Double neutron star (DNS) merger events are promising candidates of short gamma-ray burst (sGRB) progenitors as well as high-frequency gravitational wave (GW) emitters. On August 17, 2017, such a ...coinciding event was detected by both the LIGO-Virgo gravitational wave detector network as GW170817 and Gamma-Ray Monitor on board NASA's Fermi Space Telescope as GRB 170817A. Here, we show that the fluence and spectral peak energy of this sGRB fall into the lower portion of the distributions of known sGRBs. Its peak isotropic luminosity is abnormally low. The estimated event rate density above this luminosity is at least Formula: see text Gpc
yr
, which is close to but still below the DNS merger event rate density. This event likely originates from a structured jet viewed from a large viewing angle. There are similar faint soft GRBs in the Fermi archival data, a small fraction of which might belong to this new population of nearby, low-luminosity sGRBs.
•Ag-doping in TiO2 can preserve the anatase form to higher temperature.•Ag-doped TiO2 samples can absorb both UV and visible light.•The band gap energy of the sample significantly reduced after ...Ag-doping.•Ag-doped TiO2 samples effective for visible light-induced reduction of Cr(VI).
Ag-doped TiO2 nanomaterials (Ag–TiO2) were prepared by a sol–gel method. The structures of Ag–TiO2 nanomaterials were characterized by X-ray diffraction (XRD), UV–vis diffuse reflectance spectra (DRS), X-ray photoluminescence (PL) spectroscopy, X-ray photoelectron spectroscopy (XPS), thermogravimetry and differential thermal analysis (TG-DTA), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscope (TEM), scanning electron microscopy (SEM) and nitrogen adsorption–desorption isotherms. The photocatalytic activities were checked through the photocatalytic reduction of Cr(VI) as a model compound under visible light irradiation. The results showed that the Ag doping and the calcination temperature played an important role on the microstructure and photocatalytic activity of the samples. Ag-doped TiO2 samples calcinated at 400°C exhibits higher photocatalytic activity than that of the other samples under visible light irradiation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Carbon-coated Fe Fe(C) nanocapsules were synthesized by a modified arc-discharge method, and their microstructure and electromagnetic (EM) properties (2-18 GHz) were investigated by means of ...transmission electron microscopy, Raman spectroscopy and a network analyser. The reflection loss R of less than -20 dB was obtained in the frequency range 3.2-18 GHz. A minimum reflection loss of -43.5 dB was reached at 9.6 GHz with an absorber thickness of 3.1 mm. The in-depth study of relative complex permittivity and permeability reveals that the excellent microwave absorption properties are a consequence of a proper EM match in microstructure, a strong natural resonance, as well as multi-polarization mechanisms, etc.
(N, S and C) co-doped TiO2 samples show good photocatalytic activity for Cr(VI) reduction under visible light irradiation.
•(N, S and C) co-doping in TiO2 can preserve the anatase form to higher ...temperature.•(N, S and C) co-doped TiO2 samples can absorb both UV and visible light.•The band gap energy of the sample significantly reduced after (N, S and C) co-doping.•(N, S and C) co-doped TiO2 samples effective for visible light induced reduction of Cr(VI).
The (N, S and C) co-doped TiO2 samples (NSC-TiO2) were synthesized by the sol–gel method combining with the high energy ball milling method calcined at the different temperature (400–700°C), employing butyl titanate as the titanium source and thiourea as the doping agent. The structures of NSC-TiO2 samples were characterized by X-ray diffraction (XRD), UV–vis diffuse reflectance spectra (DRS), X-ray photoluminescence (PL) spectroscopy, X-ray photoelectron spectroscopy (XPS), thermogravimetry and differential thermal analysis (TG–DTA), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscope (TEM), scanning electron microscopy (SEM) and nitrogen adsorption–desorption isotherms. The photocatalytic activities were checked through the photocatalytic reduction of Cr(VI) as a model compound under visible light irradiation. The results showed that the (N, S and C) co-doping and the calcination temperature played important role on the microstructure and photocatalytic activity of the samples. According to XPS spectra, sulfur was mainly attributed to the TiOS bond; nitrogen was ascribed to the TiON and TiN bonds; carbon was assigned to the TiOC bond in the NSC-TiO2 samples. (N, S and C) co-doped TiO2 samples calcinated at 500°C exhibits higher photocatalytic activity than that of the other samples under visible light irradiation, which can be attributed to the synergic effect of its enhancing crystallization of anatase and (N, S and C) co-doping.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Iron (Fe) and nickel (Ni) nanoparticles were prepared by the DC arc-discharge method in a mixture of hydrogen and argon gases, using bulk metals as the raw materials. The microstructure of core/shell ...(metal/metal oxide) in nanoparticle formed after
in situ passivation process. The complex electromagnetic parameters (permittivity
ε
r
=
ε
r
′
+
i
ε
r
″
and permeability
μ
r
=
μ
r
′
+
i
μ
r
″
) of the paraffin-mixed nanocomposite samples (paraffin:nanoparticles=1:1 in mass ratio) were measured in the frequency range of 2–18
GHz. The polarization mechanisms of the space charge and dipole coexist in both the Fe and Ni nanoparticles. The orientational polarization is a particular polarization for Fe nanoparticles and brings a relatively higher dielectric loss. Natural resonance is the main reason for magnetic loss and the corresponding frequencies are 11.6 and 5.2
GHz for the Fe and Ni nanoparticles, respectively. The paraffin composite with Fe nanoparticles provided excellent microwave absorption properties (reflection loss <−20
dB) in the range 6.8–16.6
GHz over the absorber thickness of 1.1–2.3
mm.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Fe, N and C tri-doped polymorphic TiO2 nano-materials show good photocatalytic activity for Cr(VI) reduction under visible light irradiation.
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•Fe, N and C atoms were successfully ...tri-doped into the nanostructures of Fe-N-C-TiO2.•The band gap energy of Fe-N-C-TiO2 reduced after (Fe, N and C) tri-doping.•Fe, N and C tri-doping in polymorphic TiO2 were effective for the photocatalytic reduction of Cr(VI).
The (Fe, N and C) tri-coped polymorphic TiO2 (Fe-N-C-TiO2), containing anatase, rutile and brookite phase, were synthesized by a hydrothermal method. The tri-coped polymorphic TiO2 were characterized in detail by several techniques in terms of their structure, composition, optics, morphology, surface area, and so on. The photocatalytic activities of Fe-N-C-TiO2 nano-materials were examined under visible light illumination using Cr(VI) as target pollutant. The results showed that Fe/Ti weight ratio crucially determines the photocatalytic activity of Fe-N-C-TiO2 nano-materials. Fe-N-C-TiO2 nano-materials with Fe/Ti weight ratio of 0.30% exhibits highest photocatalytic activity than that of the other nano-materials under visible light irradiation, which can be attributed to the synergic effect of the higher BET surface area, separation rate of electron-hole pairs, more number of surface absorbed hydroxyl groups (OH), stronger absorption in the visible-light region and optimum Fe/Ti weight ratio.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Microbial communities are believed to outperform monocultures in the complete catabolism of organic pollutants via reduced metabolic burden and increased robustness to environmental challenges; ...however, the interaction mechanism in functional microbiomes remains poorly understood. Here, three functionally differentiated activated sludge microbiomes (S1: complete catabolism of sulfamethoxazole (SMX); S2: complete catabolism of the phenyl part of SMX (phenyl-SMX) with stable accumulation of its heterocyclic product 3-amino-5-methylisoxazole (3A5MI); A: complete catabolism of 3A5MI rather than phenyl-SMX) were enriched. Combining time-series cultivation-independent microbial community analysis, DNA-stable isotope probing, molecular ecological network analysis, and cultivation-dependent function verification, we identified key players involved in the SMX degradation process. Paenarthrobacter and Nocardioides were primary degraders for the initial cleavage of the sulfonamide functional group (−C–S–N– bond) and 3A5MI degradation, respectively. Complete catabolism of SMX was achieved by their cross-feeding. The co-culture of Nocardioides, Acidovorax, and Sphingobium demonstrated that the nondegraders Acidovorax and Sphingobium were involved in the enhancement of 3A5MI degradation. Moreover, we unraveled the internal labor division patterns and connections among the active members centered on the two primary degraders. Overall, the proposed methodology is promisingly applicable and would help generate mechanistic, predictive, and operational understanding of the collaborative biodegradation of various contaminants. This study provides useful information for synthetic activated sludge microbiomes with optimized environmental functions.
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The La and C co-doped anatase TiO2 nano-materials show good photocatalytic activity for Cr(VI) reduction under visible light irradiation. Display omitted
•LaC co-doping in TiO2 inhibited the anatase ...to rutile phase transformation.•The surface hydroxyl content increased after LaC co-doping.•LaC co-doping in TiO2 were effective for the photocatalytic reduction of Cr(VI).
The La and C co-doped anatase TiO2 nano-materials were synthesized by a hydrothermal method. The structures of La and C co-doped TiO2 were characterized by XRD, FT-IR, XPS, DRS, SEM and nitrogen adsorption–desorption isotherms. The results indicated that pH values have a greater effect on the crystalline phase, crystal size and crystallinity degree of TiO2. The La and C co-doping could inhibit the phase transformation and crystallite growth of TiO2. The photocatalytic activities of La and C co-doped TiO2 for photocatalytic reduction of Cr(VI) under visible light irradiation using different La contents were also studied. The La and C co-doped TiO2 nano-materials with La:Ti weight ratio of 0.3 exhibits the highest photocatalytic activity for Cr(VI) photocatalytic reduction under visible light irradiation, which can be attributed to the synergic effect of the higher BET surface area, surface hydroxyl content and optimum La contents.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Aim To analyse the computed tomography (CT) imaging features of patients with adrenal schwannoma. Materials and methods Eight cases of adrenal schwannoma confirmed by histopathology were included in ...this study. All eight patients had undergone multiphase CT examinations. The features of the adrenal schwannoma in the CT images were analysed retrospectively in detail, including size, shape, margin, radiodensity, calcification, and enhancement pattern. Results There were six male and two female patients, with a median age of 44.5 years (range, 25–52 years). Two patients complained of right flank pain, and two with left upper abdominal discomfort, while the remaining patients were diagnosed by routine ultrasound examinations. On unenhanced CT images, all cases of adrenal schwannoma were well circumscribed, rounded or oval, heterogeneous masses with cystic components, with two cases exhibiting calcification, and three cases with septa. On enhanced CT images, all cases displayed mild heterogeneous enhancement of the tumour during the arterial phase, and progressive enhancement during the portal venous phase and equilibrium phase. Conclusion Adrenal schwannoma commonly presents as a well-defined unilateral mass with cystic degeneration, septa, and a characteristic progressive contrast-enhancement pattern on multiphase enhanced scans.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
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