Coal-Based Branched Vicinal Diol Ethoxylates Versus Guerbet Alcohol Ethoxylates: Role of Tertiary Hydroxyl Groups.

Branched surfactants exhibit a lower surface tension, excellent low defoaming performance, and better wetting ability compared with linear surfactants, making them promising for applications in industrial cleaning. In this study, 2-hexyl-1-decene (C8 olefin dimer), obtained from the dimerization of 1-octene, was used as the hydrophobe to synthesize branched nonionic surfactants via hydroxylation and ethoxylation. The hydroxylation of the C8 olefin dimer to synthesize 2-hexyldecane-1,2-diol (C8 BD) using H2O2 and HCOOH was investigated systematically. Under the optimal reaction conditions (H2O2/C8 olefin dimer molar ratio: 1.5, HCOOH/C8 olefin dimer molar ratio: 4.0, reaction time: 10 h, reaction temperature: 50 °C), the conversion of the C8 olefin dimer and selectivity toward C8 BD were found to reach 99.96 and 79.89%, respectively. Further, branched nonionic surfactants (C8 BDEn) were synthesized via ethoxylation of C8 BD with ethylene oxide and characterized using FTIR, LCMS, 1H NMR, and 13C NMR techniques. The presence of a tertiary hydroxyl group in C8 BD increases the reactivity of the primary hydroxyl group, leading to a narrower range of products and lower residual substrate content. The physicochemical properties and surface properties of C8 BDEn with different degrees of ethoxylation at various concentrations were investigated and compared with those of commercially available Guerbet alcohol polyoxyethylene ethers (C8 GAEO9 and C6 GAEO9). The results show that, compared with C8 GAEO9 and C6 GAEO9, C8 BDE6 displayed a higher surface activity with a lower equilibrium surface tension (27.14 mN·m-1), superior wettability with a smaller contact angle (39.2°), better emulsification performance with a longer emulsification time of 548 s, and excellent foaming properties (initial foam volume of 11.6 mL). This strategy of utilizing coal-based α-olefins for the synthesis of branched nonionic surfactants presents a route to prepare value-added fine chemicals from coal-based resources.

Integration of a Cu2O/ZnO heterojunction and Ag@SiO2 into a photoanode for enhanced solar water oxidation.

Photoelectrochemical water splitting (PEC-WS) has attracted considerable attention owing to its low energy consumption and sustainable nature. Constructing semiconductor heterojunctions with controllable band structure can effectively facilitate photogenerated carrier separation. In this study, a FTO/ZnO/Cu2O/Ag@SiO2 photoanode with a Cu2O/ZnO p-n heterojunction and Ag@SiO2 nanoparticles is constructed to investigate its PEC-WS performance. Compared with a bare ZnO photoanode, the photocurrent density of the FTO/ZnO/Cu2O/Ag@SiO2 photoanode (0.77 mA cm-2) at 1.23 VRHE exhibits an increment of 88%, and a cathodic shift of 0.1 V for the on-set potential (0.4 VRHE). Detailed photoelectrochemical analyses reveal that the Cu2O/ZnO p-n heterojunction formed between Cu2O and ZnO can effectively promote photogenerated carrier separation. The surface plasmonic effect of the Ag@SiO2 nanoparticles can further promote the photogenerated carrier transfer efficiency, which synergistically improves the PEC-WS performance.

Synthesis of a branched surfactant from the castor derivative and its surface properties.

A new class of ricinoleic acid-derived branched surfactant with a Y-shaped structure (ethoxylated monohydroxy stearic acid methyl ester, 12-HMEEn) was synthesized and characterized by introducing a polyoxyethylene head group in the hydroxyl position inside the molecule. The physicochemical properties and surface activities of 12-HMEEn with different degrees of ethoxylation at various concentrations were studied. The typical Y-shaped structure of the molecule facilitates its adsorption at the interface, which provides an excellent surface activity and affects its surfactant properties significantly. The dynamic contact angle, wettability, foaming properties, and compatibility tests of 12-HMEEn showed that it has good wetting performance, low foaming and fast defoaming properties, and good compatibility in formulation applications, indicating that the surfactant has potential application in industrial cleaning.

[Assessment of cognitive function, emotions and activities of daily living in patients with multiple system atrophy].

OBJECTIVE: To explore the cognitive function, emotional status and activities of daily living in patients with multiple system atrophy (MSA). METHODS: Thirty-two MSA patients and 38 healthy controls from October 2009 to November 2012 were recruited from our hospital. Their cognitive function, emotional status and activities of daily living were assessed. Cognitive function was assessed by Montreal cognitive assessment (MoCA) and mini-mental state examination (MMSE); emotional status by self-rating depression scale (SDS) and self-rating anxiety scale (SAS); daily living and activities by activities of daily living scale (ADL). Data analysis was performed with SPSS 19.0. And the results were presented as the mean ± standard deviation. Comparison of means was performed with independent sample t test. And Pearson's correlation test was used for correlation analysis. A P-value <0.05 was considered significant. RESULTS: Mild or moderate cognitive impairment was documented in 71.9% of MSA patients. The scores of MoCA and MMSE in the MSA group were significantly lower than those in the control group. And the scores of ADL, SDS and SAS in the MSA group were significantly higher than those in the control group (P < 0.05). MoCA subitems such as space/executive function, attention, abstraction, language and delayed memory of the MSA group were significantly lower than those of the control group (P < 0.05). A negative correlation existed between the scores of MoCA and MMSE with disease duration (P < 0.01). There was a positive correlation between the scores of SDS and SAS with ADL and disease duration (P < 0.05). And the relationship was significant between the scores of SDS and SAS (P < 0.01). A positive correlation existed between scores of ADL with disease duration (P < 0.05). CONCLUSION: MSA patients have certain degrees of cognitive impairment, emotion disorders and impaired ADL. Cognitive impairment in MSA patients may be more common than previously. Furthermore, the clinical features of cognitive impairment in these patients may have some clinical values for references.

The impact of emotional intelligence, self-esteem, and self-image on romantic communication over MySpace.

A study based on a survey of 240 individual MySpace users found that low self-esteem encourages young adults to engage in romantic communication (such as having intimate communication with the opposite sex and looking for romantic partners) while higher emotional intelligence discourages such activity. The results also suggested that those who have higher self-image, such as thinking themselves attractive and happy with their appearance, tend to engage in romantic communication. Limitations of the study and suggestion for future study are discussed.