21 research outputs found
Evaluation of Four Commonly Used DNA Barcoding Loci for Chinese Medicinal Plants of the Family Schisandraceae
Many species of Schisandraceae are used in traditional Chinese medicine and are faced with contamination and substitution risks due to inaccurate identification. Here, we investigated the discriminatory power of four commonly used DNA barcoding loci (ITS, trnH-psbA, matK, and rbcL) and corresponding multi-locus combinations for 135 individuals from 33 species of Schisandraceae, using distance-, tree-, similarity-, and character-based methods, at both the family level and the genus level. Our results showed that the two spacer regions (ITS and trnH-psbA) possess higher species-resolving power than the two coding regions (matK and rbcL). The degree of species resolution increased with most of the multi-locus combinations. Furthermore, our results implied that the best DNA barcode for the species discrimination at the family level might not always be the most suitable one at the genus level. Here we propose the combination of ITS+trnH-psbA+matK+rbcL as the most ideal DNA barcode for discriminating the medicinal plants of Schisandra and Kadsura, and the combination of ITS+trnH-psbA as the most suitable barcode for Illicium species. In addition, the closely related species Schisandra rubriflora Rehder & E. H. Wilson and Schisandra grandiflora Hook.f. & Thomson, were paraphyletic with each other on phylogenetic trees, suggesting that they should not be distinct species. Furthermore, the samples of these two species from the southern Hengduan Mountains region formed a distinct cluster that was separated from the samples of other regions, implying the presence of cryptic diversity. The feasibility of DNA barcodes for identification of geographical authenticity was also verified here. The database and paradigm that we provide in this study could be used as reference for the authentication of traditional Chinese medicinal plants utilizing DNA barcoding
Study on the Separate Characteristics of Oil Spill Driven by Combined Water and Wind in Braided Rivers
In general, there are many bifurcations in natural rivers. When the oil spilled accident occurred at the upstream of bifurcation and was not controlled in time, the pollution scale would be expanded and the treatment would become harder as the oil slick entered into braided river driven by combined water and wind. To Study the separate law at the bifurcation in rivers, a two-dimensional numerical simulation model of oil spilled was established by oil particle model theory on the basis of two-dimensional hydrodynamic model. The quantitative relationship between the oil separate ratio and the flux ratio, velocity ratio, width ratio was obtained driven by water. The wind effect on the proportion of oil separate was also discussed based on the oil spilled numerical simulation. This study will provide technical support for forecast and response of oil pollution in braided rivers
The Study on Transport Characteristic and Impact Factors of Spilled Oil on Open Channel of Water Transfer Project
In order to quickly respond to oily pollution incidents in water transfer projects, the author has adopted the two-dimensional hydrodynamic model, oil spill numerical model, combined with physical model test, to carry out quick prediction on the characteristic parameters of oil spill transport and impact factors. The research results show that: in the case of sudden outbreak of oil spill pollution on the open channels of water transfer projects, the oil slick transports about 1.15 times as fast as the central flow velocity; the change rate of the longitudinal length of the oil slick is 0.5 times of the central flow velocity at the cross section; in the case of sudden pollution, neither the transport distance of the oil slick nor its longitudinal length change rate is affected by oil spill quantity; the wind field has a greater influence on the transport distance of oil slick: when the wind direction is parallel with the flow, the wind field has little influence on the change rate of the longitudinal length of the oil slick; when the wind direction is perpendicular to the flow, the oil slick will be banked under the action of the wind field; According to the physical model test, different oil spill types will lead to different the change rate of the longitudinal length of the oil film. The research results of this paper can be used to realize quick prediction of the pollution range in the case of oil spill on open channel of water transfer project, and provide support for decision making in emergency treatment pollution control
Study on the Separate Characteristics of Oil Spill Driven by Combined Water and Wind in Braided Rivers
In general, there are many bifurcations in natural rivers. When the oil spilled accident occurred at the upstream of bifurcation and was not controlled in time, the pollution scale would be expanded and the treatment would become harder as the oil slick entered into braided river driven by combined water and wind. To Study the separate law at the bifurcation in rivers, a two-dimensional numerical simulation model of oil spilled was established by oil particle model theory on the basis of two-dimensional hydrodynamic model. The quantitative relationship between the oil separate ratio and the flux ratio, velocity ratio, width ratio was obtained driven by water. The wind effect on the proportion of oil separate was also discussed based on the oil spilled numerical simulation. This study will provide technical support for forecast and response of oil pollution in braided rivers
The Study on Transport Characteristic and Impact Factors of Spilled Oil on Open Channel of Water Transfer Project
In order to quickly respond to oily pollution incidents in water transfer projects, the author has adopted the two-dimensional hydrodynamic model, oil spill numerical model, combined with physical model test, to carry out quick prediction on the characteristic parameters of oil spill transport and impact factors. The research results show that: in the case of sudden outbreak of oil spill pollution on the open channels of water transfer projects, the oil slick transports about 1.15 times as fast as the central flow velocity; the change rate of the longitudinal length of the oil slick is 0.5 times of the central flow velocity at the cross section; in the case of sudden pollution, neither the transport distance of the oil slick nor its longitudinal length change rate is affected by oil spill quantity; the wind field has a greater influence on the transport distance of oil slick: when the wind direction is parallel with the flow, the wind field has little influence on the change rate of the longitudinal length of the oil slick; when the wind direction is perpendicular to the flow, the oil slick will be banked under the action of the wind field; According to the physical model test, different oil spill types will lead to different the change rate of the longitudinal length of the oil film. The research results of this paper can be used to realize quick prediction of the pollution range in the case of oil spill on open channel of water transfer project, and provide support for decision making in emergency treatment pollution control
Erosion Control Treatment Using Geocell and Wheat Straw for Slope Protection
Slope failure triggered by soil erosion under rainfall remains one of the most difficult problems in geotechnical engineering. Slope protection with planting vegetation can be used to reinforce the soil and stabilize the slope, but the early collapse of the planting soil before the complete growth of plants becomes a major issue for this method. This paper has proposed a composite soil treatment and slope protection method using the geocell structures and the wheat straw reinforcement. The geocell structures improve the stability of the planting soil and provide a stable and fixed environment for the vegetation, while the wheat straw reinforces the soil and also increases the fertility. The authors have performed a total of 9 experiments in this work that are classified into three groups, i.e., the unsupported slopes, the geocell reinforced, and the geocell and wheat straw composite reinforced with a consideration of three different rainfall intensities. The progressive slope failure development during the rainfall was assessed, as well as the soil erosion, the slope displacement, and the water content. The results show that the slope failure increases as the rainfall continues, and the soil degradation increases with the intensity of rainfall. The soil treatment using geocell improves the slope stability, but the geocell and wheat straw composite reinforcement has the best erosion control and slope protection
Reversible redox chemistry in azobenzene-based organic molecules for high-capacity and long-life nonaqueous redox flow batteries
Organic molecules are promising active materials for nonaqueous redox-flow batteries (RFBs), but suffer from poor cycling stability. Here, the authors introduce azobenzene-based molecules as new type of highly soluble and stable active materials to realize high-capacity and long-life nonaqueous RFBs
High-throughput solubility determination for data-driven materials design and discovery in redox flow battery research
Solubility is crucial for redox flow batteries as it affects their energy density. A data-driven approach based on AI/ML models can speed up the development of highly soluble redox active materials, but accurate solubility prediction remains elusive because of the lack of relevant databases. To overcome this deficiency, we developed a high-throughput experimentation process that combines a robotically controlled platform with high-throughput methodology to collect large-scale and high-quality solubility data. We demonstrate the potential utility and applicability of this high-throughput process by measuring the aqueous and non-aqueous solubilities of redox active materials and studying the effect of additives on their solubilities for both aqueous and non-aqueous redox flow battery applications. A redox flow battery based on our optimized negative electrolyte formulation and ferrocyanide positive electrolyte offers highly stable performance over 18 days (>100 cycles) with consistent capacity and a 24% boost in energy density
Plots of maximum intraspecific vs. minimum interspecific p-distances for single regions of Schisandraceae.
<p>Each dot represents a species for which two or more individuals were sampled. Dots above the diagonal line indicate the presence of a barcoding gap.</p
Optimized Electrolyte with High Electrochemical Stability and Oxygen Solubility for Lithium-Oxygen and Lithium-Air Batteries
Lithium-oxygen (Li-O-2) batteries with high reversibility require a stable electrolyte against the side reactions with Li-metal anode and reactive oxygen species. Moreover, an electrolyte that can effectively utilize the low partial pressure of oxygen in the atmosphere has significant effect on the practical application of Li-air batteries. In this study, a localized high-concentration electrolyte (LHCE) was developed using 1H,1H,5H-octafluoropentyl 1,1,2,2-tetrafluoroethyl ether (OTE) as a diluent, which satisfies all these conditions simultaneously. The OTE-based LHCE exhibits much improved electrochemical performance in Li-O-2 batteries and Li-air batteries in comparison to the conventional electrolyte and high-concentration electrolyte. The design principles of this electrolyte also provide important guidelines for research to further develop new electrolytes for Li-O-2 and Li-air batteries