To break oil-in-water emulsions with an average oil droplet size of <2 μm, a series of hyperbranched polyglycerol (HPG)-based demulsifiersmethacrylated hyperbranched polyglycerol (HPG-MA)are synthesized successfully by controlling the ratio of HPG to glycidyl methacrylate (GMA). Dosage, temperature, settling time, and salinity are taken into account to evaluate the performance of these demulsifiers, respectively. The oil removal ratio with the addition of HPG-MA demulsifier can exceed 86% within 40 min to reach the equilibrium of demulsification, in comparison with ∼90 min for previously reported demulsifiers. Because of the specific branched structure, the demulsifier can multipointly adhere to the oil/water interface, and then shorten the time of adsorption and increase the rupture rate of oil droplets. The oil–water interfacial tensions with the demulsifier in the water phase are further measured to help comprehend the demulsification mechanism. The change of oil droplet size against time, which reflects flocculation and coalescence of oil droplets, is vividly monitored during the process of demulsification. The demulsification performance indicates that the novel HPG-MA demulsifier displays great promise in the petroleum industry.

One of the amidoamine-structured hyperbranched polymers is developed as an efficient macroinitiator to enhance the endothermic capacity of hydrocarbon fuels to meet the stringent cooling requirement of hypersonic aircrafts. Hyperbranched poly(amidoamine) (PAMAM) is treated with palmitoyl chloride to modify a lipophilic shell on the hydrophilic core, and the amphiphilic product, palmitoyl-hyperbranched poly(amidoamine) (PPAMAM), can be well-dissolved in hydrocarbon fuels. The long alkyl chains in PPAMAM break away from the core at about 200 °C, and the PAMAM core destructs around 400 °C. The high decomposition temperature of the core enables PPAMAM to be performed as a macroinitiator for hydrocarbon fuels. Thermal cracking of methylcyclohexane (MCH) from 600 to 720 °C with the addition of PPAMAM is carried out in an electrically heated tubular reactor under the pressure of 3.5 MPa. Significant improvements of the conversion, gas yield, and heat sink of MCH with PPAMAM are observed. The conversion of MCH is increased from 39.5 to 56.3 wt % at 690 °C, and the corresponding heat sink has been raised from 2.48 to 2.91 MJ/kg. Furthermore, PPAMAM with the optimum molecular weight is employed for the cracking of aviation kerosene. The heat sink is also improved significantly in comparison to that from the thermal cracking of bare kerosene, which confirms the effective application of PPAMAM in endothermic hydrocarbon fuels.

The demulsification of oil-in-water emulsions with microdroplets has drawn great attention as a result of their extreme stability and difficulty of separation. In this work, a series of palmitoyl-hyperbranched polyethylenimine (CHPEI) with a hyperbranched structure was developed to meet the requirement of the demulsification. The influential factors of the demulsifier concentration, sedimentation time, and temperature on demulsification were investigated to give a clear view of CHPEI-based demulsification. The results indicated that the oil removal efficiency reached 91% by adding 80 mg/L CHPEI with sedimentation time of 30 min and showed a short sedimentation time and low addition amount compared to traditional demulsifiers. Further, to better acquire the mechanism of demulsification, the oil–water interfacial tension of CHPEI demulsifiers in aqueous phase and the real-time size changes of oil droplets were both recorded. These properties make CHPEI a potential candidate as an efficient demulsifier for crude oil.

Oxygenated additives have been proved to improve the property of an aviation fuel, such as reducing pernicious emissions and adjusting physical properties, and an appropriate alcohol is usually a typical candidate. To understand the properties of high-energy-density hydrocarbon fuels with alcohol, densities (ρ) and viscosities (η) of ternary system, cyclopentanol + exo-tetrahydrodicyclopentadiene (JP-10) + 1,3dimethyladamantane (1,3-DMA), and their corresponding binary systems, have been determined over the whole composition range at different temperatures, T = (293.15− 333.15) K, and atmospheric pressure, p = 0.1 MPa. The excess molar volumes (V m E ) and the viscosity deviations (Δη) of the binary systems mixtures were calculated and fitted to the Redlich−Kister equation, while those of the ternary systems were calculated and fitted to four different semiempirical equations. The results show that the addition of cyclopentanol can lead to a little higher density and a lower viscosity, which are beneficial to the design and performance of hydrocarbon fuels.

Abstract. Breast cancer is one of the most lethal cancers affecting women worldwide and was estimated to account for ~30% of all new cancer diagnoses in women. Although available evidence has proved the tumor suppressor role of genistein in cancer, the underling mechanisms have remained to be fully elucidated. S-phase kinase-associated protein 2 (Skp2) has been revealed to critically enhance the pathogenesis of multiple human cancers. The present study determined whether genistein exerts its anti-tumor function by suppressing Skp2 in breast cancer cells. Genistein significantly inhibited the proliferation, invasion and migration of breast cancer cells. Furthermore, genistein treatment also induced marked apoptosis and a typical cell cycle arrest in G2/M phase. Mechanistically, genistein treatment was identified to cause a significant downregulation of Skp2. Two crucial tumor suppressors, p21 and p27, were upregulated in genistein-treated breast cancer cells. The present results revealed that genistein exerted its tumor suppressor effect at least partially via inhibition of Skp2 and promotion of its downstream targets p21 and p27. Therefore, inactivation of Skp2 by genistein may be a promising approach for breast cancer treatment.