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Zhang Q.,Hubei Academy of Environmental science | Liu B.,Central Analytical Laboratory
Advanced Materials Research | Year: 2013

The variation of disinfection by-products (DBPs) at several stages of drinking water treatment plants was investigated in two drinking water plants. The results clearly indicate that the low molecular weight total organic carbon (TOC) which has been identified as primary precursor for chlorinated DBPs was difficult to remove by coagulation. Plant A which used conventional coagulation/sedimentation could not decrease the species of trihalomethanes (THMs) and haloacetic acids (HAAs) formation potential. Biological activated carbon (BAC) was applied in Plant B which removed the maximum amount of TOC, while more kinds of microbial products were produced in BAC unit which could be the potential precursors of DBPs. Therefore, the species of DBPs formation potential still increased in the treatment processes of Plant B. Because different components of organic precursors produced different DBPs species, the processes of Plant B could decrease TOC efficiently but the species of THMs and HAAs formation potential. © (2013) Trans Tech Publications, Switzerland.

Zhang Q.,Hubei Academy of Environmental science | Liu B.,Central Analytical Laboratory | Liu W.,Hubei Academy of Environmental science | Zhang B.,Hubei Academy of Environmental science
Chemistry Bulletin / Huaxue Tongbao | Year: 2014

Physical-chemical remediation technology of contaminated soil has become a hot issue by its characteristic of fast speed and high efficiency. Several physical-chemical remediation technologies such as engineering technique, vitrification, thermal remediation, electrokinetic remediation, photodegradation, chemical washing, chemical immobilization, chemical oxidation and combined remediation and their technical features were analyzed to provide reference for the remediation of contaminated soil in China by suitable technology.

Kowalska J.D.,HIV Out Patient Clinic | Kowalska J.D.,Medical University of Warsaw | Czeszko-Paprocka H.,Central Analytical Laboratory | Firlag-Burkackaa E.,HIV Out Patient Clinic | And 2 more authors.
HIV and AIDS Review | Year: 2013

Background: Tuberculosis remains an important healthcare problem in Poland. At the same time tuberculosis is the most common AIDS defining condition diagnosed in HIV-positive persons in Poland. Therefore, we have investigated the prevalence of latent TB infection among healthcare staff of HIV hospital. Material and methods: The interferon gamma release assay (IGRA) was offered to all hospital staff. Participants filled in a self-report questionnaire on demographics, work position, time of employment, occupational and non-occupational contact with TB. In statistical analysis nonparametric tests were used for group comparison. A multivariable logistic regression model was developed including all variables with p < 0.1 in univariable models. Results: Overall 86 (20.9%) of 411 HCW participated in the study. Those with positive IGRA test (12.8%) were older, more likely to undergo TB treatment in the past or having a history of home TB contact. There was no statistical difference between the groups in duration of employment, occupational exposure or its frequency. Factors remaining statistically associated with positive IGRA test was age (OR 1.11, [95% CI: 1.00-1.22]) and home TB contact (OR 36.9, [95% CI: 1.97-688.8]), whereas duration of employment (OR 0.98, [95% CI: 0.89-1.09]) and active TB in the past (OR 0.99, [95% CI: 0.04-25.3]) revealed to be non-significant. Conclusion: The prevalence of latent TB infection among healthcare staff was slightly higher than the one reported in other high income countries. However the risk of acquiring tuberculosis among healthcare workers of HIV hospital was mainly linked to non-occupational exposures. IGRA screening may serve as an important tool in limiting tuberculosis transmission. © 2013 Polish AIDS Research Society. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

Zhang Q.,Hubei Academy of Environmental science | Liu B.,Central Analytical Laboratory | Liu Y.,Fudan University
Environmental Technology (United Kingdom) | Year: 2014

The effect of ozone dose on algae (Microcystic aeruginosa), algal extracellular organic matters (EOM), humic acids (HA) and four model compounds: bovine serum albumin (BSA), starch, deoxyribonucleic acid (DNA) and fish oil as precursors for disinfection by-products (DBPs) production was investigated. Algae showed the highest DBPs formation (71.8 μg mg-1 total organic carbon (TOC)) than other samples. Only BSA showed lower chloroform yield (5.9 μg mg-1 TOC) than haloacetic acids, HAAs (11.2 μg mg -1 TOC). Algae, EOM, starch, DNA, fish oil and HA all showed higher chloroform yields (46.1, 23.8, 8.9, 37.1, 44.0 and 33.7 μg mg-1 TOC, respectively) than HAAs (25.7, 20.2, 6.3, 10.0, 13.1 and 18.4 μg mg -1 TOC, respectively). Pre-ozonation increased DBPs, especially chloroform, formation from algae and DNA significantly. With the increase in ozone doses, DBPs yields of algae and DNA increased 19.0 and 34.5 μg mg -1 TOC, chloroform yields of algae and DNA increased 15.3 and 30.4 μg mg-1 TOC, respectively. However, pre-ozonation decreased DBPs formation from starch, fish oil and HA, and the corresponding decrease amount was 2.4, 26.9 and 9.5 μg mg-1 TOC, respectively. There are no regular change trends of DBPs formation from EOM and BSA with the increase in ozone doses. © 2014 Taylor & Francis.

Zhang Q.,Hubei Academy of Environmental science | Liu B.,Central Analytical Laboratory | Liu Y.,Fudan University | Cai X.,Fudan University | And 2 more authors.
Journal of Water Chemistry and Technology | Year: 2015

The inactivation of virus in raw water was conducted in a continuous flow pilot scale system. Coliphage MS2 was used as model organism for human enteric virus. The effect of disinfection technologies (single or combined process of ozonation and chlorination) and interfering substances (bromide or iodide) on inactivation of virus, and the removal performance of virus in raw water by the pilot scale system (Train A and B) were investigated. The results indicated that bromide or iodide in water was detrimental to ozonation but beneficial to chlorination for virus inactivation. After bromide or iodide was added, the removal of MS2 by ozonation unit was much lower than before (p < 0.01), the removal of MS2 by chlorination unit was significantly higher than before (p < 0.05). Both Train A and B could remove and inactivate MS2 in raw water completely even at high concentration of bromide (675.24 μg/dm3) and iodide (52.33 μg/dm3). The processes of Train A and B can effectively guarantee the virological safety of drinking water. © 2015, Allerton Press, Inc.

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