基于UPLC-Q-TOF-MSE技术的三勒浆口服液上清液及沉淀部分化学成分分析

目的:分析三勒浆口服液上清液和沉淀部分的主要化学成分,为建立其质量标准与沉淀控制技术提供依据。方法:使用UPLC-Q-TOF-MS~E技术分别对分离后的上清液及沉淀部分化学成分进行定性分析,采用Waters ACQUITY UPLC BEH C18色谱柱(2. 1 mm×100 mm,1. 7μm),流动相选择0. 1%甲酸水溶液(A)-乙腈(B)梯度洗脱(0～1 min,2%B;1～2 min,2%～5%B;2～4 min,5%～7%B;4～6 min,7%～24%B;6～10 min,24%～42%B;10～12 min,42%～54%B;12～15 min,54%～76%B;15～18 min,76%～100%B),流速0. 3 mL·min~(-1),柱温30℃,进样量2μL。质谱分析采用电喷雾离子源(ESI),负离子模式下使用时间依赖型MSE方式采集样品质谱数据,采集范围m/z 50～1 200(上清液)和m/z 50～3 000(沉淀),通过对采集数据的保留时间、精确相对分子质量和二级质谱裂解碎片进行比对后鉴定化学成分。结果:在三勒浆口服液上清液中共鉴定了61个化合物,包括鞣质类、酚酸类、黄酮类、氨基酸类、有机酸类、脂肪酸类等;沉淀中共鉴定了15个化合物,包括鞣质类、酚酸类、黄酮类、脂肪酸类等。结论:三勒浆口服液的水解鞣质可能是该制剂潜在的沉淀物质基础,其沉淀物很可能是以鞣花酸和鞣红为主构成的复杂沉淀。建立的UPLC-Q-TOF-MS~E可快速、全面地分析三勒浆口服液的化学成分,可为其物质基础、沉淀机制及质量控制等研究提供科学依据。     

The Precipitation of Niobium Carbide and Its Influence on the Structure of HT250 for Automobile Wheel Hubs

Improving the strength of grey cast iron wheel hubs will improve the safety of automobiles and have a great significance for energy saving and environmental protection. This paper systematically compares the calculation results of Python-based precipitation calculation and JmatPro software simulation with experiments. The results show that with a low mass fraction of niobium (0.098%) cuboid Niobium Carbide (NbC) precipitates do not form in the liquid phase; however, an elongated NbC niobium-rich phase may form during the solidification process and in the solid phase. However, cuboid NbC precipitates can be precipitated from the liquid phase when the niobium mass fraction is higher (0.27%, 0.46%). These results indicate that with the increasing niobium content the amount, particle size, and initial precipitation temperature of niobium carbide precipitated in the matrix structure will increase. According to the observation and statistical analysis of the microstructure, it is found that tensile strength will be improved with an increase in niobium content due to the refinement of the graphite and pearlite interlamellar spacing. In this paper, adding less than 0.32% of Nb to grey cast iron is recommended, considering the comprehensive cost and the effect of niobium in the material structure.     

以光卤石为原料制取磷酸二氢钾的工艺

以天然光卤石为原料生产ＫＨ２ＰＯ４,提出了最佳工艺条件．采用高氯酸铵（ＮＨ４ＣｌＯ４）加入光卤石饱和溶液,经沉淀、过滤得高氯酸钾（ＫＣｌＯ４）,再将此ＫＣｌＯ４ 加入磷酸中,以叔胺类萃取剂萃取去除高氯酸（ＨＣｌＯ４）获得ＫＨ２ＰＯ４．萃出的ＨＣｌＯ４ 经氢氧化铵水溶液反萃所得的ＮＨ４ＣｌＯ４ 可循环使用．光卤石中钾的回收率达９４％ ,所得ＫＨ２ＰＯ４ 的纯度为９９．１％ ．     

Mechanism of Sand Cementation with an Efficient Method of Microbial-Induced Calcite Precipitation

This paper presents an efficient method of microbial-induced calcite precipitation (MICP) for cementation of sand particles. First, the influence of initial pH value of the culture medium on the growth of bacteria was discussed. Then, the compressive strength and calcium carbonate content of cemented sand columns with different sand particle sizes were measured to indicate the cementation effectiveness. The microstructure of cemented sand columns as well as the mineral composition and distribution of calcium carbonate were characterised by means of scanning electron microscopy-energy dispersive spectrometer (SEM-EDS) and X-ray diffraction (XRD). The results showed that the urease-producing bacteria S. pasteurii can be cultured at the initial pH values of 7–10, while a higher pH (e.g., 11) would hinder its growth and decrease its urease activity. The injection method of MICP with high standing time can cement sand columns effectively. Small average sand particle size of sand columns and high injection cycles can facilitate the gain of compressive strength, while calcium carbonate content of sand column higher than 8% can promote the increase of compressive strength. XRD results indicate that the fine grains generated on the surface of sand particles are calcite. The distribution of calcite on sand particles’ surface is broad and uniform. First, calcite was precipitated on the surface of sand particles, and then a precipitation layer was formed, which would connect sand particles through its high enough thickness and contribute to the development of compressive strength of the whole sand column.     

Nutrients Recovery from Dairy Wastewater by Struvite Precipitation Combined with Ammonium Sorption on Clinoptilolite

Struvite precipitation from Wastewater involves an excess of ammonium to create a supersaturated initial solution. The remaining fraction can be a threat to the environment. This work combined struvite precipitation and ammonium sorption using natural zeolite to decrease the ammonium level in the effluent. Two approaches of estimation of feed sample doses were used. One consisted of gradient experiments for ammonium precipitation to the asymptotic level and was combined with clinoptilolite to lower the ammonium level in the effluent. This approach used doses of 0.05:1.51:0.61:1 of Ca:Mg:NH₄⁺:PO₄³⁻ mole ratios, respectively. In contrast, three level design with narrowed NH₄⁺:PO₄³⁻ range reached 0.25:1.51:0.8:1 for Ca:Mg:NH₄⁺:PO₄³⁻ mole ratios. The addition of zeolite decreased effluent ammonium concentration. In both ways, the P and N recoveries were higher than 94% and 72%, respectively. The complexity of the precipitation mixture decreased the ammonium sorption capacity (Q_e) of clinoptilolite from Q_e of 0.52 to 0.10 meq∙g⁻¹ in single and complex solutions, respectively. Thermodynamically, the addition of 1.5 % of clinoptilolite changed the struvite precipitation spontaneity from ∆G of −5.87 to −5.42 kJ·mol⁻¹ and from 9.66 to 9.56 kJ·mol⁻¹ for gradient and three level experimental procedures, respectively. Thus, clinoptilolite demonstrated a positive effect on the struvite precipitation process and its environmental impact.     

Formation of Polymer-Carbon Nanotube Composites by Two-Step Supercritical Fluid Treatment

An approach for polymer-carbon nanotube (CNT) composite preparation is proposed based on a two-step supercritical fluid treatment. The first step, rapid expansion of a suspension (RESS) of CNTs in supercritical carbon dioxide, is used to de-bundle CNTs in order to simplify their mixing with polymer in solution. The ability of RESS pre-treatment to de-bundle CNTs and to cause significant bulk volume expansion is demonstrated. The second step is the formation of polymer-CNT composite from solution via supercritical antisolvent (SAS) precipitation. SAS treatment allows avoiding CNT agglomeration during transition from a solution into solid state due to the high speed of phase transition. The combination of these two supercritical fluid methods allowed obtaining a polycarbonate-multiwalled carbon nanotube composite with tensile strength two times higher compared to the initial polymer and enhanced elasticity.     

Thermal Mass Effect on the Solution Cooling Rate and on HIPped Astroloy Component Properties

Astroloy is a Ni-based superalloy with high-volume fraction of γ′, which gives high temperature properties but reduces its forgeability. Therefore, powder metallurgy manufacturing processes such as Near Net Shape HIPping are the most suitable manufacturing technology for Astroloy. However, NNSHIP has its own drawbacks, such as the formation of prior particle boundaries (PPBs), which usually tend to decrease material mechanical properties. The detrimental effect of PPBs can be reduced by optimizing the entire HIP processing route. Conventional HIP cycles have very low cooling rates, especially in big components from industry, and thus a series of post-heat treatments must be applied in order to achieve desirable microstructures and improve the mechanical properties. Standard heat treatments for Astroloy are long and tedious with several steps of solutioning, stabilization and precipitation. In this work, two main studies have been performed. First, the effect of the cooling rate after the solutioning treatment, which is driven by the materials’ thermal mass, on the Astroloy microstructure and mechanical properties was studied. Experimental analyses and simulation techniques have been used in the present work and it has been found that higher cooling rates after solutioning increase the density of tertiary γ′ precipitates by 85%, and their size decreases by 22%, which leads to an increase in hardness from 356 to 372 HB30. This hardness difference tends to reduce after subsequent standard heat treatment (HT) that homogenizes the microstructure. The second study shows the effect of different heat treatments on the microstructure and hardness of samples with two different thermal masses (can and cube). More than double the density of γ′ precipitates was found in small cubes in comparison with cans with a higher thermal mass. Therefore, the hardness in cubes is between 4 and 20 HB 30 higher than in large cans, depending on the applied HT.     

Coordination of Noble Metals in Poly(vinyl mercaptoethanol) Particles Prepared by Precipitation/Emulsion Polymerization

S-Vinyl monomers react readily in radical polymerizations resulting in polymers with interesting features such as enhanced refractive indices, increased thermal stability, or the ability to coordinate various metals. Among them, vinyl mercaptoethanol (VME) can be produced in industrial scale, but the poor solubility of the resulting homopolymer limits its application. In this contribution, polymerizations of the monomer are investigated in water forming a heterogeneous system. The good solubility of the monomer in water imparts the system with mixed characteristics between a precipitation and an emulsion polymerization. Evaluating various surfactants, only polyvinyl alcohol (PVA) is found to create stable dispersions, although micrometer-sized particles are formed with a broad size distribution. Nevertheless, the particles are able to coordinate silver or gold ions. Attempts to reduce the noble metal ions by commercial reducing agents fail. However, exposure to sunlight unexpectedly results in a controlled reduction of the metal ions and the formation of composite particles. Silver ion-containing dispersions demonstrate strong antibacterial properties, while the effect is diminished in the corresponding composite. Overall, the precipitation/emulsion polymerization of VME represents a promising pathway to stable sulfur-rich polymer dispersions with the ability to coordinate metal ions or form reactive metal composites.     

醇料比对双黄连制剂醇沉效果及沉淀物形态影响

目的研究醇料比对双黄连制剂醇沉效果及沉淀物形态的影响,探讨醇沉沉淀物分形维数综合评价醇沉效果的可行性。方法针对双黄连制剂醇沉工艺,采用HPLC法与重量分析法,考察醇料比对指标成分综合保留率与滤饼含液率的影响;采用直接观察、原子力显微镜观察及"面积-周长"法,考察醇料比对沉淀物表观形态、微观形态及分形维数的影响。运用Pearson相关分析方法,分析醇沉沉淀物分形维数分别与指标成分综合保留率和滤饼含液率之间的相关性。结果随着醇料比的增大,指标成分综合保留率与沉淀物分形维数均逐渐增大,而滤饼含液率则逐渐减小;沉淀物分形维数与指标成分综合保留率呈正相关,与滤饼含液率呈负相关。结论在双黄连制剂醇沉工艺中,醇沉沉淀物分形维数可作为反映醇沉效果的综合评价指标,以期为后续双黄连制剂醇沉工艺可视化的精细控制研究提供参考。     

基于质量源于设计（QbD）理念研究参麦注射液醇提水沉工艺

目的基于质量源于设计(QbD)理念以及满意度算法优化参麦注射液醇提水沉工艺。方法使用危害及可操作性分析法对参麦注射液醇提水沉工艺进行风险评估,筛选出乙醇体积分数、提取时间、醇料比为醇提关键工艺参数,静置体系pH值、静置温度、静置时间为水沉关键工艺参数。采用Box-Behnken实验设计建立2个工艺环节的关键工艺参数和关键质量属性之间的多元线性回归模型,根据各质量属性的合格标准计算获得基于概率的麦冬醇提与混合水沉工艺的设计空间并进一步用基于满意度函数的多指标优化算法优化确定最佳操作条件。结果对麦冬的醇提工艺而言,在设计空间范围内,乙醇体积分数89.0%、提取时间110 min,醇料比2.99时总体满意度最优,满意度为0.722。对混合水沉工艺而言,当物料pH值为4左右时,在2.0℃静置40 h时工艺的总体满意度最优,满意度为0.995;当物料pH值为5左右时,在2.0℃静置35 h时工艺的总体满意度最优,满意度为0.999。结论基于QbD理念以及满意度算法确定的最佳条件有利于在保证产品质量的同时最大化降低生产成本,本研究对指导中药的制药工艺研究与工业化生产具有参考价值。