6 research outputs found
MOESM1 of Rapid in vivo lipid/carbohydrate quantification of single microalgal cell by Raman spectral imaging to reveal salinity-induced starch-to-lipid shift
Additional file 1: Figure S1. The stability test of our Raman setup over 6 hour’s measurement. Figure S2. The raw data without fluorescence background subtraction calculations for the data shown in Fig. 2. Figure S3. The TEM images of microalgal cells under different stress conditions
Assessment of Multiple Sustainability Demands for Wastewater Treatment Alternatives: A Refined Evaluation Scheme and Case Study
Current estimation schemes as decision support tools
for the selection
of wastewater treatment alternatives focus primarily on the treatment
efficiency, effluent quality, and environmental consequences for receiving
water bodies. However, these schemes generally do not quantify the
potential to convert pollutants in wastewater to recoverable resources.
This study proposes a refined evaluation scheme for choices of wastewater
treatment processes that quantifies not only adverse environmental
effects but also bioenergy and nutrient recovery indices. An original
means of data processing was established and clear estimate indicators
were consequently obtained to allow a smooth overall estimation. An
array of wastewater treatment alternatives that meet three effluent
limits were used as case studies to demonstrate how the present scheme
works, simultaneously, to identify optimum choices. It is concluded
in the overall estimation that the lower sustainability of wastewater
treatment contributed by increasingly stringent discharge demands
was offset and mitigated by the resource-recovery scenarios involved,
and the scenario of recovering nutrients via excess-sludge composting
was of more benefit. Thus, before tightening wastewater discharge
requirements, one should bear in mind the situation of multiple sustainability
by setting a goal to achieve not only the greatest reduction in environmental
burden but also the maximum resource-recovery benefits
Decabrominated Diphenyl Ethers (BDE-209) in Chinese and Global Air: Levels, Gas/Particle Partitioning, and Long-Range Transport: Is Long-Range Transport of BDE-209 Really Governed by the Movement of Particles?
In
this paper, we report air concentrations of BDE-209 in both gas- and
particle-phases across China. The annual mean concentrations of BDE-209
were from below detection limit (BDL) to 77.0 pg·m<sup>–3</sup> in the gas-phase and 1.06–728 pg·m<sup>–3</sup> in the particle-phase. Among the nine PBDEs measured, BDE-209 is
the dominant congener in Chinese atmosphere in both gas and particle
phases. We predicted the partitioning behavior of BDE-209 in air using
our newly developed steady state equation, and the results matched
the monitoring data worldwide very well. It was found that the logarithm
of the partition quotient of BDE-209 is a constant, and equal to −1.53
under the global ambient temperature range (from −50 to +50
°C). The gaseous fractions of BDE-209 in air depends on the concentration
of total suspended particle (TSP). The most important conclusion derived
from this study is that, BDE-209, like other semivolatile organic
compounds (SVOCs), cannot be sorbed entirely to atmospheric particles;
and there is a significant amount of gaseous BDE-209 in global atmosphere,
which is subject to long-range atmospheric transport (LRAT). Therefore,
it is not surprising that BDE-209 can enter the Arctic through LRAT
mainly by air transport rather than by particle movement. This is
a significant advancement in understanding the global transport process
and the pathways entering the Arctic for chemicals with low volatility
and high octanol–air partition coefficients, such as BDE-209
MOESM1 of Cell growth and lipid accumulation of a microalgal mutant Scenedesmus sp. Z-4 by combining light/dark cycle with temperature variation
Additional file 1. Figure S1. Effects of light/dark cycles on accumulation of pigment molecules and photosynthetic efficiency under mixotrophic condition. Figure S2. Temperature variation applied in this study. Table S1. The compositions of fatty acids (mass percentage) of microalgal mutant Z-4 at different light–dark cycles under autotrophic condition. Table S2. The compositions of fatty acids (mass percentage) of microalgal mutant Z-4 at different light–dark cycles under mixotrophic condition
Polybrominated Diphenyl Ethers in Air across China: Levels, Compositions, and Gas-Particle Partitioning
Air samples were concurrently collected
using high volume air samplers
for 24 h every week from September 2008 to August 2009 at 15 sites
(11 urban, 1 suburban, and 3 background/rural) across China. Twelve
polybrominated diphenyl ether (PBDE) congeners (BDE-17, -28, -47,
-66, -85, -99, -100, -138, -153, -154, -183, and -209) were measured.
Total PBDE concentrations (∑<sub>12</sub>PBDEs) in air (gas
+ particle phases) were in the range of 11.0–838 pg m<sup>–3</sup> with a mean of 232 ± 72 (mean ± SE) pg m<sup>–3</sup>. The site with the highest concentration was Guangzhou (838 ±
126 pg m<sup>–3</sup>), followed by Beijing (781 ± 107
pg m<sup>–3</sup>). Significant positive correlations were
found between PBDEs levels and urban population (<i>R</i> = 0.69, <i>P</i> < 0.05) and gross industrial output
values (<i>R</i> = 0.87, <i>P</i> < 0.001)
as well. BDE-209 was the dominating congener with the contribution
of 64 ± 23% to ∑<sub>12</sub>PBDEs, followed by BDE-47(8
± 8%) and -99(6 ± 5%) at all urban and suburban sites. At
background/rural sites, however, BDE-47 was the dominating congener,
followed by BDE-99, together accounting for 52 ± 21% of ∑<sub>12</sub>PBDEs, while BDE-209 was only 11 ± 2%. It was found
that PBDEs at the 15 sites showed a primary distribution and fractionation
pattern. This study produced more than 700 pairs of air samples in
gaseous and particulate phases with a wide temperature range of ∼60
°C, providing a good opportunity to investigate gas–particle
partitioning for individual PBDE congeners. The results of gas–particle
partitioning analysis for PBDEs using both subcooled-liquid–vapor
pressure (<i>P</i><sub>L</sub>)-based and octanol–air
partition coefficient (<i>K</i><sub>OA</sub>)-based models
indicated that PBDEs in air at all sampling sites had not reached
equilibrium because the slope values (<i>m</i><sub>O</sub>) in the <i>K</i><sub>OA</sub>-based equation and the opposite
slope values (<i>m</i><sub>P</sub>) in the <i>P</i><sub>L</sub>-based equation at all 15 sampling sites were less than
1. It also found that both <i>m</i><sub>O</sub> and −<i>m</i><sub>P</sub> were significantly and positively correlated
with the annual average temperatures of sampling sites and also significantly
and negatively correlated with the mole masses of PBDE congeners,
indicating a general trend that the higher the temperature at the
sampling site and the lower the mole mass of the PBDE congeners are,
the closer to the equilibrium the congeners approach and vice versa.
To our knowledge, this is the first study to report the correlations
of the slope values for both the <i>K</i><sub>OA</sub>-based
and <i>P</i><sub>L</sub>-based equations with temperatures
at sampling sites and mole masses for individual PBDE congeners
Accelerated Reduction of Chlorinated Nitroaromatic Antibiotic Chloramphenicol by Biocathode
Chlorinated
nitroaromatic antibiotic chloramphenicol (CAP) is a
priority pollutant in wastewaters. A fed-batch bioelectrochemical
system (BES) with biocathode with applied voltage of 0.5 V (served
as extracellular electron donor) and glucose as intracellular electron
donor was applied to reduce CAP to amine product (AMCl2). The biocathode
BES converted 87.1 ± 4.2% of 32 mg/L CAP in 4 h, and the removal
efficiency reached 96.0 ± 0.9% within 24 h. Conversely, the removal
efficiency of CAP in BES with an abiotic cathode was only 73.0 ±
3.2% after 24 h. When the biocathode was disconnected (no electrochemical
reaction but in the presence of microbial activities), the CAP removal
rate was dropped to 62.0% of that with biocathode BES. Acetylation
of one hydroxyl of CAP was noted exclusive in the biocatalyzed process,
while toxic intermediates, hydroxylamino (HOAM), and nitroso (NO),
from CAP reduction were observed only in the abiotic cathode BES.
Electrochemical hydrodechlorination and dehalogenase were responsible
for dechlorination of AMCl2 to AMCl in abiotic and microbial cathode
BES, respectively. The cyclic voltammetry (CV) highlighted higher
peak currents and lower overpotentials for CAP reduction at the biocathode
compared with abiotic cathode. With the biocathode BES, antibacterial
activity of CAP was completely removed and nitro group reduction combined
with dechlorination reaction enhanced detoxication efficiency of CAP.
The CAP cathodic transformation pathway was proposed based on intermediates
analysis. Bacterial community analysis indicated that the dominate
bacteria on the biocathode were belonging to α, β, and
γ-<i>Proteobacteria</i>. The biocathode BES could
serve as a potential treatment process for CAP-containing wastewater