Photocatalytic Antifouling Graphene Oxide-Mediated Hierarchical Filtration Membranes with Potential Applications on Water Purification

Graphene oxide-based filtration membranes with photocatalytic antifouling function have been successfully synthesized by a two-step method for the first time. First, graphene oxide particles composite sheets are prepared by decorating graphene oxide sheets with appropriate amount of TiO₂ nanoparticles, which can be assembled into filtration membranes with suitable permeation and retention rates. Then, an additional TiO₂ particle layer (P25) with strong photocatalysis activity is coated on these films by filtration, forming hierarchical structure membranes. The filtration properties of the as-obtained films are investigated by treating dye solution, and the results demonstrate that these membranes possess favorable photocatalytic antifouling function under UV light irradiation, which can maintain the clean films and their filtration properties, broadening the horizon for the vast use of these graphene-involved films in water purification

Interactions of Bis(2,4,4-trimethylpentyl)dithiophosphinate with Trivalent Lanthanides in a Homogeneous Medium: Thermodynamics and Coordination Modes

Complexation of trivalent lanthanides with a sulfur-bearing ligand, bis­(2,4,4-trimethylpentyl) dithiophosphinate, was studied in ethanol under identical conditions by optical spectroscopy, microcalorimetry, luminescence lifetime measurement, and extended X-ray absorption fine structure (EXAFS). Three successive complexes, LnL²⁺, LnL₂⁺, and LnL₃, where Ln and L denote the trivalent lanthanide and the dithiophosphinate ligand, respectively, formed in the solution. In contrast to the general findings that heavier lanthanides form stronger complexes due to the lanthanide contraction effect, the complexation strength between Ln­(III) and dithiophosphinate first increases from La­(III) to Nd­(III) and then decreases gradually toward heavier Ln­(III) across the lanthanide series. This trend agrees well with the results of solvent extraction using the same ligand as an extractant. The complexation is driven by highly positive entropies and opposed by endothermic enthalpies. The enthalpies of complexation become less endothermic from lighter to heavier Ln­(III), suggesting that less energy is required for desolvation for the complexation of heavier Ln­(III). EXAFS study shows that, from lighter to heavier Ln­(III), the number of sulfur atoms in the primary coordination sphere decreases while the number of oxygen atoms increases, which confirms that fewer solvent molecules are desolvated from heavier Ln­(III) during the complexation process. A correlation between the thermodynamics trends and the coordination modes has thereby been well established

Additional file 1: of An inappropriate pacing threshold increase after repeated electrical storm in a patient with implantable cardioverter defibrillator

I. 14 and 28 Oct, 2015 in 4 weeks post-first implantation follow-up. II.16, 18, 22, 24 and 30 Nov, 2015 in 2 months post- first implantation follow-up. III.1 and 3 Dec, 2015 in 2 months post- first implantation follow-up. IV.8, 9 and 16 Dec, 2015 in two weeks post- second implantation follow-up. V. 9 Mar and 13 Apr, 2016 in 3–4 months post- second implantation follow-up. VI. 9 Nov, 2016 in 9 months post- second implantation follow-up. VII. 14 Jun, 2017 in 18 months post- second implantation follow-up. VIII. 27 Sep, 2017 in 22 months post- second implantation follow-up. Initial threshold of device interrogation was respectively 2.37 V/0.5 ms, 2.75 V/0.5 ms, and 3.75 V/1.0 ms in 2, 4 and 9 weeks post- implantation. Recent device interrogation showed a ventricular sensing of 8.9 mV, 7.9 mV and 9.1 mV, a pacing threshold of 1.75 V/0.5 ms, 1.5 V/1.0 ms and 1.5 V/1.0 ms at 13, 20, 24 months post-implantation follow-up. (DOCX 902 kb

Factor and Idiosyncratic Empirical Processes

<p>The distributions of the common and idiosyncratic components for an individual variable are important in forecasting and applications. However, they are not identified with low-dimensional observations. Using the recently developed theory for large dimensional approximate factor model for large panel data, the common and idiosyncratic components can be estimated consistently. Based on the estimated common and idiosyncratic components, we construct the empirical processes for estimation of the distribution functions of the common and idiosyncratic components. We prove that the two empirical processes are oracle efficient when <i>T</i> = <i>o</i>(<i>p</i>) where <i>p</i> and <i>T</i> are the dimension and sample size, respectively. This demonstrates that the factor and idiosyncratic empirical processes behave as well as the empirical processes pretending that the common and idiosyncratic components for an individual variable are directly observable. Based on this oracle property, we construct simultaneous confidence bands (SCBs) for the distributions of the common and idiosyncratic components. For the first-order consistency of the estimated distribution functions, <math><mrow><msqrt><mi>T</mi></msqrt><mo>=</mo><mi>o</mi><mrow><mo>(</mo><mi>p</mi><mo>)</mo></mrow></mrow></math> suffices. Extensive simulation studies check that the estimated bands have good coverage frequencies. Our real data analysis shows that the common-component distribution has a structural change during the crisis in 2008, while the idiosyncratic-component distribution does not change much. Supplementary materials for this article are available online.</p

Variability of Levoglucosan in Precipitation in Lhasa as a Proxy for Tracing Vegetation Fires

Levoglucosan has been extensively used as a biomarker for tracing vegetation fire emissions in atmospheric aerosols, ice cores, and lake sediments. Precipitation can scavenge levoglucosan from the atmosphere to the Earth’s surface. However, almost no previous research has investigated the variability of levoglucosan in precipitation. This research reports levoglucosan records in precipitation samples collected from March 2018 to September 2019 in Lhasa, on the southern Tibetan Plateau. Although the event-based levoglucosan variations seem random, the variability on monthly or seasonal time scales is highly correlated to vegetation fire changes along the Himalayas and surrounding regions. In addition, extreme wildfires in southern Central Asia also affect levoglucosan records in precipitation at Lhasa, especially during the summer. Our results indicate that local vegetation fires are not the major sources of levoglucosan in precipitation in Lhasa. In addition, the annual levoglucosan flux at Lhasa is much higher than that in ice cores on the Tibetan Plateau. This study provides important insights into levoglucosan records in precipitation over the Tibetan Plateau, highlighting how levoglucosan variations could reflect fire changes from a single event to seasonal or annual time scales

Nonsynonymous substitution (dN), synonymous substitution (dS), and dN/dS values for individual Saxifragales genes and groups of genes.

<p>*Without the <i>rpl22</i> and <i>rpl32</i> genes; **without the <i>rps18</i> gene.</p

Comparison of junction positions between single copy and IR regions among four Saxifragales genomes and <i>Vitis vinifera</i>.

<p>Abbreviations - LF: <i>Liquidambar formosana</i>; PO: <i>Paeonia obovata</i>; SS: <i>Sedum sarmentosum</i>; PC: <i>Penthorum chinense</i>; and VV: <i>Vitis vinifera</i>.</p

Negative correlation between nonsynonymous substitution (dN) values and chloroplast genome size.

<p>The nonsynonymous substitution values are based on an analysis of all protein-coding genes, except for <i>rpl32</i>, <i>infA</i>, <i>rpl22</i>, and <i>rps18</i>. </p

Hexachlorocyclohexanes in Tree Bark across Chinese Agricultural Regions: Spatial Distribution and Enantiomeric Signatures

The environmental issue caused by atmospheric hexachlorocyclohexanes (HCHs) has been a worldwide concern due to their long-range transport potential. Tree bark is an excellent passive sampler for monitoring atmospheric pollutants. In this study, bark samples from agricultural regions across China were collected and analyzed to elucidate the contamination status of atmospheric HCHs and the enantiomeric composition of chiral α-HCH. Average contents of α-HCH, β-HCH, γ-HCH, δ-HCH, and ∑HCHs in bark were 1.16, 2.51, 1.67, 0.368, and 5.71 ng/g (dry basis), respectively. Jing-Jin-Tang region was identified as the “hot-spot” of bark HCHs in China. Their residues were likely from the combined sources of historical applications of technical HCHs and lindane through long-distance transport. HCH contents were found inversely correlated with annual precipitation and temperature, but positively correlated with PM10 or PM2.5 due to the bioaccumulation of both vapor- and particle-phase HCHs by tree bark. Most bark samples preferentially accumulated (+)-α-HCH, and the enantiomeric fractions (EFs) of α-HCH were positively correlated with α-HCH concentrations and the elevations of sampling locations. Compared to atmospheric analysis, tree bark analysis and enantiomeric signatures provide valuable time-integrated information on the spatial distribution and transport pathways of atmospheric HCHs on the national scale in China