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Co9S8 and transition metal hydroxides are both potential pseudo-capacitance electrode materials for supercapacitors. Co9S8 has a large specific capacitance and electrochemical activity, and transition metal hydroxides have the advantages of high capacitance and redox activity due to their multiple valence metals and open layered structure. In this study, Co9S8 and NiCoLDH are used to form a Co9S8–aCNT–NiCoLDH composite electrode material by twining acidified carbon nanotubes (aCNTs) around hollow Co9S8 rods and then compounding nickel cobalt hydroxide (NiCoLDH) on the outside. aCNTs provide more electronic channels, which bring more active electrochemical reactions and absorb the volume expansion of Co9S8. The hollow Co9S8 rods and flower-like NiCoLDH structures ensure that the electrode has a highly open structure, which increases the contact area with the electrolyte and is beneficial for ion transport. The outer NiCoLDH can also reduce the volume expansion of Co9S8. These advantages ensure the high specific capacitance and rate performance of the Co9S8–aCNT–NiCoLDH electrode material. Co9S8–aCNT–NiCoLDH was used as the positive material to fabricate asymmetric supercapacitors with attractive energy density and power density, which further proved its excellent electrochemical performance. [ABSTRACT FROM AUTHOR]

Objective: To investigate and compare the effects of maxillary protraction therapy on Class III patients with unilateral cleft lip and palate (UCLP) and Class III patients with noncleft. Design: Prospective controlled clinical trial. Patients: Twenty-six Class III patients with UCLP (mean age: 10.32 ± 1.29 years) and 26 Class III patients with noncleft (mean age: 9.82 ± 1.03 years) were included and treated with maxillary protraction therapy. Interventions: Maxillary protraction therapy was performed with an intraoral Hyrax appliance and extraoral facemask. Cone beam computed tomography scans were taken before and after treatment. Pretreatment skeletal and dental characteristics and treatment changes were analyzed and compared. Results: The average treatment duration was 18.44 ± 4.16 months in the UCLP group, which was substantially longer than the 12.46 ± 4.03-month average treatment duration in the noncleft group (P <.001). No significant difference was found in the maxillary changes (length, advancement of point A, and SNA angle) and improvement of intermaxillary relationship (ANB angle) between the 2 groups. The UCLP group had 1.40° more mandibular clockwise rotation (P =.034). Regarding dental changes, the UCLP group had more upper incisor proclination (P =.006) and less lower incisor retroclination (P =.023). Conclusions: Approximately extended maxillary protraction therapy in patients with UCLP could be as effective as in patients with noncleft. Further study is required to follow patients until completion of growth to elucidate the long-term stability of the treatment. [ABSTRACT FROM AUTHOR]

A novel oxidative decarboxylative C–H alkylation of phenanthridines with carboxylic acids was developed for the efficient synthesis of multi-substituted phenanthridine derivatives. The given method features easy availability of starting materials, high regioselectivity, and mild conditions. Furthermore, a one-pot synthesis of multi-substituted phenanthridine derivatives was realized by the reaction of biphenyl isocyanides and carboxylic acid. [ABSTRACT FROM AUTHOR]

Summary: Large confined space has high incidence of fires, which seriously threatens the safety of people working there. Understanding the distribution of smoke in such large space is critical to fire development prediction and smoke control. Three improved methods for the stratification interface prediction of fire smoke are developed, including of improved intra‐variance, integral ratio and N‐percentage methods. In these methods, the interface height is determined by the vertical temperature distribution based on a three‐layer smoke zone model, which is an improvement of a two‐layer zone model. Thereafter, the three improved methods are applied to several typical fire cases simulated CFD to predict the smoke interface, and their applicability and reliability are verified by comparison of the smoke stratification results with the filed simulation results. Results show that the three improved methods can effectively determine the location of the three‐layer zone model's interface, and they have the ability to predict smoke interface for fires with different fire source types and ventilation conditions. [ABSTRACT FROM AUTHOR]

Serious haze-fog problems in Beijing have aroused considerable concern. The objectives of this study are to determine elemental concentrations in PM2.5, assess their enrichment in PM2.5, and identify their sources during winter in Beijing. Daily PM2.5 samples were collected at the Beijing Normal University campus from January 28 to February 27, 2014. Twenty-three metal elements were determined following digestion by using inductively coupled-plasma mass spectrometry (ICP-MS). The daily PM2.5 concentration ranged from 21.8 to 474.3 μg m−3, with a mean of 172 μg m−3. The daily PM2.5 concentration exceeded 75 mg m−3 (China ambient air quality standards: grade II) for 23 days of the month; therefore, ambient air pollution was severe. The median of daily elemental concentrations in the air decreased in the order of K, Na, and Al (> 103 ng m−3); Ca, Fe, Mn, Mg, Zn, Pb, and Cu (> 102 ng m−3); Ba, P, Ti, and Sr (> 10 ng m−3); and Rb, Sb, Ga, V, Ce, Cd, Tl, Li, La, and Co (> 1 ng m−3). Average and median values of enrichment factors were > 100 for Cd, Sb, Pb, Cu, Zn, and Tl but < 10 for Sr, V, K, Co, Na, Li, Rb, La, Mg, Ce, Ca, Fe, and Al. Enrichment factor, correlation, and principal component analyses demonstrated that Cd, Sb, Pb, Cu, Zn, and Tl in PM2.5 mainly originated from anthropogenic sources, whereas V, Co, Na, Li, Rb, La, Ce, Fe, and Al mainly originated from lithogenic sources. However, the ignition of fireworks during Spring Festival resulted in three pronounced peaks of Ba, K, Mg, Sr, and Cu concentrations. Therefore, national and local governments should continue controlling atmospheric emissions of toxic heavy metals and prohibit firework displays in megacities during Spring Festival. [ABSTRACT FROM AUTHOR]