Experimental study on ratio optimization and application of improved bonded dust suppressant based on wetting effect.

Traditional bonded dust suppressants have high viscosity, insufficient fluidity and poor permeability problems, which is adverse to the formation of a continuous and stable solidified layer of dust suppressant solution on the surface of a dust pile. Gemini surfactant has efficient wetting performance and environmental protection performance, it is introduced as a wetting component to improve the flow and penetration performance of bonded dust suppressant solution, polymer absorbent resin (SAP) and sodium carboxymethyl starch (CMS) were selected as the main components of dust suppressant. A proportioning optimization model was constructed based on response surface methodology (RSM), and the concentration of each dust suppression component was selected as the independent variable, water loss rate, moisture retention rate, wind erosion rate and solution viscosity were chosen as the dependent variables in this model. The optimal formulation of the improved bonded dust suppressant was obtained by analyzing the laboratory experiments and field tests data. The results show that the effective time (≥15d) of the newly developed dust suppressant is 45 times longer than that of pure water (≈1/3d), and 1.875 times longer than that of the comparative dust suppressant (8d), the comprehensive cost is 27.36% lower than that of the similar dust suppressant product for mining enterprises.Implications: This paper presents the research idea of optimizing the bonded dust suppressant based on the improvement of wetting performance. And the paper used response surface method to obtain a wetting and bonding composite dust suppressant formulation. The field test shows that the dust suppressant has good dust suppression performance and economic benefits. This study laid the foundation for the development of new and efficient dust suppressants, and had important theoretical and application values for reducing dust environmental hazards and preventing occupational diseases.

Three new species of Rabigus Mulsant amp; Rey (Coleoptera, Staphylininae, Philonthina) from China.

The paper reports three new species of the genus Rabigus Mulsant Rey from China, namely, Rabigus cuspus Fei Zhou, sp. nov. from Sichuan, Rabigus sagittus Fei Zhou, sp. nov. from Shanxi, Rabigus triquetrus Fei Zhou, sp. nov. from Beijing and Shanxi. For all species included we provide color plates of general morphology and detailed aedeagus structures.

Revision of emEccoptolonthus/em Bernhauer (Coleoptera: Staphylininae: Philonthina) with descriptions of four new species from China.

This study revises the taxonomy of the genus Eccoptolonthus Bernhauer, 1912 and reports 14 species in the Chinese fauna. A catalogue of the remaining 15 Eccoptolonthus species from the Oriental and Afrotropical regions is also provided. Four new species are described from China: Eccoptolonthus conaensis Fei Zhou, sp. nov. from Tibet, Eccoptolonthus fuyuensis Fei Zhou, sp. nov. from Zhejiang, Eccoptolonthus dafoensis Fei Zhou, sp. nov. from Guizhou, and Eccoptolonthus xiaolongmenensis Fei Zhou, sp. nov. from Beijing. Eccoptolonthus (Eumorimotous) laevigatus laevigatus (Fauvel, 1895) is reported for the first time from Yunnan in China and Vietnam. A preliminary key to the Chinese species of Eccoptolonthus is also included in the paper. Color images and line drawings are provided to show diagnostic characters.

[Simultaneous determination of three inorganic anions in food-grade lubricating oils by chromatography with suppressed conductivity detection].

An ion chromatographic (IC) method with suppressed conductivity detection was developed for the simultaneous determination of Cl-, NO3(-), SO(2-)(4) in food-grade lubricating oils. After ultrasonic extraction with 50% (v/v) methanol aqueous solution and centrifugation, the sample in aqueous phase was purified with 0. 22 µm hybrid fiber membranes, then analyzed by IC using 15 mmol/L KOH solution as eluent, and detected by a suppressed conductivity detector. Effects of the concentration and flow rate of the eluent, and the concentration of the methanol aqueous solution on the detection of the three anions were investigated. Under the optimized separation conditions, the three anions were separated completely and the system peaks didn't interfere with the determination. The calibration curves showed good linearity (R2> 0. 999) in the range of 0. 10-20. 00 mg/L. The limits of detection (LODs, S/N= 3) were 0. 01 - 0. 03 mg/kg. The average recoveries of Cl-, NO(-)3, SO(2-)4 anions were 90. 0% - 103. 6% with the relative standard deviations (RSDs) of 2. 8% - 5. 7%. This method avoids the time-consuming pretreatment process to burn or ash the oil phase matrix, and can determine the amounts of three inorganic anions (Cl-, NO(-)3, SO(2-)(4)) in food-grade lubricating oils fast and accurately. It is suitable for simultaneously separating and detecting trace inorganic anions in lubricating oils or other oil products.