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High performance liquid chromatography-mass spectrometry is one of the most commonly used strategies for lipid analysis. The development of versatile chromatographic stationary phases to meet the increasing demands for separation of complex lipids is very important. Styrene-maleic acid (SMA) copolymer is an amphiphilic polymer, which has been proven to have the ability to solubilize lipid molecules of various structures. In this study, styrene-maleic anhydride copolymer coated silica was first prepared by the thiol-ene click reaction. With L-cysteine hydrochloride or dodecanol as the post-modification reagents, Sil-SMA-amino acid and Sil-SMA-dodecanol stationary phase materials were further successfully fabricated via nucleophilic ring-opening reaction. The Fourier-transform infrared, thermogravimetric analysis, and elemental analysis results confirmed the two stationary phase materials were successfully prepared. Furthermore, both the Sil-SMA-dodecanol column and the Sil-SMA-amino acid column possessed reversed-phase/hydrophilic interaction/ion exchange mixed-mode retention mechanisms. The column efficiency of the Sil-SMA-derivatives columns reached 77,300 N/m. Based on the mixed-mode retention characteristics, the Sil-SMA-derivatives columns achieved both the lipid classes and species separation via a single column. The Sil-SMA-amino acid column was further successfully used to separate lipid extract from gastric cancer cell membrane. All these results demonstrated that the SMA-based stationary phase materials have a good potential for use in lipid separation.

ZnMgAl-LDHs were prepared by co-precipitation method and modified with starch to transform the structure for the adsorption property improvement. Samples were characterized by XRD, BET, SEM and FT-IR. Effect of starch soluble dosage, initial MO concentration and absorbent dosage on adsorption property of samples was studied. LDH samples modified by starch with starch versus Al3+ mole ratio of 0.0625 and calcinated at 450 °C for 5 h, exhibited higher crystallinity, higher surface area and more mesopores, which were beneficial to the adsorption process, the adsorption capacity on methyl orange (MO) reached 1555 mg/g. The kinetic data of adsorption were well fitted by the pseudo-second-order kinetic equation, while the isotherm data were well represented by the Langmuir equation. Starch doped method was a valid means to enhance adsorption performance.

Dielectric barrier discharge (DBD) non-thermal plasma was applied for ZnMgAl-LDHs modification to improve the adsorption property of methyl orange (MO). ZnMgAl-LDHs were prepared by co-precipitation method, and characterized via XRD, EDS, BET, SEM and FT-IR. Effects of plasma modification time, initial pH, initial MO concentration and adsorbent dosage on adsorption property of samples were investigated. The results showed that plasma modification led to the increase of specific surface area, pore volume and average pore size, as well as good dispersion. ZnMgAl-LDHs treated by combination of plasma modification for 30 min with calcination at 450 °C for 5 h exhibited high adsorption capacity of 1327 mg/g, much higher than without plasma modification. The equilibrium data for the adsorption of MO on adsorbents could be well fitted by the Pseudo-second-order equation and Langmuir equation. Plasma modification could be a potential and effective way for adsorption property improvement.

Vigorously developing new high performance liquid chromatography (HPLC) stationary phases to meet the versatile separation requirements is still an important issue in the field of analytical chemistry. Conjugated microporous polymers (CMPs) are a new type of three-dimensional network porous material with high specific surface area, good chemical stability and superhydrophobicity. Herein, we firstly report the synthesis and applications of CMPs@SiO2 material for HPLC stationary phase. The CMPs@SiO2 material can be in situ fabricated via Sonogashira coupling of 1,3,5-triethynylbenzene and 1,4-diiodobenzene on the surface of spherical silica. The morphology and physicochemical properties of the synthesized stationary phase material were investigated by a series of characterization methods. Due to the superhydrophobic nature of the CMPs@SiO2 material, the packed CMPs@SiO2 HPLC column displays ultrastrong chromatographic retention and can be used for separation of both hydrophobic and hydrophilic compounds with good selectivity. Significantly, CMPs@SiO2 column can be performed for separation with pure acetonitrile as the eluent. Thus, the new column was successfully exploited for monitor and analysis of the hydrolysis of silane coupling agents. Furthermore, based on its oleophilicity, this report firstly utilized the CMPs@SiO2 material to identify and analyze the quality of cooking oils through one-step enrichment and subsequent HPLC separation. We will further exploit to fabricate versatile CMPs-based stationary phases, highlighting their potential applications in different separation scopes.

Large quantity of fine Ti(C,N) particles, 15–30 nm in size, were observed in low carbon hot strips added to a small amount of Ti and produced by CSP process. The results showed that the precipitation of Ti(C,N) mostly took place during soaking and hot rolling, which is significantly different from that in the conventional production. These fine Ti carbonitride panicles could be very effective or. the austenite grain refinement by hindering grain growth of recrystallized austenite. Their precipitation behavior was discussed and compared with that of the steels produced in the conventional production.

In this study, microstructures of 1.9 mm hot strip steel produced by compact strip production (CSP) are investigated by using optical metallograph observation and electron back-scattered diffraction (EBSD) data to deduce the status of hot rolled austenite before phase transformation, because the evolution of hot rolled austenite is important to provide information for the microstructure refinement. The experimental results show that the finishing hot rolled microstructure is a mixture of recrystallized and deformed austenite, and the percentage of recrystallized austenite is greater than that of the deformed austenite. At last, microstructure evolution of austenite is modeled based on chemical compositions and techniques of producing 1.9 mm hot strip. The simulation results agree well with experimental data. Analysis shows that microstructure refinement, recrystallization and supercooling rate are the primary causes to fine microstructure.