentration when it was high. 2 g/L polyethylene glycol 4000 solution can not affect the fluxes of 0.2 micron and 50 nm membranes, effectively, instead of decreasing the flux of 0.8 micron membrane about 60%. 2 g/L polyethylene glycol 20,000 solution can sharply decrease the flux of each membrane. Reason that provoke flux decreasing and change the rejective ability was the cake formation on the surface membrane and the lignin aggregation.

Filtration↗
PubMed2002

[Treatment of a 2,4-dichlorophenol contaminated wastewater in an air-lift inner-loop bioreactor].

An air lift inner-loop bioreactor packed with honeycomb-like ceramic carrier was immobilized with a 2,4-Dichlorophenol-degrading pure culture and was investigated to degrade 2,4-Dichlorophenol and phenol. In fed-batch operation mode, 2,4-DCP biodegradation rate increased with run numbers and followed zero-order kinetics model when it existed alone, but when 2,4-DCP was present in the mixture with phenol, phenol degradation rate had an apparent trend to increase whereas 2,4-DCP removal rate became slower and slower. In continuous operation, 2,4-DCP at the concentration ranged from 6.9 to 102.4 mg/L could be degraded well at the dilution rate of 0.16 h-1 and the average removal percentage was 96.5%. Carbon sources changed from 2,4-DCP to acetate sodium and peptone in the course of operation for 12 days did not cause the bacteria loss the DCP-degrading ability.

Biodegradation, Environmental↗
PubMed2002

[Studies on ceramic dual function membrane bioreactor for wastewater treatment].

A new bioreactor including ceramic dual function membrane, filtration and aeration, was developed and used for wastewater treatment. The turbidity of effluent by the ceramic membrane was comparable to that of 4-24 hours by sedimentation. Aeration and filtration could be switched constantly to the ceramic membrane in the bioreactor and the clogging of ceramic membrane could be well prevented. The wastewater was treated in batch and continues operation modes respectively and the experimental results showed that the COD loading was 1.1 kg/(m3.d) and 1.5 kg/(m3.d) respectively.

Bioreactors↗
PubMed2002

[Association of immune response to hepatitis B vaccine with HLA-DRB1*02, 07, 09 genes in the population of Han nationality in Guangdong Province].

OBJECTIVE: To study the association between immune response to hepatitis B vaccine and HLA-DRB1*02, 07, 09 genes in the population of Han nationality in Guangdong Province. METHODS: A total of 1 400 healthy college students of Han nationality from Guangdong Province were recruited in this study, who received standard courses of vaccination with recombinant hepatitis B virus vaccine at month 0, 1 and 6. Eight weeks after the final vaccination, the serum levels of anti-HBs antibody was examined with enzyme-linked immunosorbent assay (ELISA). Detection of HLA-DRB1*02, 07, 09 alleles were performed with PCR using sequence-specific primers in 118 individuals who failed to produce or produced insufficient antibodies (nonresponders or weak responders), 100 normal responders and 45 strong responders. RESULTS: The frequency of HLA-DRB1*07 in nonresponders or weak responders was significantly higher than that in normal or strong responders (15.25% vs 3.44%, P<0.05), while the frequency of HLA-DRB1*02 was much lower (5.08% vs 17.9%, P<0.05). The frequency of HLA-DRB1*09 showed no obvious difference between the 2 groups (19.49% vs 17.9%, P>0.05). CONCLUSION: Failure or deficiency in the response to HBV vaccine is associated with the HLA-DRB1*07 gene, while HLA-DRB1*02 gene is related to the normal vaccination process or overreaction. Definite relation of HLA-DRB1*09 to the response to HBV vaccine is not found.

Adult↗
PubMed2002

[Pilot study on subsurface wastewater infiltration system applied in rural sewage treatment].

A pilot plant of subsurface wastewater infiltration system (SWIS) filled with red clay was tested to treat rural sewage with hydraulic loading of 2 cm/d. The experiment results showed that average removal rates of COD, NH4(+)-N, total phosphorus, and total nitrogen were 84.7%, 70.0%, 98.0% and 77.7%, with average effluent concentrations of COD, NH4(+)-N, total phosphorus, and total nitrogen being 11.7 mg/L, 4.0 mg/L, 0.04 mg/L and 4.7 mg/L respectively, which met the standard for water reuse issued by the Ministry of Construction of China. Nitrogen removal mechanism analysis revealed that nitrogen in the influent was mainly eliminated through biological removal via nitrification/denitrification processes. In the pilot system, denitrification was well proceeded but nitrification was not satisfactory. How to improve nitrification performance through change of soil environment was the key to enhance nitrogen removal rate. The measurement results of redox potential in the filled soil showed that reductive property of soil was main hindrance to nitrification process.

Filtration↗
PubMedDate not supplied

Clinical cellular cardiomyoplasty: technical considerations.

Three patients, all with a history of coronary heart disease, underwent coronary artery bypass grafting and implantation of autologous satellite cells. Satellite cells were isolated from muscle biopsies of the right vastus lateralis muscle after enzymatic treatment. While the heart was still under hypothermic cardioplegia, 4 mL of cell suspension divided into approximately 40 doses was injected into the ventricular wall of the ischemic area. Less than 5 minutes were required to complete the cell implantation. All patients survived the procedure, without obvious arrhythmia, had an uneventful recovery, and were discharged from the hospital. At 3 to 4 months follow-up examination, increased left ventricular ejection fraction, decreased left ventricular diastolic diameter, as well as improved ventricular wall thickness and perfusion at the satellite cell implantation sites were observed. Our experience indicated the safety and early benefit of cellular cardiomyoplasty using autologous satellite cells.

Aged↗