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A novel silver-based dihydric alcohol extractant was substituted for ionic liquids to enrich methyl linolenate (C18-3) from tallow seed oil methyl ester in this study. The interactions among dihydric alcohol, Ag(I) and C18-3 were explored by FT-IR spectroscopy. The effects of dihydric alcohol structure, carrier Ag(I) concentration, temperature and initial feed concentration on extraction yield and selectivity were reported. The good extraction performance was achieved by 1,4-butanediol containing AgBF4. The complexation of Ag(I) with C18-3 was dominant in extraction operation rather than physical partition. Furthermore, a multi-step reverse extraction method was proposed to obtain C18-3 product and regenerate the extractant. 1-Hexene as the stripping phase can facilitate C18-3 reverse extraction. The content of C18-3 in the product was up to 93.36%, and the yield was 73.76%. This work opened a new route for the utilization of the dihydric alcohol properties to manipulate the carrier efficiency for extracting unsaturated fatty acid methyl esters at a lower cost.

Methyl linolenate (C18-3) is a type of unsaturated fatty acid methyl ester with high biological activity. Membrane separation of C18-3 from tallow seed oil methyl ester by supported ionic liquids membranes (SILM) containing carrier Ag+ was successfully achieved in this study. The interaction between Ag+ and C18-3 was explored by density functional theory (DFT). High selectivity to C18-3 was mainly due to the π/inverse π complexation interactions between Ag+ and C=C bonds. The effects of ionic liquid structure, carrier Ag+ concentration, adjacent phase flow rates and membrane pore size on permeability and selectivity to C18-3 were examined. The existence of 1-hexene in the stripping phase and carrier Ag+ can facilitate C18-3 transport. Good separation performance was achieved by the 0.45 μm nylon membrane impregnated with ionic liquid [BMIm]BF4 containing AgBF4. C18-3 was enriched from 16.7% in the feed phase to higher than 75% in the product. Moreover, adding a hydrophobic PVDF protective membrane to form a composite membrane was an effective method to increase the SILM stability and membrane lifetime by about twice compared with a single nylon membrane.

An innovative ball-mill reactor was designed and made to produce dimer acid continuously. Mixing and polymerization in the constructed reactor were intensified by the rotation of the cylinder and mechanical actions of small beads. A total of 3 baffles were set up to enhance radial turbulence, and 10 clapboards were sequentially installed to separate the whole reactor into 11 small reactors in series in order to make it close to a plug-flow reactor. The relationship between reaction performance and the inner components (baffles and clapboards), ball-milling medium, rotating speed, wall temperature and residence time were investigated. The crude product containing 50.6% dimer acid was obtained under the optimal conditions (zirconia beads as ball-milling medium, wall temperature 300 °C, residence time 2.16 h, rotating speed 20 rpm). Ferric and nickel ion from the reactor and the uneven residence time distribution resulted in low dimer acid production yield.

Methyl linolenate was separated from its analogues by a new extraction system constructed by solvent, imidazolium based ionic liquids and cuprous salt. Firstly, the effect of ionic liquid on the dissolution of CuCl in acetonitrile, N,N-dimethylformamide (DMF), methanol and water was evaluated by visual observation. [C4Mim][Cl] can improve the dissolution of CuCl in acetonitrile. Then, for the new system as acetonitrile-ILs-CuCl, extraction equilibrium, distribution ratio and selectivity of methyl linolenate and its analogues were determined by gas chromatography analysis and the mass balance. The extraction time, IL structures and CuCl concentrations were investigated. Distribution ratio decreased slightly, but selectivity increased significantly with the addition of CuCl, [C4Mim][Cl] or [C4Vim][NTF2] into acetonitrile. [C4Vim][NTF2] had higher selectivity than [C4Mim][Cl]. But the selectivity of the system combining CuCl with [C4Vim][NTF2] was much lower than with [C4Mim][Cl]. For the CuCl-[C4Mim][Cl]-acetonitrile, the extraction efficiency was better than CuCl-acetonitrile, increasing Cu+ concentration effectively improved the separation selectivity when ratio of CuCl/[C4Mim][Cl] was less than 1. Compared with previous aqueous AgNO3 extractions, the method of using CuCl is a much cheaper and practical way to enrich unsaturated fatty acid.

Supported liquid membranes show great potential in the efficient separation of methyl linolenate from its analogues, but there still remain some critical challenges to further this technology towards larger application because of the slow transmembrane transport and poor stability of liquid membrane. Herein, 1,2-butanediol (1,2-BDO) with good solubility for AgBF4 substitutes for ionic liquid as membrane solvent, and fabric reinforced hollow fiber composite membrane (PR-HFM) with higher mechanical strength and interfacial area replaces plate membrane as base support. A new supported liquid membrane has been prepared by coating the 1,2-BDO solution dissolving AgBF4 on the surface of PR-HFM and embedding the solution into the micro-pores of PR-HFM by repeated pull with vacuum and push with N2. The as-prepared liquid membranes exhibit good separation performance and stability. It can be safely and steadily used to treat the feed with fatty acid methyl esters (FAMEs) concentration lower than 150 mg/mL at the velocity of less than 0.22 m/s. Within 24 h continuous operation, methyl linolenate (C18-3) can pass steadily through the liquid membrane at the mean permeability larger than 3.13 × 10−7 m/s, the C18-3 product with the purity larger than 82% and the selectivity of C18-3 over C18-2 (SC18-3/C18-2) larger than 6.63 can be obtained steadily.

Oleaginous biomass conversion to liquid hydrocarbon biofuels has emerged as an effective solution to the energy crisis and environmental problems. In this process, the removal of oxygenated compounds will directly affect the effectiveness of subsequent biofuel applications. Herein, deoxygenation of oleic acid by catalytic cracking was conducted using five various elements (La, Ni, P, Zr and Ce) modified Al-MCM-41. The related characterizations were carried out for these catalysts, including N2 physisorption, XRD, XPS, pyridine-FTIR and NH3-TPD techniques. The results showed the mesoporous structure of Al-MCM-41 was maintained after different modifications, and these catalysts greatly improved the hydrocarbons content and physiochemical properties of biofuels. The modified catalysts tended to facilitate the decarbonylation pathway and showed high selectivity to alkane and aromatic hydrocarbons. Besides, La/Al-MCM-41 presented excellent anti-coking activity. Ni/Al-MCM-41 showed both high dehydrogenation and deoxygenation activities. The Zr modification and Ce modification had a promotion effect in the deoxidizing activity of the catalyst, owing to the formation of oxophilic metal oxides. Noteworthily, P/Al-MCM-41 displayed the best deoxidizing performance due to its high Bronsted acidity, which caused the highest hydrocarbons content (82.30 %) and the lowest fatty acids content (around 0 %) of the biofuel. Moreover, the resulting biofuel had not only low oxygen content (3.88 wt.%) and acid value (5.47 mgKOH g−1) but also a high calorific value (44.50 MJ kg−1), which could be processed into green diesel. Hence, the catalytic cracking of fatty acid over P/Al-MCM-41 has excellent potential to produce high-quality renewable fuels.

Montmorillonite (MMT) is widely used as the catalyst in the commercial production of dimeric fatty acids (DAs). However, the dimerization activity of MMTs from different mineral sources is usually different, leading to unstable yield of DAs. In order to obtain a high and stable yield of DAs, the relationship between the dimerization activity and characteristics of MMT should be clarified. The characteristics of seven MMTs from different mineral sources, including the acidity (the type, strength, and amount of the acid sites), composition (interlayer cations, Si/Al ratio, water content, pH), and structure (basal spacing) are determined and correlated with their dimerization activity. Additionally, the relationship between dimerization activity and characteristics of MMT is quantified by nonlinear‐regression. It is found that the dimerization activity of MMT is mainly influenced by its Bronsted acidity and basal spacing. Stable DA yield of around 70% on MMT is obtained at the amount of weak Bronsted acid sites of more than 0.20 mmol g⁻¹ and basal spacing of larger than 1.50 nm. Additionally, it is found that acid treatment is an effective method to adjust the Bronsted acidity and basal spacing of MMT. Practical Applications: The positive effect of Bronsted acid sites amount and basal spacing on the activity of MMT has practical value on the selection of highly efficient MMT catalyst for DA production. In addition, some MMT with poor activity can be activated by the acid treatment method mentioned in the paper.

A novel amphiphilic derivative of chitosan, namely, a linoleic acid-g-quaternary chitosan (LA-g-QC), was designed and synthesized as low toxic material for biomedical applications in this study. The chemical structure of LA-g-QC was characterized by Fourier transform infrared spectroscopy (FTIR),1H nuclear magnetic resonance (1H-NMR), and elemental analysis. LA-g-QC could form nanosized micelles with self-assembly, which was confirmed by the results of critical micelle concentration (CMC) via fluorescence spectroscopy. The average size of LA-g-QC was 140 nm and its zeta potential was approximately +35.50 mV. CMC value was 31.00 mg/mL. Furthermore, LA-g-QC micelles, at final concentrations between 0.94 μg/mL and 30 μg/mL, did not inhibit the proliferation of HepG2 or SMMC 7721 cell lines. Taken together, LA-g-QC has low cytotoxicity and high potential for the preparation of novel drug-delivery micelles.

An accurate and validated liquid chromatography method and a triple quadrupole mass spectrometry method were developed and validated to simultaneously evaluate the cytochrome P450 (CYP) enzymes in vivo using the co-administration of these probes. Phenacetin, losartan, metoprolol and midazolam were used as the probe substrates for rat CYP1A2, CYP2C11, CYP2D4 and CYP3A1 enzymes, respectively. The purpose of the study was to investigate the effect of apatinib on these cytochrome P450 enzymes in vivo with co-administration of these probes. Plasma samples were prepared by precipitating protein with acetonitrile. The analytes were separated using a reversed-phase BEH C18 column (2.1mm×100mm, 1.7μm, Waters, USA) maintained at 40°C. The mobile phase consisted of acetonitrile and water (containing 0.1% formic acid) with a gradient elution pumped at a flow rate of 0.4mL/min. The analytes were detected with positive electrospray ionization in multiple reaction monitoring (MRM) mode for target fragment ions m/z 180.05→109.94 for phenacetin, m/z 423.1→207.2 for losartan, m/z 268.12→115.8 for metoprolol, m/z 326.02→290.99 for midazolam and m/z 285.1→193.1 for diazepam (IS). Good linearity was achieved to quantify the concentration ranges of 10-2000ng/mL for phenacetin, 10-1000ng/mL for losartan, 10-1000ng/mL for metoprolol and 1-100ng/mL for midazolam in rat plasma. The mean recoveries of phenacetin, losartan, midazolam and metoprolol from the plasma exceeded 77.07%. The intra-run and inter-run assay precisions were both less than 8.9%. This method was successfully applied to evaluate the effects of apatinib on the cytochrome P450 enzymes in rats.

Lithium–sulfur (Li–S) battery is one of the most attractive candidates for the next-generation energy storage system. However, the intrinsic insulating nature of sulfur and the notorious polysulfide shuttle are the major obstacles, which hinder the commercial application of Li–S battery. Confining sulfur into conductive porous carbon matrices with designed polarized surfaces is regarded as a promising and effective strategy to overcome above issues. Herein, we propose to use microalgaes (Schizochytrium sp.) as low-cost, renewable carbon/nitrogen precursors and biological templates to synthesize N-doped porous carbon microspheres (NPCMs). These rational designed NPCMs can not only render the sulfur-loaded NPCMs (NPCSMs) composites with high electronic conductivity and sulfur content, but also greatly suppress the diffusion of polysulfides by strongly physical and chemical adsorptions. As a result, NPCSMs cathode demonstrates a superior reversible capacity (1030.7 mA h g–1) and remarkable capacity retention...

The effects of pulse ultrasound with different pulse parameters on the breakthrough curves of Geniposide on Resin 1300 were studied. The mass transfer model describing the adsorption process was constructed. Adsorption capability and the overall mass-transfer coefficient were obtained by fitting the constructed mass-transfer model and the experimental data. The effects of pulse ultrasound on adsorption of Geniposide on Resin1300 in a fixed bed were studied and compared. Amount of Geniposide adsorbed on Resin 1300 in the presence of ultrasound is lower than that in the absence of ultrasound, but the mass-transfer rate with ultrasonic irradiation is higher than that without ultrasound. Furthermore, mass transfer rate is enhanced by pulse modulation. In the conditions studied, the adsorption equilibrium constant decreases with increasing ultrasonic power, while the overall mass-transfer coefficient increases. With increasing pulse duty ratio, adsorption equilibrium constant decreases initially, reaches a minimum when pulse duty ratio is 0.5, and then increases. On the contrary, the overall mass-transfer coefficient increases initially and reaches a maximum when pulse ratio is 0.5, and then decreases. Effects of pulse period on adsorption equilibrium and mass transfer rate reached the peak at pulse period of 28.6 ms.

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. Angiogenesis is reported to play a pivotal role in the occurrence, development and metastasis of HCC. The renin-angiotensin system (RAS) is involved in the regulation of angiogenesis. Here, based on the analysis of HCC datasets from Gene Expression Omnibus (GEO) database and The Cancer Genome Atlas (TCGA), we found that there was a negative correlation between the mRNA levels of angiotensin converting enzyme 2 (ACE2) and CD34. To explore the association of RAS with the progression from fibrosis to cirrhosis to HCC, liver specimens and serum samples were collected from patients with hepatic fibrosis, cirrhosis and HCC. Relative hepatic mRNA levels of CD34 and ACE2 were determined by real-time PCR, and the serum concentrations of Angiotensin II (Ang II), Ang (1-7) and vascular endothelial growth factor (VEGF) were detected by ELISA. We found that ACE2 mRNA was gradually decreased, while CD34 mRNA was progressively increased with the increasing grade of disease severity. Concentrations of Ang II, Ang (1-7) and VEGF were higher in the sera of patients than in that of healthy volunteers. These proteins' concentrations were also progressively increased with the increasing grade of disease severity. Moreover, a positive correlation was found between VEGF and Ang II or Ang (1-7), while negative correlation was observed between mRNA levels of CD34 and ACE2. More importantly, patients with higher level of ACE2 expression had longer survival time than those with lower level of ACE2 expression. Taken together, our data suggests that the low expression of ACE2 may be a useful indicator of poor prognosis in HCC. The RAS may have a role in the progression of HCC.

A novel fluorescence detection method for phosphoproteins in 1-D and 2-D SDS-PAGE by using purpurin is developed in this study. Phosphoproteins as low as 4–8 ng could be specifically detected by purpurin within 60 min, and the detection limit is similar to or better than that of Pro-Q Diamond staining. Only 2 steps (staining and destaining) are needed for purpurin staining without requiring excessive fixing and washing steps, and for single use, $0.8 is enough for purpurin staining. By comprehensively comparing with Pro-Q Diamond staining, it is concluded that purpurin staining is a simple, rapid and low-cost staining method for a broad application to the research of phosphoproteins.

For analysis of nitration modification of α oxoglutarate dehydrogenase (α-OGDH) induced by diabetes, a targeted proteomics strategy was developed through the use of Skyline. All peptides containing Y and W of the target proteins were nitrated in silico and output to produce parallel reaction monitoring (PRM) or SRM method for nitration analysis. A nitrated casein mixture was used as standard protein to assess the feasibility of this method. The results demonstrated the availability of this strategy for nitration identification, and subsequently this method was used to analyze the nitration of α-OGDH from myocardial tissue extracts of diabetic mouse. The PRM method was primarily generated by Skyline for identification of the actual nitrated peptides from all possible nitrated peptides of α-OGDH due to the complexity of α-OGDH. The PRM-based data were analyzed by SEQUEST, and transitions of the identified nitrated peptides were used to develop an SRM method for relative quantitation of nitration degree. The nitration degree of α-OGDH for diabetic mouse is higher than that for control mouse, indicating that α-OGDH of the diabetic mouse suffered from more intense oxidative damage. We believe that this approach for obtaining information regarding nitration will facilitate the study of other PTMs in complex mixtures.

The effects of trace elements on the lipid productivity and fatty acid composition ofNannochloropis oculata (N. oculata)were studied. The results showed that trace elements had a strong influence on not only the lipid productivity but also the fatty acid composition. The addition of Fe3+, Zn2+, Mn2+, Mo6+, and EDTA and the deletion of Cu2+and Co2+can increase the lipid productivity. The optimum concentrations of the trace elements in the culture medium are 6 times of Fe3+and EDTA, the same concentration of Zn2+, Mn2+, and Mo6+as the control group, but the optimum medium has no Cu2+or Co2+. Fe3+, Zn2+, Mn2+, Mo6+, and EDTA are indispensable during the EPA formation ofN. oculata. The addition of Fe3+, Zn2+, Mn2+, Mo6+, and EDTA can strongly increase the content of EPA in the lipid ofN. oculata, but the concentration of the trace elements had little influence on the level of EPA.

Bi-functional catalysts consisting of platinum on aluminosilicate MCM-41 materials with Si/Al ratios between 10 and 30 were prepared via direct mixed-gel synthesis. The catalysts were tested in the hydrocracking of bio-alkanes, produced from biodiesel hydrodeoxygenation and composed of n-hexadecane and n-octadecane, for the production of bio-jet fuel. The effects of temperature, pressure, weight hourly space velocity (WHSV), and H2/n-paraffin weight ratio on bio-alkanes conversion and product distribution were examined. The conversion was found to be dependent on the acid strength of the catalyst supports which were proportional to the Al content. However, the catalyst selectivity decreased with the increasing Al content. The optimal Si/Al ratio, temperature, pressure, WHSV, and H2/n-paraffin weight ratio were determined to be 20, 330 °C, 2 MPa, 1 h−1, and 0.20, respectively. Under these conditions, the bio-alkanes conversion and kerosene/gasoline ratio in the product reached 65.62% and 1.96, respectively.