26 research outputs found
The molecular clouds in a section of the third Galactic quadrant: observational properties and chemical abundance ratio between CO and its isotopologues
We compare the observational properties between CO, CO, and
CO and summarize the observational parameters based on 7069 clouds
sample from the Milky Way Imaging Scroll Painting (MWISP) CO survey in a
section of the third Galactic quadrant. We find that the CO angular area
() generally increases with that of CO (), and the ratio of to is 0.38 by
linear fitting. We find that the CO and CO flux are tightly
correlated as with both fluxes
calculated within the CO-bright region. This indicates that the
abundance is a constant to be 6.5 for all samples under assumption of local thermodynamic equilibrium
(LTE). Additionally, we observed that the X-factor is approximately constant in
large sample molecular clouds. Similarly, we find with both fluxes calculated within
CO-bright region, which indicates that the abundance ratios stays the same value 9.7 across the
molecular clouds under LTE assumption. The linear relationships of vs. and vs.
hold not only for the CO-bright region or CO-bright region, but
also for the entire molecular cloud scale with lower flux ratio. The abundance
ratio inside clouds shows a strong
correlation with column density and temperature. This indicates that the
is dominated by a combination of chemical
fractionation, selectively dissociation, and self-shielding effect inside
clouds.Comment: 11 pages, 16 figures, 1 table, accepted by A
Corrosion inhibition of sulphate-reducing bacterial by Ag/Cu bimetallic nanoparticles synthesised from ginger extract
Overexpression of a MYB Family Gene, OsMYB6, Increases Drought and Salinity Stress Tolerance in Transgenic Rice
MYB transcription factors have been demonstrated to play key regulatory roles in plant growth, development and abiotic stress response. However, knowledge concerning the involvement of rice MYB genes in salinity and drought stress resistance are largely unknown. In the present study, we cloned and characterized the OsMYB6 gene, which was induced by drought and salinity stress. Subcellular localization of OsMYB6-YFP fusion protein in protoplast cells indicated that OsMYB6 was localized in the nucleus. Overexpression of OsMYB6 in rice did not suggest a negative effect on the growth and development of transgenic plants, but OsMYB6-overexpressing plants showed increased tolerance to drought and salt stress compared with wild-type plants, as are evaluated by higher proline content, higher CAT and SOD activities, lower REL and MDA content in transgenic plants under drought and salt stress conditions. In addition, the expression of abiotic stress-responsive genes were significantly higher in OsMYB6 transgenic plants than that in wild-type plants under drought and salt stress conditions. These results indicate that OsMYB6 gene functions as a stress-responsive transcription factor which plays a positive regulatory role in response to drought and salt stress resistance, and may be used as a candidate gene for molecular breeding of salt-tolerant and drought-tolerant crop varieties
Genetic analysis and fine mapping of the pubescence gene GL6 in rice (Oryza sativa L.)
Synthesis, Characterization, and Fluorescence Properties of Two New Heterocyclic Compounds Containing 1,5-Dioxaspiro Group
A precursor, C21H29NO8 (A1) was prepared by reactions of 1,1-dimethoxy-N,N-dimethylmethanamine and 1,5-dioxaspiro[5.5]undecane-2,4-dione. The new N-containing heterocyclic compound, C19H19NO4 (B1) was obtained by adding A1 into ethanol solution of o-toluidine. The crystal structure determination of two compounds were both found to belong to the triclinic P-1 space group. The precursor includes one (C2H8N)+ cation and one (C19H21O8)− anion, which constituted a chained structure by N–H···O intra- and intermolecular interactions. The title compound (B1) formed a 3D-network structure by weak C–H···O intermolecular interactions and π···π stacking interactions. The fluorescent behaviors of A1 and B1 in ethanol solution were discussed. The result shows that they exhibit blue and purplish blue emission, respectively
Novel Materials for Heavy Metal Removal in Capacitive Deionization
Heavy metals are considered a class of contaminant that can accumulate in the food chain and thus must be removed from contaminated media. Heavy metals can be removed by electrocoagulation, electroflotation, electrodialysis, capacitive deionization, and so on. Among the methods to remove heavy metals, capacitive deionization is one of the most attractive methods that can remove heavy metal ions without using a large volume of chemicals and producing a high number of heavy metals containing solid wastes. In this study, after a brief introduction to the mechanism of capacitive deionization, we focus on materials that have been developed as electrodes for heavy metal removal in capacitive deionization and summarize the latest advancements. Finally, with particular emphasis on material design, we provide some further insights in this area
Study of the Effect of Pyrolysis Temperature on the Cd2+ Adsorption Characteristics of Biochar
Rice husk and cotton straw were used to produce biochar under 300, 400, 500, 600, and 700 °C pyrolysis conditions, and the physicochemical properties of the obtained biochar samples were characterised. The effects of various adsorbent amounts, initial pH, and adsorption time on the Cd2+ adsorption performance were studied. The results showed that, at increasing pyrolysis temperatures, the biochar yield decreased, the ash content increased, the pH transitioned from acidic/neutral to basic/strongly basic, the biochar aromaticity gradually increased, and the biochar structure became more stable. In contrast, the hydrophilicity and polarity decreased, the specific surface area increased, and the number of oxygen-containing functional groups decreased. All these factors resulted in differences in the Cd2+ adsorption by the biochar samples. With increasing adsorbent content, the rate of Cd2+ adsorbed on the biochar gradually increased. The adsorption performance was optimal when the initial solution pH of the rice-husk and cotton-straw biochar samples was 5 and 6, respectively. The shortest time to achieve equilibrium was 30 min for rice-husk biochar, and 20 min for cotton-straw biochar. The Cd2+ adsorption data for both types of biochar were very well fitted with a pseudo-second-order kinetic model. Ion exchange and cation–π interactions may be the main factors influencing the Cd2+ adsorption by biochar. At the same time, the large specific surface area of biochar also plays a role in the Cd2+ adsorption