The influence of titanium doping on the electrochromic properties of WO3 thin films is studied. The systematics of different properties such as the structural phase change, the color-bleach kinetics, ...coloration efficiency, reversibility, stability, ion insertion/extraction capacity and change of W+ 6 states to W+ 5 states are observed to depend on doping concentration. The X-ray diffraction results reveal an amorphous phase at lower Ti concentration (2 and 6 at.%) and mixed WO3-TiO2 (monoclinic epsilon WO3 and rutile TiO2) phases at higher Ti concentration (10 at.%). The fibrous-reticulated morphology wanes and surface roughness increases as doping concentration increases. At higher Ti concentration (10 at.%), the film becomes completely granular and rough without fibrous-bridge-like network. The cycle stability, charge storage capacity and reversibility of the films are improved upon doping; however, coloration efficiency is decreases as Ti concentration increases. These results are discussed in terms of the effects of doping induced compositional inhomogeneity and disorder structure on the film properties.
Results from the PHENIX experiment at RHIC on direct photon production in p+p, d+Au, and Au+Au collisions at =200 GeV are presented. In p+p collisions, direct photon production at high pT behaves as ...expected from perturbative QCD calculations. The p+p measurement serves as a baseline for direct photon production in Au+Au collisions. In d+Au collisions, no effects of cold nuclear matter are found within the large uncertainty of the measurement. In Au+Au collisions, the production of high pT direct photons scales as expected for particle production in hard scatterings. This supports jet quenching models, which attribute the suppression of high pT hadrons to the energy loss of fast partons in the medium produced in the collision. Low pT direct photons, measured via e+e- pairs with small invariant mass, are possibly related to the production of thermal direct photons.
Aims: The involvement of the aniline‐degradative plasmid pNB2 in degradation of 3‐chloroaniline (3‐CA) was investigated.
Methods and Results: Plate matings of a Pseudomonas putida strain containing ...pNB2 with a mixed bacterial culture derived from activated sludge was carried out. After inoculation of the mating mixtures into batch cultures containing 3‐CA, degradation of the compound was observed. A total of five different transconjugant strains could be isolated from one of the batch cultures and two of them were able to degrade 3‐CA. These two isolates were identified as Comamonas testosteroni by partial 16S rDNA sequencing.
Conclusions: It can be assumed that pNB2 carries a part of the genes involved in the catabolism of 3‐CA, but that completion of the pathway must be provided by chromosomal genes in the host strain.
Significance and Impact of the Study: pNB2 is a candidate plasmid which can be used in plasmid‐mediated bioaugmentation of wastewater bacteria involved in degradation of chlorinated anilines.
Titanium dioxide, or titania, is perhaps the most well-known and widely studied photocatalytic material, with myriad applications, due to a high degree of tunability achievable through the ...incorporation of dopants and control of phase composition and particle size. Many of the applications of titanium dioxide require particular forms, such as gels, coatings, or thin films, making the development of hybrid solution processable nanoparticles increasingly attractive. Here we report a simple solvothermal route to highly dispersible anatase phase titanium dioxide hybrid nanoparticles from amorphous titania. Solvothermal treatment of the amorphous titania in trifluoroacetic acid leads to the formation of anatase phase nanoparticles with a high degree of size control and near complete surface functionalisation. This renders the particles highly dispersible in simple organic solvents such as acetone. Dopant ions may be readily incorporated into the amorphous precursor by co-precipitation, with no adverse effect on subsequent crystallisation and surface modification.
Solvothermal treatment of amorphous titania in trifluoroacetic acid modifies the surface and crystallises the anatase phase, yielding dispersible hybrid nanocrystals.
Aims: The applicability of plasmid pNB2 for bioaugmentation of bacteria in model wastewater treatment reactors receiving 3‐chloroaniline (3‐CA) was investigated.
Methods and Results: A setup of ...three biofilm reactors was studied, all initially inoculated with bacteria from activated sludge. Reactor PB received a Pseudomonas putida pNB2 donor strain not able to degrade 3‐CA. Positive control reactor P received a 3‐CA degrading Comamonas testosteroni pNB2‐transconjugant. The negative control reactor N remained unchanged. Reactor P showed 3‐CA degradation from the beginning of the experiment whereas in reactor PB, degradation started after an initial lag period. No degradation was observed in reactor N. PCR analysis showed that the P. putida donor abundance dropped in reactor PB, whereas the plasmid abundance did not, indicating transfer to other bacteria. A number of different 3‐CA degrading C. testosteroni strains carrying pNB2 could be isolated from reactor PB.
Conclusions: A successful plasmid‐mediated bioaugmentation was achieved with C. testosteroni being the dominant 3‐CA degrading pNB2 transconjugant species active in reactor PB.
Significance and Impact of the Study: The study underlines the potential of gene transfer to contribute to establishment and spread of genetic information in general, particularly emphasizing the spread of xenobiotic degrading potential by dissemination of catabolic genes.
Bioaugmentation by introduction of catabolic genes residing on mobile genetic elements into the microbial community of a soil or wastewater environment might be an alternative to bioaugmentation by ...addition of bacterial cells with chromosomally encoded catabolic genes. This study investigates the possibility to enhance degradation of the xenobiotic model compound 2,4-dichlorophenoxyacetic acid in a sequencing batch biofilm reactor (SBBR) by using the conjugative plasmid pJP4 carrying genes for 2,4-D degradation. After introduction of a plasmid donor strain to a lab-scale SBBR operated without 2,4-D, the number of plasmid-carrying cells first dropped, and then increased after switching to 2,4-D as the sole carbon source. The donor cells were unable to grow in the applied synthetic wastewater with 2,4-D as the sole carbon source. Transconjugants could be detected both by culture-dependent and culture-independent methods in the 2,4-D degrading biofilm. In contrast to 90% 2,4-D degradation in the bioaugmented reactor within 40 h, a control reactor which had not received the plasmid still contained 60% of the initial 2,4-D concentration after 90 h. This experiment clearly demonstrates the introduction of 2,4-D degradative genes into a microbial biofilm and indicates that horizontal gene transfer is a promising tool for bioaugmentation of reactors treating wastewater.
Direct photons were measured with the PHENIX experiment in
p
+
p
,
d
+
Au
, and Au+Au at
s
N
N
=
200
GeV
. To tackle the
p
T
region below 5 GeV/c, direct photons were measured through their internal ...conversion into
e
+
e
−
in Au+Au collisions.
We present azimuthal angular correlations between charged hadrons and energy deposited in calorimeter towers in central d+Au and minimum bias p+p collisions at sNN=200 GeV. The charged hadron is ...measured at midrapidity |eta|<0.35, and the energy is measured at large rapidity (-3.7<eta< -3.1, Au-going direction). An enhanced near-side angular correlation across | Delta eta|>2.75 is observed in d+Au collisions. Using the event plane method applied to the Au-going energy distribution, we extract the anisotropy strength v2 for inclusive charged hadrons at midrapidity up to pT=4.5 GeV/c. We also present the measurement of v2 for identified pi+ or - and (anti)protons in central d+Au collisions, and observe a mass-ordering pattern similar to that seen in heavy-ion collisions. These results are compared with viscous hydrodynamic calculations and measurements from p+Pb at sNN=5.02 TeV. The magnitude of the mass ordering in d+Au is found to be smaller than that in p+Pb collisions, which may indicate smaller radial flow in lower energy d+Au collisions.
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