Optimization via response surface methodology of the synthesis of a dust suppressant and its performance characterization for use in open cut coal mines.

To relieve dust pollution in open cut coal mines and reduce the hazards of coal dust pollution to the environment and workers we optimized the synthesis of a dust suppressant by graft copolymerization of environmentally friendly soy protein isolate with methyl methacrylate. This dust suppressant could effectively control dust pollution in open cut coal mines. The optimized conditions for graft copolymerization in this case were determined by a response surface experiment designed with Design-Expert 10 software. Characterization by scanning electron microscopy showed a significant morphology change of the dust suppressant and the generation of a rigid and dense layer on its surface after interacting with coal dust. The layer exhibited good bonding and dust suppression performance. The analysis with Fourier-transform infrared spectroscopy revealed the appearance of new absorption peaks near 1300, 1072, and 1631 cm-1, demonstrating effective graft copolymerization. The proposed dust suppressant exhibited excellent wind erosion resistance, with a resistance that exceeded 90% at a wind speed of 6.5 m/sec. The successful graft copolymerization and effective bonding and curing of the dust suppressant on coal dust were experimentally verified. This is of great significance to the control of coal dust pollution.

Preparation and performance characterization of a new dust suppressant with a cross-linked network structure for use in open-pit coal mines.

In an effort to control dust pollution in open-air environments such as pit coal mines and coal transportation systems, a new dust suppressant with a cross-linked network structure was prepared. Graft copolymerization of soy protein isolate (SPI) and methacrylic acid (MAA), using potassium persulfate (KPS) as the initiator and hexametaphosphoric acid (SHMP) as the cross-linking agent, formed the network structure. The optimal MAA/SPI mass ratio for the dust suppressant was determined through a single-factor experiment to be 3:4, with 0.8 and 0.2 g of SHMP and KPS, respectively. The grafting reaction required 30 min at 60 °C. Scanning electron microscopy, energy-dispersive x-ray spectroscopy, Fourier-transform infrared spectroscopy, and differential scanning calorimetry were used to characterize the structure and application performance of the dust suppressant. The experimental results showed that the graft copolymerization reaction successfully formed the desired cross-linked network, and that when the cross-linked network material was sprayed on coal dust, it formed a dense, solidified shell, which effectively resisted wind erosion and served as a dust suppressant. The average reduction of the total suspended particulate matter of an open-air coal pile reached 79.95%, demonstrating effective dust suppression.

[Optimization of determination of astragaloside â £ in Astragali Radix by continuous single-factor method].

This paper aims to solve the problems of complicated-unstable test solution preparation process and insufficient extraction of the active ingredient astragaloside Ⅳ in the legal method for the determination of astragaloside Ⅳ in Astragali Radix. The continuous single-factor analysis of seven main factors affecting the content of astragaloside Ⅳ was carried out by HPLC-ELSD, and then the pre-paration method of test solution was optimized. This optimized method exhibited excellent performance in precision, repeatability and stability. The average recovery rate of astragaloside Ⅳ was 99.65% with RSD 2.2%. Astragaloside Ⅳ showed a good linearity between the logarithm of peak area and the logarithm of injection quantity in the range of 0.46-9.1 µg(r=0.999 6). The contents of astragaloside Ⅳ in 29 batches of Astragali Radix were determined by the new and the legal methods. The results showed that the average content of astragaloside Ⅳ in these Astragali Radix samples determined by the former method was 1.458 times than that of the latter one, indicating the new method was simple, reliable and more adequate to extract target compound. According to the results, it is suggested to improve the content standard of astragaloside Ⅳ in Astragali Radix in the new edition of Chinese Pharmacopeia.

Optimization of determination of astragaloside Ⅳ in Astragali Radix by continuous single-factor method / 中国中药杂志

This paper aims to solve the problems of complicated-unstable test solution preparation process and insufficient extraction of the active ingredient astragaloside Ⅳ in the legal method for the determination of astragaloside Ⅳ in Astragali Radix. The continuous single-factor analysis of seven main factors affecting the content of astragaloside Ⅳ was carried out by HPLC-ELSD, and then the pre-paration method of test solution was optimized. This optimized method exhibited excellent performance in precision, repeatability and stability. The average recovery rate of astragaloside Ⅳ was 99.65% with RSD 2.2%. Astragaloside Ⅳ showed a good linearity between the logarithm of peak area and the logarithm of injection quantity in the range of 0.46-9.1 μg(r=0.999 6). The contents of astragaloside Ⅳ in 29 batches of Astragali Radix were determined by the new and the legal methods. The results showed that the average content of astragaloside Ⅳ in these Astragali Radix samples determined by the former method was 1.458 times than that of the latter one, indicating the new method was simple, reliable and more adequate to extract target compound. According to the results, it is suggested to improve the content standard of astragaloside Ⅳ in Astragali Radix in the new edition of Chinese Pharmacopeia.

Optimization of prescription and preparation technology of brucine nanostructured lipid carriers / 中草药

Objective To optimize the prescription and preparation technology of brucine nanostructured lipid carriers (B-NLC). Methods The method of "the solvent emulsification ultrasound" was used to prepare B-NLC. The prescription and preparation was optimized using a single factor method combined with central composite design-response surface methodology (CCD-RSM). Results The resultant B-NLC was transparent liquid with light blue opalescence. The optimal conditions were that the dosage of drugs was 1.28 mg, the mass concentration of poloxamer 188 was 1.08%, and the ratio of solid lipid to liquid lipid was 1.45:1. The obtained NLC showed the average particle size of (136.89 ± 4.23) nm with a polydispersity index of 0.289 ± 0.005 and a zeta potential of (-34.46 ± 0.31) mV. The entrapment efficiency was calculated to be (68.98 ± 2.06)%, and the drug loading content was (1.90 ± 0.06)%. Conclusion B-NLC prepared by solvent emulsification ultrasound had a high entrapment efficiency and a narrow particle size distribution. The method was easy and simple and can be used to optimize the prescription and preparation of B-NLC, which provides a foundation for the further in vivo research of brucine.