Effects of Hydraulic Conditions on Effluent Quality, Flux Behavior, and Energy Consumption in a Shear-Enhanced Membrane Filtration Using Box-Behnken Response Surface Methodology

A systematic study has been carried out to get insight into the effect of hydraulic conditions (feed flow rate (<i>Q</i>), transmembrane pressure (TMP), and rotating speed (<i>N</i>)) on the treatment of dairy wastewater with shear-enhanced membrane flirtation using Box-Behnken response surface methodology (BBRSM). Performances of three types of ultrafiltration (UF) membrane (UH005P, UH030P, and PES050) were compared to choose the optimal membrane. A 1.5 h test was conducted on the analysis of kinetics of permeate flux decline under various hydraulic conditions. With the help of the BBRSM method, the influence and interactions of three hydraulic factors were investigated and regression models were built, while data on effluent quality, flux behavior, and energy consumption as the response values were collected. The results showed that TMP, rotating speed, and their interaction effects could improve significantly effluent quality and flux behavior, reduce several irreversible and total filtration resistancess and greatly decrease energy consumption. The optimal hydraulic conditions obtained by BBRSM were as follows: <i>Q</i> = 75.81 L/h, TMP = 7 bar, and <i>N</i> = 2250 rpm. Under these conditions, the best effluent quality, optimal flux behavior, and minimal energy consumption have been observed

Effect of Fluorinated Substituents on Solubility and Dielectric Properties of the Liquid Crystalline Poly(ester imides)

With the rapid advancement of 5G communication technology, much attention has been paid on high-performance polymers with a low dielectric constant (Dk), a low dielectric loss (Df) and good processability. In order to further research and improve dielectric properties of the liquid crystalline poly(ester imide)s (LCPEIs), four imide dicarboxylic acids (IAs) with fluorinated groups are designed and synthesized. They are then copolymerized with 1,3-phthalic acid (IPA), p-hydroxybenzoic acid (HBA), and bisphenol monomers via solution polycondensation to obtain fluorinated PEIs, whose fluorine content, position of the fluorinated group, and LC behavior are tunable by using different IAs and bisphenol monomers. These PEIs with the highest Tg of 238 °C are soluble in general organic solvents, such as m-cresol, N-methyl-2-pyrrolidone (NMP), chloroform, and so on. PEI-6F25AF exhibits the lowest Dk of 2.60, while LCPEI-6FD shows the lowest Df of 0.0053 at 10 GHz. It is found that high fluorine content and large pendent group can reduce the Dk, while the fluorinated group grafted close to the nitrogen atom and the LC rigid rod-like conformation lead to low Df. We devoutly expect that this research offers some reference for structure design of LCPEIs with both low Dk and Df at high frequency

The Bayesian age-depth model of the Xiaozhongdian Basin section.

<p>The Bayesian age-depth model of the Xiaozhongdian Basin section.</p

Variation of oxide and element contents in the Xiaozhongdian Basin section.

<p>Variation of oxide and element contents in the Xiaozhongdian Basin section.</p

Comparison of CIA for Xiaozhongdian Basin sediments with CIAs for rock and minerals (Based on [33, 34]).

<p>Comparison of CIA for Xiaozhongdian Basin sediments with CIAs for rock and minerals (Based on [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0168928#pone.0168928.ref033" target="_blank">33</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0168928#pone.0168928.ref034" target="_blank">34</a>]).</p

Radiocarbon dating of the lake sediment of Xiaozhongdian Basin and the age model.

<p>Radiocarbon dating of the lake sediment of Xiaozhongdian Basin and the age model.</p

The correlation among the TiO₂ contents, CIA, ICV and (CaO+K₂O+Na₂O)/Al₂O₃.

<p>The correlation among the TiO₂ contents, CIA, ICV and (CaO+K₂O+Na₂O)/Al₂O₃.</p

Fabrication of Novel Avermectin Nanoemulsion Using a Polyurethane Emulsifier with Cleavable Disulfide Bonds

In this study, a polyurethane emulsifer with various functional groups was prepared from isophorone diisocyanate, avermectin, 2,2-dimethylol propionic acid, and bis­(2-hydroxyethyl) disulfide. The chemical structure of the polymer was confirmed by Fourier transform infrared spectroscopy, proton nuclear magnetic resonance, and element analysis. The polymer exhibited adequate emulsification ability for avermectin after neutralization with triethylamine. A satisfaying nanoemulsion was obtained, in which avermectin was encapsulated in nanoparticles with 50 wt % drug loading, low organic solvent content, and high stability under dilution and centrifuging treatment in addition to low surface tension, high affinity to crop leaf, and improved avermectin photostability. The resulting nanoparticles showed degradability in the presence of dl-dithiothreitol or inside the insect as a result of the disulfide bonds, promoting the release of avermectin. As a result, the avermectin nanoparticles showed higher insecticidal ability compared to both the avermectin nanoparticles without a disulfide group and the avermectin emulsifiable concentrate

The characteristics of geochemical proxie, sporopollen in the Xiaozhongdian Basin and δ¹⁸O of Hulu Cave stalagmites [39] (the abundance data for <i>Cupressaceae</i> and <i>Picea asperata Mast</i> is from [19]).

<p>The characteristics of geochemical proxie, sporopollen in the Xiaozhongdian Basin and δ¹⁸O of Hulu Cave stalagmites [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0168928#pone.0168928.ref039" target="_blank">39</a>] (the abundance data for <i>Cupressaceae</i> and <i>Picea asperata Mast</i> is from [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0168928#pone.0168928.ref019" target="_blank">19</a>]).</p

The location and digital elevation model of the Xiaozhongdian Basin lacustrine deposits (the data come from http://srtm.csi.cgiar.org for open-source. The figure is similar but not identical to the original image of SRTM, and is therefore for illustrative purposes only.)

<p>The location and digital elevation model of the Xiaozhongdian Basin lacustrine deposits (the data come from <a href="http://srtm.csi.cgiar.org/" target="_blank">http://srtm.csi.cgiar.org</a> for open-source. The figure is similar but not identical to the original image of SRTM, and is therefore for illustrative purposes only.)</p