406 research outputs found
Design charts for contaminant transport through slurry trench cutoff walls
Slurry trench cutoff walls with low-permeability backfill material, such as soil-bentonite and slag-cement-bentonite, are used widely for containment of subsurface pollution. In the design of slurry walls the potential service life for a given thickness or the wall thickness for a target service life are typically determined via analyses of one-dimensional contaminant transport. The difficulty of selecting appropriate inlet and outlet boundary conditions and the mathematical complexity of analytical solutions hinder engineers in undertaking a contaminant transport analysis–based design. Design charts for nondimensionalized effluent flux are presented by developing and using an analytical solution. The methodologies of using these charts in design are demonstrated
Investigate the plasmonic enhanced solar photothermal effect of gold nanorod nanofilm
Gold nanospheres (Au NSs) and gold nanorods (Au NRs) are traditional noble
metal plasmonic nanomaterials. Particularly, Au NRs with tunable longitudinal
plasmon resonance from visible to the near infrared (NIR) range were suitable
for high efficient photothermal applications due to extended light receiving
range. In this work, we synthesized Au NRs and Au NSs of similar volume, and
subsequently developed them into Au NR/PVDF and Au NS/PVDF nanofilm, both of
which exhibited excellent solar photothermal performance evaluated by solar
photothermal experiments. We found that Au NR/PVDF nanofilm showed higher solar
photothermal performance than Au NS/PVDF nanofilm. Through detailed analysis,
such as morphological characterization, optical measurement, and finite element
method (FEM) modeling, we found that the plasmonic coupling effects inside the
aggregated Au NRs nanoclusters contributed to the spectral blue-shifts and
intensified photothermal performance. Compare to Au NS/PVDF nanofilms, Au
NR/PVDF nanofilm exhibited higher efficient light-to-heat conversion rate,
because of the extended light receiving range and high absorbance, as the
result of strong plasmonic interactions inside nanoclusters, which was further
validated by monochromatic laser photothermal experiments and FEM simulations.
Our work proved that the Au NRs have huge potential for plasmonic solar
photothermal applications, and are envisioned for novel plasmonic applications
Pollen Viability, Pistil Receptivity, and Embryo Development in Hybridization of Nelumbo nucifera Gaertn
Seed set is usually low and differs for different crosses of flower lotus (Nelumbo nucifera Gaertn.). The reasons remain unknown, and this has a negative impact on lotus breeding. To determine the causes, we carried out two crosses of flower lotus, that is, “Jinsenianhua” × “Qinhuaihuadeng” and “Qinhuaihuadeng” × “Jinsenianhua” and pollen viability, pistil receptivity, and embryo development were investigated. The pollen grains collected at 05:00-06:00 hrs had the highest viability, and the viabilities of “Jinsenianhua” and “Qinhuaihuadeng” were 20.6 and 15.7%, respectively. At 4 h after artificial pollination, the number of pollen grains germinating on each stigma reached a peak: 63.0 and 17.2 per stigma in “Jinsenianhua” × “Qinhuaihuadeng” and “Qinhuaihuadeng” × “Jinsenianhua”, respectively. At 1 d after artificial pollination, the percentages of normal embryos in the two crosses were 55.0 and 21.9%, respectively; however, at 11 d after pollination, the corresponding percentages were 20.8 and 11.2%. Seed sets of the two crosses were 17.9 and 8.0%, respectively. The results suggested that low pistil receptivity and embryo abortion caused low seed set in “Qinhuaihuadeng” × “Jinsenianhua”, whereas low fecundity of “Jinsenianhua” × “Qinhuaihuadeng” was mainly attributable to embryo abortion
3-Mesityl-2-oxo-1-oxaspiro[4.4]non-3-en-4-yl 4-chlorobenzoate
The title compound, C24H23ClO4, is a potent insecticide and miticide. The five-membered cyclopentane ring displays an envelope conformation with the atom at the flap position 0.611 (2) Å out of the mean plane formed by the other four atoms. The furan ring makes dihedral angles of 71.3 (2) and 81.9 (2)°, respectively, with the 2,4,6-trimethylphenyl and 4-chlorophenyl rings. The dihedral angle between the two benzene rings is 76.6 (1)°. In the crystal, molecules are linked through weak intermolecular C—H⋯O hydrogen bonds, forming chains running along the c axis
(1R,3S,5R,6S)-6-Hydroxy-3-tosyloxytropan-8-ium chloride
The title compound, C15H22NO4S+·Cl−, is a hydrolysis product of lesatropane [(1R,3S,5R,6S)-6-acetoxy-3-tosyloxytropane] hydrochloride, a potential antiglaucoma agent. As in lesatropane, the piperidine and pyrrolidine rings in the title compound adopt chair and envelope conformations, respectively. There are two molecules in the unit cell with similar conformations. The crystal structure is stabilized by intermolecular O—H⋯Cl and N—H⋯Cl hydrogen bonds
Decoupled advection-dispersion method for determining wall thickness of slurry trench cutoff walls
Low-permeability slurry trench cutoff walls are commonly constructed as barriers for containment of subsurface point-source pollution or as part of seepage-control systems on contaminated sites. A method to estimate wall thickness in slurry wall design is proposed based on decoupling the advective and dispersive components of contaminant fluxes through the wall. The relative error of the result obtained by the proposed method compared with that by an analytical solution was found to increase as the ratio of the specified breakthrough exit concentration (c*) to the source concentration (c0) increased. For c*/c0 of less than 0.1, which covers common practical situations, the relative error was not greater than 4% and was always conservative, indicating that the proposed method provides sufficient accuracy for design. For a given breakthrough criterion (i.e., c*/c0), the relative error was low for the scenarios having either a low or high column Peclet number, where either dispersion or advection dominates the contaminant migration, respectively, and the relative error was high for the scenario having an intermediate column Peclet number, in which case the coupling effect of advective and dispersive migrations is relatively high
Study on Extraction, Purification and Degradation Kinetics of Anthocyanins from Lycium ruthenicum
In this study, taking the amount of anthocyanin extraction as the main index, the extraction process of lyophilized Lycium ruthenicum anthocyanin was optimized by one-way and orthogonal tests, and the purification process of anthocyanin and its degradation kinetics were studied under these conditions, to explore the changes of the extraction amount of anthocyanin under different temperatures and pH. The results showed that the optimal conditions for the extraction process: The material-liquid ratio was 1:25 (g:mL), the ethanol concentration was 60%, the pH was 4, and the extraction time was 2 h, which resulted in a purification rate of 90.02%. The amount of anthocyanosides extracted under these conditions amounted to 36.507±0.325 mg/g. In addition, the study showed that AB-8 macroporous resin was the most effective in purifying anthocyanin from Lycium ruthenicum, and it had the best effect on the adsorption and desorption of anthocyanin. The optimal conditions were: The concentration of the sample solution was 200 mg/100 g, the concentration of desorbed ethanol was 80%, the flow rate of the sample was 2 mL/min, the flow rate of elution was 2 mL/min, and the volume of the sample was 5 BV. The results of the degradation kinetics study showed that the degradation rate of anthocyanin increased with increasing temperature and the half-life decreased at the same pH. Moreover, anthocyanosides were more stable in acidic environment and easily degraded in alkaline environment, and the stability of anthocyanosides was the best with the maximum of t1/2 of 38.5 h and the maximum of Ea of 41.89 kJ/mol at pH3 and 50 ℃. Therefore, the content of Lycium ruthenicum anthocyanin is closely related to its extraction, purification and stability of process conditions, this study provides technical support for the extraction of wolfberry anthocyanin and the development of beverages
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Japanese Encephalitis Accompanied by Cerebral Venous Sinus Thrombosis: a Case Report
Background: Cerebral venous sinus thrombosis (CVST) is a relatively rare cerebrovascular condition which accounts for 0.5% of all strokes. Risk of CVST has been documented in patients with numerous conditions including central nervous system infections, however, Japanese encephalitis (JE, epidemic encephalitis type B) with CVST has not been reported previously. Case Presentation: Here, we present a case of JE with CVST in a 17-year-old man. On admission, the patient was initially diagnosed as intracranial infection, and soon after, brain magnetic resonance (MR) imaging (MRI) and MR Venography (MRV) confirmed the diagnosis of CVST. Moreover, the blood JE-specific IgM antibody which proved weakly positive at first, turned positive one week later. Consequently, our patient was diagnosed as CVST accompanied by JE. Anticoagulant and anti-infective therapy were initiated, which eventually lead to gradual recovery of the patient. Conclusions: To our knowledge, this is the first case report of CVST associated with JE. MRI and MRV represent a prime method for the diagnosis of CVST, while the positivity of JE virus IgM antibody, especially increased antibody levels within a short period, is of great significance to diagnose JE. The early diagnosis and timely treatment of this potentially lethal condition would improve its prognosis significantly
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