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101.
In this paper, a highly efficient and environmentally-friendly dust depressor was developed based on the sodium lignosulfonate–acrylic acid graft copolymer. Using the grafting ratio as an index, a three-factor and four-level orthogonal experiment was conducted to optimize the fabrication conditions of the graft copolymer. At a reaction temperature of 60 °C, feed ratio mSLS–AA of 1 : 3, and FeSO4·7H2O content of 2.5%, the prototype produced the highest grafting ratio. The microstructure of the graft copolymer was measured using Fourier transform infrared spectrometry (FTIR) and nuclear magnetic resonance (1H-NMR). Furthermore, the influence of glycerol and the JFC penetrant on the contact angle between the compound solution and coal powder was investigated. Finally, four formulas of dust depressor were selected based on the experimental results. The dust-control performance of the four dust depressors was then tested on a large-scale spray dust suppression simulation platform. The results show that after applying formula 1 at various distances from the spray field, the average dust reduction rates of the total dust (respirable dust) at each point increased. Compared to the water-spraying dust suppression technique, the dust concentration is significantly reduced after the graft copolymer dust depressor is applied.

In this paper, a highly efficient and environmentally-friendly dust depressor was developed based on the sodium lignosulfonate–acrylic acid graft copolymer.  相似文献   
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运用文献资料法、数理统计法和对比实验法等研究方法,对多媒体技术在高校羽毛球课堂教学中的应用研究,探讨多媒体技术对促进教学效果和提高学习效率中的作用与意义。结果表明:多媒体技术的运用符合高校羽毛球教学目标,并能够充分调动学生的积极性,更快建立完整、正确的技术动作表象,更好掌握技术要领,提高羽毛球教学效果,促进高校体育教师教学观念的转变和教学手段的现代化,适应现代教育的发展。  相似文献   
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Ascorbic acid (AA) as an essential vitamin in the human body participates in various physiological reactions and plays a key role in many biochemical processes. Therefore, it is of vital importance to monitor and quantify AA in commercial tablets, beverages and food. In this work, a rapid and ultrasensitive chemiluminescence (CL) system for the detection of AA was developed, in which ultrathin cobalt oxyhydroxide (CoOOH) nanosheets were applied in the conventional luminol–H2O2 CL system. The results showed that ultrathin CoOOH nanosheets as a catalyzer remarkably improved the CL intensity of the CoOOH–luminol–H2O2 system, up to about 1400-fold. Under the optimized conditions, the CL inhibition efficiencies increase linearly with the concentrations of AA in the range of 1–500 pmol L−1, and the limit of detection was 39 fmol L−1. Moreover, the proposed CL system was successfully applied in the determination of AA in medicinal tablets with satisfactory results.

An ultrasensitive CL system for the determination of ascorbic acid in medicinal tablets was developed based on the enhancement effect of cobalt oxyhydroxide nanosheets on the luminol–H2O2 system.  相似文献   
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A magnetic ionic liquids (MILs)-based aqueous two-phase system (MIL-ATPs) obtained by mixing with a series of inorganic salts, which involves five cholinium MILs with the piperidinyloxy radical anion is reported for the first time. Phase diagrams for the new ATPs were experimentally determined at different temperatures (298.15–318.15 K) and the liquid–liquid equilibrium data for two-phase systems were correlated according to the empirical nonlinear expression. The effects of the types of MILs, temperature and inorganic salts on the binodal curve are discussed in detail. The MIL-ATPs coupled with HPLC-UV analysis was developed in the quantitation of berberine hydrochloride in Rhizoma coptidis. Under optimal conditions, the partition coefficient of berberine hydrochloride was 127.68 with the precision values (RSD%) of 1.40% and 2.83% for intra-day (n = 6) and inter-day (n = 3), respectively. The limit of detection (LOD) and limit of quantification (LOQ) for berberine hydrochloride were 0.023 mg L−1 and 0.077 mg L−1, respectively. The recoveries were obtained in the acceptable range of 97.4–101.2%. Moreover, the content of berberine hydrochloride in the raw material of Rhizoma coptidis was measured as 123.95 mg g−1 with this method. Finally, 99.8% MIL was recovered for cycle application after the removal of berberine hydrochloride by using D101 resin. This study provides a meaningful reference for the application of MIL-ATPs with great prospects.

Five cholinium type organic magnetic ionic liquids have been applied in ionic liquid-based aqueous two-phase systems by mixing with a series of inorganic salts, which is reported to extract berberine in quantitative analysis for the first time.  相似文献   
105.
Journal of Thrombosis and Thrombolysis - To comprehensively evaluate the clinical effects of low molecular weight heparin (LMWH) and aspirin for deep vein thrombosis (DVT) patients after...  相似文献   
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Abstract

The chitosan/gelatin hydrogel incorporated with biphasic calcium phosphate nanoparticles (BCP-NPs) as scaffold (CGB) for bone tissue engineering was reported in this article. Such nanocomposite hydrogels were fabricated by using cycled freeze-thawing method, of which physicochemical and biological properties were regulated by adjusting the weight ratio of chitosan/gelatin/BCP-NPs. The needle-like BCP-NPs were dispersed into composites uniformly, and physically cross-linked with chitosan and gelatin, which were identified via Scanning Electron Microscope (SEM) images and Fourier Transform Infrared Spectroscopy (FT-IR) analysis. The porosity, equilibrium swelling ratio, and compressive strength of CGB scaffolds were mainly influenced by the BCP-NPs concentration. In vitro degradation analysis in simulated body fluids (SBF) displayed that CGB scaffolds were degraded up to at least 30?wt% in one month. Also, CCK-8 analysis confirmed that the prepared scaffolds had a good cytocompatibility through in culturing with bone marrow mesenchymal stem cells (BMSCs). Finally, In vivo animal experiments revealed that new bone tissue was observed inside the scaffolds, and gradually increased with increasing months, when implanted CGB scaffolds into large necrotic lesions of rabbit femoral head. The above results suggested that prepared CGB nanocomposites had the potential to be applied in bone tissue engineering.  相似文献   
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