9 research outputs found
Direct Oil Recovery from Saturated Carbon Nanotube Sponges
Oil
adsorption by porous materials is a major strategy for water purification
and industrial spill cleanup; it is of great interest if the adsorbed
oil can be safely recovered from those porous media. Here, direct
oil recovery from fully saturated bulk carbon nanotube (CNT) sponges
by displacing oil with water in controlled manner is shown. Surfactant-assisted
electrocapillary imbibition is adopted to drive aqueous electrolyte
into the sponge and extrude organic oil out continuously at low potentials
(up to −1.2 V). More than 95 wt % of oil adsorbed within the
sponge can be recovered, via a single electrocapillary process. Recovery
of different oils with a wide range of viscosities is demonstrated,
and the remaining CNT sponge can be reused with similar recovery capacity.
A direct and efficient method is provided to recover oil from CNT
sponges by water imbibition, which has many potential environmental
and energy applications
Two-Stage Chemical Absorption–Biological Reduction System for NO Removal: System Start-up and Optimal Operation Mode
A novel chemical absorption–biological
reduction (CABR)
integrated process, employing FeÂ(II)ÂEDTA as an enhanced absorbent,
is a promising technology for nitrogen oxides removal. In this work,
we developed a new two-stage CABR system applying a mixed cultivation
model of denitrifying bacteria and iron-reducing bacteria, which consists
of a sieve-plate tower and a bioreduction tower to separate the absorption
and reduction processes. The start-up period of the two-stage system
was shortened to 19 days, while that of the one-stage CABR system
was 46 days. In addition, the two-stage CABR system featured a better
oxygen-resistance ability and a higher NO removal loading. In effort
to optimize system operation, we compared different modes of system
operation and found that (1) continuous addition of glucose was better
than the batch-type addition and that (2) the NO removal efficiency
could be maintained at >90% while the FeEDTA concentration was
higher
than 4 mmol/L; however, reducing the initial concentration of ferric
iron complex could inhibit the loss rate of Na<sub>2</sub>EDTA. Furthermore,
the optimized operating mode parameters were 4 mmol/L initial FeÂ(III)ÂEDTA,
0.6 mg/min Na<sub>2</sub>EDTA, and 5 mg/min glucose with a 2 L/min
gas flow rate under a 400 ppm of NO condition, while the NO removal
efficiency was kept >90%; the corresponding operating cost in terms
of glucose was 8.4 g of glucose/g of NO. The purpose of this work
was to provide preliminary data to support future industrial application
for NO<sub><i>x</i></sub> removal, as well as sufficient
technological insights on the process configuration and reactor operation
of the two-stage CABR system
Identification of band fragments in DGGE gels (Fig. 1A).
<p>* Bands are numbered according to <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0116635#pone.0116635.g001" target="_blank">Fig. 1A</a>.</p><p><sup>â—†</sup>Identity represents the sequence identity (%) compared with that in the GenBank database.</p><p>Identification of band fragments in DGGE gels (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0116635#pone.0116635.g001" target="_blank">Fig. 1A</a>).</p
Bacterial diversity index calculated from the DGGE banding patterns (Fig. 1A).
<p>N (negative control, basal diet); P (positive control, diet supplemented with neomycin); L, M, H (diets supplemented with probiotics 0.5×10<sup>9</sup>, 1.0×10<sup>9</sup> and 2.5×10<sup>9</sup> CFU/kg feed, respectively);</p><p>*1/D, the reciprocal of Simpson diversity index.</p><p>Bacterial diversity index calculated from the DGGE banding patterns (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0116635#pone.0116635.g001" target="_blank">Fig. 1A</a>).</p
Dietary <i>Enterococcus faecalis</i> LAB31 Improves Growth Performance, Reduces Diarrhea, and Increases Fecal <i>Lactobacillus</i> Number of Weaned Piglets
<div><p>Lactic acid bacteria (LAB) have been shown to enhance performance of weaned piglets. However, few studies have reported the addition of LAB <i>Enterococcus faecalis</i> as alternatives to growth promoting antibiotics for weaned piglets. This study evaluated the effects of dietary <i>E. faecalis</i> LAB31 on the growth performance, diarrhea incidence, blood parameters, fecal bacterial and <i>Lactobacillus</i> communities in weaned piglets. A total of 360 piglets weaned at 26 ± 2 days of age were randomly allotted to 5 groups (20 pens, with 4 pens for each group) for a trial of 28 days: group N (negative control, without antibiotics or probiotics); group P (Neomycin sulfate, 100 mg/kg feed); groups L, M and H (supplemented with <i>E. faecalis</i> LAB31 0.5×10<sup>9</sup>, 1.0×10<sup>9</sup>, and 2.5×10<sup>9</sup> CFU/kg feed, respectively). Average daily gain and feed conversion efficiency were found to be higher in group H than in group N, and showed significant differences between group H and group P (<i>P<sub>0</sub></i> < 0.05). Furthermore, groups H and P had a lower diarrhea index than the other three groups (<i>P<sub>0</sub></i> < 0.05). Denaturing gradient gel electrophoresis (DGGE) showed that the application of probiotics to the diet changed the bacterial community, with a higher bacterial diversity in group M than in the other four groups. Real-time PCR revealed that the relative number of <i>Lactobacillus</i> increased by addition of probiotics, and was higher in group H than in group N (<i>P<sub>0</sub></i> < 0.05). However, group-specific PCR-DGGE showed no obvious difference among the five groups in <i>Lactobacillus</i> composition and diversity. Therefore, the dietary addition of <i>E. faecalis</i> LAB31 can improve growth performance, reduce diarrhea, and increase the relative number of <i>Lactobacillus</i> in feces of weaned piglets.</p></div
Bacterial community of weaned piglets fed with neomycin or <i>E. faecalis</i>.
<p>(A) DGGE profiles of the V6~V8 regions of the 16S rDNA gene fragments from the samples. The denaturant gradient range is from 42% to 58%. The major difference bands are numbered. Lane S (Standard ladder, which are PCR products generated from different bacterial 16S rDNA genes with primers 968F-GC and 1401R); N (negative control, basal diet); P (positive control, diet supplemented with neomycin); L, M, H (diets supplemented with probiotics 0.5×10<sup>9</sup>, 1.0×10<sup>9</sup> and 2.5×10<sup>9</sup> CFU/kg feed, respectively); (B) UPGMA cluster analysis of Dice similarity indices from DGGE profiles.</p
<i>Lactobacillus</i> diversity index calculated from the DGGE banding patterns (Fig. 2A).
<p>N (negative control, basal diet); P (positive control, diet supplemented with neomycin); L, M, H (diets supplemented with probiotics 0.5×10<sup>9</sup>, 1.0×10<sup>9</sup> and 2.5×10<sup>9</sup> CFU/kg feed, respectively);</p><p>*1/D, the reciprocal of Simpson diversity index.</p><p><i>Lactobacillus</i> diversity index calculated from the DGGE banding patterns (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0116635#pone.0116635.g002" target="_blank">Fig. 2A</a>).</p
<i>Lactobacillus</i> community of weaned piglets fed with neomycin or <i>E. faecalis</i>.
<p>(A) DGGE profiles of V3 region of the 16S rDNA gene fragments with the primes Lac1 and Lac2-GC. The denaturant gradient range is from 41% to 60%. Lanes N (negative control, basal diet); P (positive control, diet supplemented with neomycin); L, M, H (diets supplemented with probiotics 0.5×10<sup>9</sup>, 1.0×10<sup>9</sup> and 2.5×10<sup>9</sup> CFU/kg feed, respectively); (B) UPGMA cluster analysis of Dice similarity indices from DGGE profiles.</p
DataSheet_1_Surface ocean warming near the core of hurricane Sam and its representation in forecast models.docx
On September 30, 2021, a saildrone uncrewed surface vehicle intercepted Hurricane Sam in the northwestern tropical Atlantic and provided continuous observations near the eyewall. Measured surface ocean temperature unexpectedly increased during the first half of the storm. Saildrone current shear and upper-ocean structure from the nearest Argo profiles show an initial trapping of wind momentum by a strong halocline in the upper 30 m, followed by deeper mixing and entrainment of warmer subsurface water into the mixed layer. The ocean initial conditions provided to operational forecast models failed to capture the observed upper-ocean structure. The forecast models failed to simulate the warming and developed a surface cold bias of ~0.5°C by the time peak winds were observed, resulting in a 12-17% underestimation of surface enthalpy flux near the eyewall. Results imply that enhanced upper-ocean observations and, critically, improved assimilation into the hurricane forecast systems, could directly benefit hurricane intensity forecasts.</p