26 research outputs found
A new phenolic glycoside and two new monoterpenoid furocoumarins from Aurantii Fructus Immaturus
<p>A new phenolic glycoside, citrauranoside A (<b>1</b>), and two new monoterpenoid furocoumarins, citraurancoumarin A (<b>2</b>) and citraurancoumarin B (<b>3</b>), along with four known compounds (<b>4–7</b>) were isolated from the young fruit of <i>Citrus aurantium</i> L. The structures were elucidated by their comprehensive analysis including 1D, 2DNMR, IR and mass spectra.</p
Toxicity effects of DnBP on biochemistry parameters of <i>E</i>. <i>fetida</i>.
<p>(a) Total protein content; (b) SOD activity; (c) POD activity; and (d) ROS activity were determined after treated for 7d, 14d, 21d and 28d in spiked natural soil CK, B-1, B-2, B-3, and B-4 (n = 4; error bars, SEM/mean values of standard errors). The spiked concentrations of DnBP were 0, 1, 2.5, 5, and 10 mg kg<sup>-1</sup> soil. Asterisk shows significant difference at <i>p</i><0.05 level compared to the control; double asterisks show significant difference at <i>p</i><0.01 level compared to the control.</p
Cytotoxicity of DnBP determined by flow cytometry assays.
<p>(a) coelomocyte apoptosis (a1,a2) stained with Annexin V-FITC and PI (Upper left quadrant, necrotic cells; upper right quadrant, late/secondary apoptotic cells; bottom left quadrant, live cells; and bottom right quadrant, early/primary apoptotic cells) in the 28th day and (b) lysosomal membrane stability characterized by NRR time in extruded coelomocyte of treated <i>E</i>. <i>fetida</i> in the 7th, 14th, 21st and 28th day after exposure in spiked natural soil CK, B-1, B-2, B-3, and B-4 for 28 days (n = 4; error bars, SEM). Refer other annotates to <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0151128#pone.0151128.g001" target="_blank">Fig 1</a>.</p
Genotoxicity of DnBP analyzed by comet assay.
<p>(a) length of tail; (b) tail DNA ratio; (c) tail moment and (d) olive tail moment of coelomocyte in treated <i>E</i>. <i>fetida</i> after treated for 7d, 14d, 21d and 28d in spiked natural soil CK, B-1, B-2, B-3, and B-4 (n = 4; error bars, SEM). Length of tail (TL) means tail length in arbitrary units; tail DNA ratio means relative ratio of DNA in the comet tail; tail moment (TM) means integrated value of DNA density multiplied by the migration distance; and Olive tail moment (OTM) means the product of the distance between the center of gravity of the head and the center of gravity of the tail and percent tail DNA. Refer other annotates to <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0151128#pone.0151128.g001" target="_blank">Fig 1</a>.</p
Promoter Effects on Nickel-Supported Magnesium Oxide Catalysts for the Carbon Dioxide Reforming of Methane
The
nickel catalysts supported on bare MgO and its binary Mg–Al,
Mg–La, and Mg–Fe metal oxides were prepared and used
for carbon dioxide reforming of methane to syngas. The effects of
Al, La, and Fe metal oxides on the structural properties, reducibility,
and metal–support interaction of the Ni catalysts supported
on MgO-based binary metal oxide were investigated. The X-ray powder
diffraction (XRD), transmission electron microscopy (TEM), and hydrogen
temperature-programmed reduction (H<sub>2</sub>-TPR) analyses show
that the nickel nanoparticles were highly dispersed on the supports.
It is found that the Al ions can be well-incorporated into the MgO
lattice to form uniform Mg–Al oxides, while isolated lanthanum
oxides and iron oxides were observed in the Mg–La and Mg–Fe
binary systems by TEM, respectively. Ni/Mg–Al metal oxide exhibits
greatly improved catalytic activity, owing to the formation of a homogeneous
Mg–Al oxide matrix with small particle sizes of Ni nanoparticles
compared to bare Ni/MgO. Very low conversions for both CH<sub>4</sub> and CO<sub>2</sub> were obtained on Ni/Mg–La and Ni/Mg–Fe
metal oxides, even at a high temperature of 800 °C, as a result
of the incomplete reduction of the nickel nanoparticles
Facile synthesis and wide-band electromagnetic wave absorption properties of carbon-coated ZnO nanorods
<p>In this work, a facile and scalable acetylene decomposition method was employed to synthesize carbon-coated ZnO (ZnO@C) nanorods. The characterization of morphology and structure analysis demonstrate that ZnO nanorod was well coated by an amorphous carbon shell with a thickness of about 20 nm. Comparted with ZnO, ZnO@C exhibit significantly enhanced microwave absorption properties. The effective absorption bandwidth with RL values exceeding –10 dB can reach 5.3 GHz for ZnO@C with a matching thickness of 2.5 mm. The excellent microwave absorption arose from enhanced dielectric loss caused by interfacial polarization, dipole polarization and the formation of conductive network.</p
Toxicity effects of di-(2-ethylhexyl) phthalate to <i>Eisenia fetida</i> at enzyme, cellular and genetic levels
<div><p>Di-(2-ethylhexyl) phthalate (DEHP) is a dominant phthalic acid ester (PAE) that has aroused public concern due to its resistance to degradation and its toxicity as an endocrine-disrupting compound. Effects of different concentrations of DEHP on <i>Eisenia fetida</i> in spiked natural soil have been studied in the body of the earthworm by means of soil cultivation tests 7, 14, 21 and 28 days after exposure. The results indicated that, in general, superoxide dismutase (SOD) activity, malondialdehyde (MDA) content, metallothionein (MT) content, the expression of heat shock protein 70 (HSP 70) and all the tested geno-toxicity parameters are promoted as time elapses and with increasing concentration of DEHP. However, peroxidase (POD) activity, neutral red retention time (NRRT) and mitochondrial membrane potential difference values were found to decrease even at a low concentration of DEHP of 1 mg kg<sup>-1</sup> soil (<i>p</i><0.05). Clear toxic effects of DEHP on <i>E</i>. <i>fetida</i> have been generally recognized by means of the disturbance of antioxidant enzyme activity/content and critical proteins, cell membrane and organelle disorder and DNA damage estimated by length of tail, tail DNA ratio, and tail moment parameters. A concentration of DEHP of 3 mg kg<sup>-1</sup> may be recommended as a precaution against the potential risk of PAEs in soils and for indicating suitable threshold values for other soil animals and soil micro-organisms.</p></div
Recycling Spent Cr Adsorbents as Catalyst for Eliminating Methylmercaptan
Waste
adsorbents generated from treating CrÂ(VI)-containing wastewater
are hazardous materials and generally landfilled or treated by acid
or base desorption, with concomitant high cost and toxic effects.
The present work shows that these Cr adsorbents can be reused as highly
efficient catalysts for treating sulfur-containing VOCs (CH<sub>3</sub>SH), not only avoiding the economic and environmental impact from
the conventional approaches, but also achieving the efficient treatment
of sulfur-containing waste gas. Importantly, these reused Cr adsorbents
exhibit enhanced activity and stability compared with the catalysts
reported elsewhere, indicating a new avenue of green chemistry. The
highly toxic adsorbed CrÂ(VI) species are reduced to a Cr<sub>2</sub>O<sub>3</sub> crystalline phase by calcination and finally immobilized
as a Cr<sub>2</sub>S<sub>3</sub> solid phase while converting and
eliminating CH<sub>3</sub>SH. Still, the presence of CrÂ(VI) species
on the reused Cr adsorbent provides enough reactive sites for reaction,
but high concentration of CrÂ(VI) species causes serious accumulation
of coke deposit on the catalyst, leading to fast deactivation of the
catalyst
Uptake of Arsenic(V) Using Alumina Functionalized Highly Ordered Mesoporous SBA-15 (Al<sub><i>x</i></sub>‑SBA-15) as an Effective Adsorbent
The SBA-15 (a mesoporous SiO<sub>2</sub> material) decorated with
10% aluminum (Al<sub>10</sub>-SBA-15) was found to be an excellent
adsorbent to remove AsÂ(V) from water. The highly dispersed aluminum
species have been obtained over the well-ordered mesoporous Al<sub>10</sub>-SBA-15 adsorbent and act as the active adsorption sites
for arsenicÂ(V) removal instead of SiO<sub>2</sub>. The adsorption
behavior of AsÂ(V) onto Al<sub>10</sub>-SBA-15 was investigated in
aqueous solution using various experimental parameters. The adsorption
data of AsÂ(V) could be fitted more successfully by the Langmuir isotherm
than the Freundlich isotherm model, and the pseudo-second-order equation
described this entire adsorption process well. It is found from the
analysis of kinetic data with the intraparticle diffusion mode that
both the boundary layer (film) diffusion and intraparticle diffusion
may contribute to the rate-limiting steps. Importantly, Al<sub>10</sub>-SBA-15 exhibits high arsenicÂ(V) removal in the wide pH range of
2.0–8.2 and can remove AsÂ(V) from water containing arsenate
of ≤2.235 mg·L<sup>–1</sup> to reach levels in
accordance with the regulations for drinking water purposes (<10
μg·L<sup>–1</sup>). Consequently, Al<sub>10</sub>-SBA-15 is believed to be an effective adsorbent for treating arsenate
contaminated wastewater