On 21 August 2009, the Airborne Detector for Energetic Lightning Emissions (ADELE), an array of six gamma‐ray detectors, detected a brief burst of gamma rays while flying aboard a Gulfstream V jet ...near two active thunderstorm cells. The duration and spectral characteristics of the event are consistent with the terrestrial gamma ray flashes (TGFs) seen by instruments in low Earth orbit. A long‐duration, complex +IC flash was taking place in the nearer cell at the same time, at a distance of ∼10 km from the plane. The sferics that are probably associated with this flash extended over 54 ms and included several ULF pulses corresponding to charge moment changes of up to 30 C km, this value being in the lower half of the range of sferics associated with TGFs seen from space. Monte Carlo simulations of gamma ray propagation in the Earth's atmosphere show that a TGF of normal intensity would, at this distance, have produced a gamma ray signal in ADELE of approximately the size and spectrum that was actually observed. We conclude that this was the first detection of a TGF from an aircraft. We show that because of the distance, ADELE's directional and spectral capabilities could not strongly constrain the source altitude of the TGF but that such constraints would be possible for TGFs detected at closer range.
Key Points
A terrestrial gamma ray flash has been observed from an aircraft for the first time
This terrestrial gamma ray flash (TGF) was associated with an unusual +IC flash
Compton scattering makes it hard to identify TGF source altitude at >5 km distance
We report the discovery of multiferroic behavior in double perovskite Y2NiMnO6. X-ray diffraction shows that the material has a centrosymmetric crystal structure of space group P2 1/n with Ni2+/Mn4+ ...ordering. This result is further confirmed by aberration-corrected scanning transmission electron microscopy combined with atomic resolution electron energy loss spectroscopy. The appearance of ferroelectric polarization coincides with the magnetic phase transition (∼67 K), which indicates that the ferroelectricity is driven by magnetism, and this is further confirmed by its strong magnetoelectric (ME) effect. We proposed the origin of the ferroelectricity is associated with the combination of Ni2+/Mn4+ charge ordering and the ↑↑↓↓ spin ordering. When compared with other known magnetic multiferroics, Y2NiMnO6 displays several attractive multiferroic properties, including high polarization (∼145 μC/m2), a high multiferroic transition temperature (∼67 K), and strong ME coupling (∼21%).
Hydrogen production by biomass gasification in supercritical water is a promising technology for utilizing high moisture content biomass, but reactor plugging is a critical problem when feedstocks ...with high biomass content are gasified. The objective of this paper is to prevent the plugging problem by studying the effects of the various parameters on biomass gasification in supercritical water. These parameters include pressure, temperature, residence time, reactor geometrical configuration, reactor types, heating rate, reactor wall properties, biomass types, biomass particle size, catalysts and solution concentration. Biomass model compounds (glucose, cellulose) and real biomass are used in this work. All the biomasses have been successfully gasified and the product gas is composed of hydrogen, carbon dioxide, methane, carbon monoxide and a small amount of ethane and ethylene. The results show that the gas yield of biomass gasification in supercritical water is sensitive to some of the parameters and the ways of reducing reactor plugging are obtained.
Lactic Acid Bacteria (LAB) regulate and maintain the stability of healthy microbial flora, inhibit the adhesion of pathogenic bacteria and promote the colonization of beneficial micro‐organisms. The ...drug resistance and pathogenicity of Salmonella enteritis SE47 isolated from retail eggs were investigated. Meanwhile, Enterococcus faecalis L76 and Lactobacillus salivarius LAB35 were isolated from intestine of chicken. With SE47 as indicator bacteria, the diameters of L76 and LAB35 inhibition zones were 12 mm and 8·5 mm, respectively, by agar inhibition circle method, which indicated that both of them had inhibitory effect on Salmonella, and L76 had better antibacterial effect; two chicken‐derived lactic acid bacteria isolates and Salmonella SE47 were incubated with Caco‐2. The adhesion index of L76 was 17·5%, which was much higher than that of LAB35 (10·21%) and SE47 (4·89%), this experiment shows that the higher the bacteriostatic effect of potential probiotics, the stronger the adhesion ability; then Caco‐2 cells were incubated with different bacteria, and the survival of Caco‐2 cells was observed by flow cytometry. Compared with Salmonella SE47, the results showed that lactic acid bacteria isolates could effectively protect Caco‐2 cells; finally, after different bacteria incubated Caco‐2 cells, according to the cytokine detection kit, the RNA of Caco‐2 cells was extracted and transcribed into cDNA, then detected by fluorescence quantitative PCR, the results showed that L76 could protect Caco‐2 cells from the invasion of Salmonella SE47, with less cell membrane rupture and lower expression of MIF and TNF genes. Therefore, the lactic acid bacteria isolates can effectively inhibit the adhesion of Salmonella and protect the integrity of intestinal barrier.
Significance and Impact of the Study: We evaluated the effect of Lactobacillus from chicken on Salmonella. The results showed that both Enterococcus faecalis L76 and Lactobacillus salivarius LAB35 could effectively inhibit Salmonella SE47, and the inhibitory effect of L76 was better than LAB35. Chicken derived lactic acid bacteria can effectively protect the integrity of cell membrane from Salmonella invasion by adhering to cells. Lactobacillus can effectively antagonize the immune regulation of Salmonella in vitro. It was found that L76 had better immunomodulatory effect than LAB35.
The quantum entangled J/ψ→Σ^{+}Σover ¯^{-} pairs from (1.0087±0.0044)×10^{10} J/ψ events taken by the BESIII detector are used to study the nonleptonic two-body weak decays Σ^{+}→nπ^{+} and Σover ...¯^{-}→nover ¯π^{-}. The CP-odd weak decay parameters of the decays Σ^{+}→nπ^{+} (α_{+}) and Σover ¯^{-}→nover ¯π^{-} (αover ¯_{-}) are determined to be 0.0481±0.0031_{stat}±0.0019_{syst} and -0.0565±0.0047_{stat}±0.0022_{syst}, respectively. The decay parameter αover ¯_{-} is measured for the first time, and the accuracy of α_{+} is improved by a factor of 4 compared to the previous results. The simultaneously determined decay parameters allow the first precision CP symmetry test for any hyperon decay with a neutron in the final state with the measurement of A_{CP}=(α_{+}+αover ¯_{-})/(α_{+}-αover ¯_{-})=-0.080±0.052_{stat}±0.028_{syst}. Assuming CP conservation, the average decay parameter is determined as ⟨α_{+}⟩=(α_{+}-αover ¯_{-})/2=-0.0506±0.0026_{stat}±0.0019_{syst}, while the ratios α_{+}/α_{0} and αover ¯_{-}/αover ¯_{0} are -0.0490±0.0032_{stat}±0.0021_{syst} and -0.0571±0.0053_{stat}±0.0032_{syst}, where α_{0} and αover ¯_{0} are the decay parameters of the decays Σ^{+}→pπ^{0} and Σover ¯^{-}→pover ¯π^{0}, respectively.
Heat shock proteins (HSPs) participate in diverse physiological processes in insects, and HSP70 is one of the most highly conserved proteins in the HSP family. In this study, full-length cDNAs of ...three HSP70 genes (Lthsc70, Lthsp701, and Lthsp702) were cloned and characterized from Liriomyza trifolii, an important invasive pest of vegetable crops and horticultural crops worldwide. These three HSP70s exhibited signature sequences and motifs that are typical of the HSP70 family. The expression patterns of the three Lthsp70s during temperature stress and in different insect development stages were studied by real-time quantitative PCR. Lthsp701 was strongly induced by high- and low-temperature stress, but Lthsc70 and Lthsp702 were not very sensitive to temperature changes. All three Lthsp70s were expressed during insect development stages, but the expression patterns were quite different. The expression of Lthsc70 and Lthsp702 showed significant differences in expression during leafminer development; Lthsc70 was most highly expressed in female adults, whereas Lthsp702 was abundantly expressed in larvae and prepupae. Lthsp701 expression was not significantly different among leafminer stages. These results suggest that functional differentiation within the LtHSP70 subfamily has occurred in response to thermal stress and insect development.
The potential impact of carbon nanotubes (CNTs) on human health and the environment is receiving more and more attention. The high surface area of CNTs tends to adsorb a large variety of toxic ...chemicals, which may enhance the toxicity of CNTs and/or toxic chemicals. In this study, adsorption and desorption of atrazine on carbon nanotubes from aqueous solution were studied through batch reactors. The adsorption equilibrium isotherms were nonlinear and were fitted by Freundlich, Langmuir, and Polanyi–Manes models. It was found that the Polanyi–Manes model described the adsorption process better than other two isotherm models. Together with the “characteristic curve,” the Polanyi adsorption potential theory is applicable to describe the adsorption process of atrazine on CNTs. Thermodynamic calculations indicated that the adsorption reaction of atrazine on CNTs is spontaneous and exothermic. The desorption data showed that no significant desorption hysteresis occurred. High adsorption capacity and adsorption reversibility of atrazine on CNTs suggest that CNTs have high health and environmental risks, whereas they have potential applications for atrazine removal from water.
Repetitive adsorption/desorption of atrazine on CNTs at three initial concentrations: 6.9 (■), 16.2 (▴), and 30.6 mg/L (●), the corresponding open symbols represent the desorption processes after the last adsorption step, respectively: (A) SMWNT20; (B) r-MWNT.
Using (10087±44)×10^{6} J/ψ events collected with the BESIII detector, numerous Ξ^{-} and Λ decay asymmetry parameters are simultaneously determined from the process J/ψ→Ξ^{-}Ξover ...¯^{+}→Λ(pπ^{-})π^{-}Λover ¯(nover ¯π^{0})π^{+} and its charge-conjugate channel. The precisions of α_{Λ0} for Λ→nπ^{0} and αover ¯_{Λ0} for Λover ¯→nover ¯π^{0} compared to world averages are improved by factors of 4 and 1.7, respectively. The ratio of decay asymmetry parameters of Λ→nπ^{0} to that of Λ→pπ^{-}, ⟨α_{Λ0}⟩/⟨α_{Λ-}⟩, is determined to be 0.873±0.012_{-0.010}^{+0.011}, where the first and the second uncertainties are statistical and systematic, respectively. The ratio is smaller than unity more than 5σ, which signifies the existence of the ΔI=3/2 transition in Λ for the first time. Besides, we test for CP symmetry in Ξ^{-}→Λπ^{-} and in Λ→nπ^{0} with the best precision to date.
Hydrogen production by biomass gasification in supercritical water (SCW) is a promising technology for utilizing high moisture content biomass, but reactor plugging is a critical problem for biomass ...gasification in the tubular reactor. A novel SCW fluidized bed system for biomass gasification was developed successfully in State Key Laboratory of Multiphase Flow in Power Engineering (SKLMF) to prevent the plugging and it was designed for the temperature up to 923
K and the pressure up to 30
MPa. Model compound (glucose) and real biomass (corn cob) were gasified under SCW conditions to generate hydrogen-rich fuel gas and a performance testing of the new SCW fluidized bed system was conducted. The product gas composed of H
2, CH
4, CO
2, CO and small amount of C
2H
4 and C
2H
6 was obtained. The effects of solution concentration, temperature, pressure and oxidant concentration on gasification were studied. 30
wt% glucose and 18
wt% corn cob feedstocks were continually and stably gasified and reactor plugging was not observed. The results showed that using fluidized bed reactor for biomass gasification in SCW has many advantages and good prospects.
Secondary organic aerosol (SOA) is an important constituent of airborne fine particles. PM2.5 (particles with aerodynamic diameters≤2.5μm) samples were collected at a mountainous site in Hong Kong in ...autumn of 2010, and analyzed for SOA tracers. Results indicated that the concentrations of isoprene SOA tracers (54.7±22.7ng/m3) and aromatics SOA tracers (2.1±1.6ng/m3) were on relatively high levels in Hong Kong. Secondary organic carbon (SOC) derived from isoprene, monoterpenes, sesquiterpenes and aromatics was estimated with the SOA tracer based approach, which constituted 0.35±0.15μg/m3 (40.6±5.7%), 0.20±0.03μg/m3 (30.4±5.5%), 0.05±0.02μg/m3 (5.6±1.7%) and 0.26±0.20μg/m3 (21.3±8.2%) of the total estimated SOC. Biogenic SOC (0.60±0.18μg/m3) dominated over anthropogenic SOC (0.26±0.20μg/m3) at this site. In addition to the total estimated SOC (17.8±4.6% of organic carbon (OC) in PM2.5), primary organic carbon (POC) emitted from biomass burning also accounted for a considerable proportion of OC (11.6±3.2%). Insight into the OC origins found that regional transport significantly (p<0.05) elevated SOC from 0.37±0.17 to 1.04±0.39μg/m3. Besides, SOC load could also increase significantly if there was influence from local ship emission. Biomass burning related POC in regional air masses (0.81±0.24μg/m3) was also higher (p<0.05) than that in samples affected by local air (0.29±0.35μg/m3). Evidences indicated that SOA formation was closely related to new particle formation and the growth of nucleation mode particles, while biomass burning was responsible for some particle burst events in Hong Kong. This is the first SOA study in afforested areas of Hong Kong.
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•First study on speciated SOA in mountainous area of Hong Kong.•Regional transport from mainland China elevated SOC and POC in Hong Kong.•SOA formation related to new particle formation and growth.
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