Ultra‐long‐chain amidobetaine surfactants have become one of the hot topics recently, but the influence of the hydrophilic head group on the aggregation behaviors and the correlation between surface activities and thickening ability have been less documented. In this work, comparative studies on the effect of the hydrophilic group on Krafft temperature (TK), surface activities and rheological behaviors of erucyl amidobetaines with sulfonate, hydroxyl‐sulfonate or carboxylate were examined. Compared to the sulfobetaines, the carboxybetaine is more water‐soluble; the addition of an hydroxyl group onto the head group of sulfobetaine increases water‐solubility leading to a lower TK. Unexpectedly, the nature of the head groups has little effect on the critical micelle concentration and thickening ability of these surfactants. The packing parameter prediction verifies the formation of wormlike micelles which accounts for the strong thickening ability of the surfactant aqueous solutions.

A “worm”-containing viscoelastic fluid based on single unsaturated C22-tailed amine oxide surfactant shows pH-controlled thermo-thickening behaviour.

A series of organoselenium compounds based on the hybridization of nonsteroidal antiinflammatory drugs (NSAIDs) scaffolds and Se functionalities (-SeCN and -SeCF 3 ) were synthesized and characterized, and evaluated against four types of cancer cell lines, SW480 (human colon adenocarcinoma cells), HeLa (human cervical cancer cells), A549 (human lung carcinoma cells), MCF-7 (human breast adenocarcinoma cells). Interestingly, most of the investigated compounds showed active in reducing the viability of different cancer cell lines. The most active compound 3h showed IC 50 values lower than 20 μM against the four cancer cell lines, particularly to SW480 and MCF-7 with IC 50 values of 4.9 and 3.4 μM, respectively. Furthermore, NSAIDs-SeCN derivatives (2h and 2i) and NSAIDs-SeCF 3 derivatives (3h and 3i) were selected to investigate their ability to induce apoptosis in MCF-7 cells via modulation the expression of anti-apoptotic Bcl-2 protein, pro-inflammatory cytokines (IL-2) and proapoptotic caspase-3 protein. Moreover, the redox properties of the synthesized organoselenium candidates were conducted by 2, 2-didiphenyl-1-picrylhydrazyl (DPPH), bleomycin dependent DNA damage and glutathione peroxidase (GPx)-like assays. Taken together, these NSAIDs-Se candidates could provide promising new lead derivatives for further potential anticancer drug development.

Gas mixing in a tall narrow fluidized bed operated in the slugging fluidization regime is simulated with the aid of computational fluid dynamics. In the first part, a parametric study is conducted to investigate the influence of various parameters on the gas mixing. Among the parameters studied, the specularity coefficient for the partialslip solid-phase wall boundary condition had the most significant effect on gas mixing. It was found that the solid-phase wall boundary condition needs to be specified with great care when gas mixing is modeled, with free slip, partial slip and no-slip wall boundary conditions giving substantial differences in the extent of gas back mixing. Axial and radial tracer concentration profiles for different operating conditions are generally in good agreement with experimental data from the literature. Detailed analyses of tracer back mixing are carried out in the second part. Two parameters, the tracer backflow fraction and overall gas backflow fraction, in addition to axial profiles of cross-sectional averaged tracer concentrations, are evaluated for different flow conditions. Qualitative trends are consistent with reported experimental findings.

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Polyporus umbellatus is a widely used diuretic herbal medicine. In this study, a high-performance liquid chromatography coupled with atmospheric pressure chemical ionization-mass spectrometric detection (HPLC-APCI-MS) method was developed for qualitative and quantitative analysis of steroids, as well as for the quality control of Polyporus umbellatus. The selectivity, reproducibility and sensitivity were compared with HPLC with photodiode array detection and evaporative light scattering detection (ELSD). Selective ion monitoring in positive mode was used for qualitative and quantitative analysis of eight major components and beta-ecdysterone was used as the internal standard. Limits of detection and quantification fell in the ranges 7-21 and 18-63 ng/mL for the eight analytes with an injection of 10 microL samples, and all calibration curves showed good linear regression (r(2) > 0.9919) within the test range. The quantitative results demonstrated that samples from different localities showed different qualities. Advantages, in comparison with conventional HPLC-diode array detection and HPLC-ELSD, are that reliable identification of target compounds could be achieved by accurate mass measurements along with characteristic retention time, and the great enhancement in selectivity and sensitivity allows identification and quantification of low levels of constituents in complex Polyporus umbellatus matrixes.

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