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Five new ent-abietane diterpenoids (1–5), along with nine known analogues (6–14), were isolated from the roots of Euphorbia fischeriana. Their structures and absolute configurations were determined by the analysis of extensive spectroscopic data (UV, IR, HRESIMS, NMR) and the comparison of the experimental and calculated electronic circular dichroism (ECD). Among the isolates, it's notable that the ent-abietane diterpenoids bearing an additional five-membered lactone ring might be derived from the proposed precursors of fischeriabietane B (2) and C (3), and their plausible biosynthetic relationship was detailed discussed. All the isolates were evaluated for cytotoxicity against three human cancer cell lines (Panc-28, Bel-7402, and HT-29), 2 and 3 exhibited moderate cytotoxicity.

A free-standing, flexible, and semi-transparent MoO3 nanopaper was fabricated using ultralong MoO3 nanobelts (length ∼ 200 μm; width 200–400 nm), and its gas-sensing characteristics were investigated. The sensor exhibited high responses (resistance ratio) of 49 to 5 parts per million (ppm) hydrogen sulfide (H2S) at 250 °C and 121 to 5 ppm trimethylamine (TMA) at 325 °C with excellent gas selectivity, demonstrating its dual function for gas detection. Moreover, the sensor showed promising potential for the all-in-one detection of three representative offensive odors (TMA, H2S, and NH3) simply by tuning of the sensing temperature. This particular performance is attributed to the high chemical affinity of MoO3 to H2S and the acid–base interaction between basic TMA/NH3 and acidic MoO3. The mechanism underlying the control of gas selectivity by modulating the sensor temperature was investigated by Diffuse Reflectance Infrared Fourier Transform (DRIFT) measurements.

Lotus pollens were used as templates to prepare WO3 microspheres; the intriguing structural features of the pollens, e.g. hollow sphere with highly porous double shells, were perfectly inherited by the WO3 microspheres. The hierarchically porous structure of the WO3 microspheres was ideal for gas sensing. The WO3 microsphere-based sensor exhibited a high sensitivity (S = 46.2) to 100 ppm NO gas with a pretty fast response and recovery speed (62 s/223 s) at 200 °C. Compared with NO sensors reported in the literature so far, the WO3 microsphere-based sensor has among the highest sensitivity and fastest response/recovery.

Monodisperse erythrocyte-sized and acid-soluble chitosan microspheres are successfully prepared by an electrospraying method for the first time. Effects of the physical properties of the polymer solution and the condition parameters of the electrospraying process on the size and size distribution of the chitosan microspheres are systematically studied, to optimize the conditions for preparation of chitosan microspheres with our specific requirements. The microsphere size is mainly controlled by the viscosity of the spray liquid, and the microsphere monodispersity mainly depends on the electric conductivity of the spray liquid, the flow rate and the needle size. Under the optimized conditions, monodisperse chitosan microspheres with an average diameter of 6.4 μm, which is similar to the erythrocyte size, are prepared with a narrow size distribution (CV < 3%). Due to the use of terephthalaldehyde as cross-linker via formation of Schiff base bonds, the prepared chitosan microspheres can maintain structural integrity and show green fluorescence in a neutral medium, but display rapid acid-triggered decomposition. The prepared erythrocyte-sized and acid-soluble chitosan microspheres are highly attractive as promising substitutes of blood samples for calibration of hematology analyzers and flow cytometers.