Ferulic acid and EGCG alter the structural characteristics of ovalbumin and its application in mineral loading

This study aims to fabricate mineral-loading nanocarriers using natural materials. The interaction patterns between ovalbumin (OVA) and four water-soluble polyphenols, namely ferulic acid (FA), (-)-Epigallo-catechin 3-gallate (EGCG), gallic acid (GA) and epicatechin (EC), were investigated. Results showed that the optimised conditions for preparing stable OVA–polyphenol complexes are at the OVA–polyphenol ratio of 4:1 at pH 6, under which OVA–FA and OVA–EGCG showed the highest stability and mineral-loading capacity among four OVA–polyphenol complexes. The fluorescence results indicated that the addition of EGCG and FA induced a significant fluorescence quenching to OVA. The interaction between OVA and polyphenols involved hydrogen bonding, hydrophobic interaction and electrostatic interaction. Fourier transform infrared spectroscopy (FTIR) analysis suggested that both FA and EGCG enhanced the stability and orderliness of the structure of OVA. The transmission electron microscopy images also exhibited the spherical structure of OVA after the addition of FA and EGCG. Furthermore, scanning electron microscope–energy dispersive X-ray spectrum results suggested that OVA–FA and OVA–EGCG complexes were better mineral carriers than OVA–GA and OVA–EC. This study may serve as the theoretical support for the promising application of OVA in the fabrication of mineral-loading nanocarriers in functional food and pharmaceutic.     

Directional separation of hydrogen-containing gas mixture by hydrate-membrane coupling method

Recovery of hydrogen (H₂) from H₂-containing gas mixtures has great significance for energy conservation, cost reduction and benefit increase. However, the common separation methods have the ubiquitous problem due to phase equilibrium principle and results in the conflict between H₂ concentration and H₂ recovery rate in the product gas. Consequently, an innovative conception of hydrate-membrane coupling approach is proposed in this work. In the separation process, hydration and membrane permeation two separation driving forces coexist to achieve the aim of strengthening mass transfer kinetics. H₂ and non-H₂ components (hydrocarbons) are synchronously and directionally selected by membrane and hydrate to improve different phase compositions. Therefore, the gas in feed side could keep relatively high two separation driving forces (H₂ fugacity and hydrocarbons fugacity). The results show that the coupling method could synchronously increase both the concentration and the recovery rate of H₂ in the product gas. At the same time, the volume and concentration of the hydrocarbons in hydrate both increases effectively. It indicates that hydrate and membrane separation methods support each other in the separation process. The hydrate-membrane coupling method fundamentally solves the issue of the decreasing driving force resulting from single separation method and phase equilibrium relationship.     

天然黏土矿物在靛蓝染色废水电絮凝中的应用

为提高靛蓝染色废水电絮凝处理效率,以天然黏土矿物为协同吸附剂,采用电絮凝-吸附联合工艺处理靛蓝染色废水。探究黏土类型对絮体沉降速率和Zeta电位的影响,通过废水色度、浊度、脱色率和化学需氧量(COD)去除率评价絮凝处理效果。确定最佳黏土矿物种类并结合絮体显微观察,进一步分析黏土矿物与电絮凝的协同作用机制。结果表明:黏土矿物加入可降低Zeta电位绝对值;硅藻土与电絮凝协同的主要絮凝机制为网捕卷扫,同时兼具一定的电荷中和与吸附架桥作用;电絮凝反应结束后,仅需加入1 g/L硅藻土反应3 min,Zeta电位绝对值可达到最低,为15.585 mV,废水脱色率提升至94.08%。     

SiO2对CaO-Fe2O3熔体结晶矿物组成及显微结构的影响

摘要：由于近年来低品位铁矿石的使用量增加，导致烧结过程中SiO2含量升高。SiO2是烧结矿中主要的脉石成分，其含量的变化与烧结矿最终质量密切相关。运用X射线衍射、光学显微镜和SEM-EDS方法研究了SiO2对CaO-Fe2O3熔体结晶矿物组成及显微结构的影响。研究结果表明，随着SiO2含量的增加，CaO-Fe2O3-SiO2熔体结晶产物中CaFe2O4(CF)含量减少而富铁铁酸钙(SFC)含量增加，CaFe2O4和SFC分别以块状和板条状析出，SFC的晶体结构随着SiO2含量的增加从Ca36Fe144O25-2向SFCA-I转变；当SiO2的质量分数超过3.0%时，椭圆状的Ca2SiO4（C2S）从熔体中结晶，其含量随SiO2含量的增加而增加，另有大量圆点状玻璃相分布于铁酸钙基体表面。     

老矿山残矿资源回收方案设计中三维探测及建模技术的应用

目前我国绝大多数中小型老矿山残矿回收面临一系列问题，包括资料缺失无法准确判定老采空区及剩余资源位置，无法准确掌握剩余资源形态及可回收量，回收方案设计与实际资源相差较大等。通过将三维探测及建模技术应用于老矿山残矿资源精准定位及回收方案设计中，有助于解决以上问题。以福建浦城屏峰硫铅锌矿为例，通过对老采空区采用三维激光扫描构建采空区三维模型，结合三维建模计算，构建了目前可回收的剩余资源三维模型。通过模型划分及切割，按照矿体实际形态，在三维模型中布设采切及穿孔工程，并将其导入平面施工图中，不仅可以减少设计工作量，而且能够精准匹配矿体，减少设计偏差。由于周边存在大量老采空区，为保障安全，在采空区及剩余资源精准三维模型的基础上，制定了采空区稳定性监测方案，布设了监测传感器，保障了资源回收安全。     

Mineral Oil Hydrocarbons (MOSH/MOAH) in Edible Oils and Possible Minimization by Deodorization Through the Example of Cocoa Butter

Mineral oil hydrocarbons (MOH) are present in many fats and oils as well as foods prepared thereof. A survey of mineral oil saturated hydrocarbons (MOSH) and mineral oil aromatic hydrocarbons (MOAH) in different types of vegetable fats and oils is reported. Contents of MOSH/MOAH were quantified using liquid chromatography online‐coupled to gas chromatography with flame‐ionization detection (LC‐GC‐FID). Cocoa butter (n = 142) showed levels from <LOQ (2.5 mg kg^?1) to 162 mg kg^?1 ΣMOSH (sum of C10–C50) and <LOQ to 55 mg kg^?1 ΣMOAH, in palm oil (n = 21) ΣMOSH were quantified from <LOQ to 124 mg kg^?1 and ΣMOAH from <LOQ to 39 mg kg^?1. Sunflower oil showed lower levels: ΣMOSH were determined in the range of <LOQ to 17 mg kg^?1 and MOAH were not observed at all. A possible influence of deodorization and a subsequent minimization of MOSH/MOAH was investigated. Systematic model‐experiments were performed on laboratory scale using spiked cocoa butter. Significant minimization of volatile MOH subfractions ≤C24 were observed at a deodorization temperature of 210 °C. Deodorization can be considered as an important processing step to reduce or even remove volatile MOSH/MOAH ≤C24. Practical Applications: Regardless of their possible entry routes into the food chain, volatile fractions of MOSH/MOAH can be removed by deodorizing vegetable fats and oils. This model‐study identifies the temperatures of deodorization that provide a significant improvement toward minimization of undesired MOSH/MOAH.     

Investigation of the energy-size reduction and mineral liberation of raw coal in the Hardgrove mill

Raw coal was ground in a Hardgrove mill, and mineral liberation from coal was investigated by float-sink test and electron probe microanalyzer (EPMA). Based on EPMA, associated conditions of mineral were determined. Analyses of energy-size reduction show that energy efficiency decreases with time. For +0.074 mm progenies, yields of particles in ?1.5 g.cm^?3 decrease with the increase of size and time, and products in +1.8 g.cm^?3 show the opposite trend. EPMA of 0.25–0.125 mm, 1.5–1.8 g.cm^?3 products ground for 10 min indicates that only part of minerals are liberated. For ?0.074 mm products, the yield of particles in ?1.5 g.cm^?3 decreases by 23.36% in last several minutes, but ash content of +1.8 g.cm^?3 also decreases by 13.18%. Since breakage of raw coal in last 9 min does not reduce particle size obviously, and liberation degree cannot be improved dramatically, closed grinding of 10 min in Hardgrove mill is proper to balance the size reduction and mineral liberation.     

飞灰固结体在沥青混合料中应用研究

通过对新型固结剂固化飞灰生成的固结体研磨成微粉全部或部分替代矿粉作为沥青混合料进行试验探究。试验结果表明,当微粉替代矿粉时,混合料的物理性能、水稳定性及高温稳定性得到了提高,确定了微粉替代矿粉最佳替代率。微粉在沥青混合料中重金属的存在状态采用多级提取的方法进行分析,试验结果进一步证明了微粉中重金属在沥青混合料中的长期稳定性。为焚烧垃圾飞灰固化稳定化和资源化利用提供了一定的理论指导。     

Detection of fresh palm oil adulteration with recycled cooking oil using fatty acid composition and FTIR spectral analysis

There is a growing concern over the food safety issue related to increased incidence of cooking oil adulteration with recycled cooking oil (RCO). The objective of this study was to detect fresh palm olein (FPO) adulteration with RCO using fatty acid composition (FAC) and Fourier-transform infrared spectroscopy (FTIR) spectral analyses combined with chemometrics. RCO prepared in the laboratory was mixed with FPO in the proportion ranged from 1% to 50% (v/v) to obtain the adulterated oil samples (AO). FACs for FPO, RCO, and AO were determined using gas chromatography equipped with a flame ionization detector (GC-FID). The compositions of most fatty acids in RCO lied within the normal ranges of Codex standard, except for C8:0, C10:0, C11:0, C15:0, trans C18:1, and polyunsaturated fatty acids (PUFAs), C20:5. PUFAs showed a consistent decreasing trend with increasing magnitude of change with respect to increasing adulteration level and thus might be a good indicator for detecting FPO adulteration with RCO. The evaluation parameters (coefficient of determination, root mean standard error) of the FTIR-partial least square (PLS) model of palm oil adulteration with recycled oil are R² = 0.995 and 3.25, respectively. For FTIR spectral analysis, the distinct variations in spectral regions and aberrations in characteristic bands between FPO and RCO were observed. The optimized PLS calibration model developed from normal spectral of the combined region at 3602–3398, 3016–2642, and 1845–650 cm^?1 overpredict the adulteration level. On the other hand, the discriminant analysis classification model was able to classify the FPO and AO into two distinct groups. Improvement of the principles of combined techniques in authenticating AO from fresh oil is beneficial as a guideline to detect adulteration in cooking oil.     

益生菌发酵对红枣汁抗氧化活性、营养品质及香气的影响

选取6种商业益生菌分别对红枣汁进行发酵，研究其对红枣汁的抗氧化活性、理化指标及香气的影响。结果表明，益生菌发酵可显著提高红枣汁的抗氧化能力，果321复合菌发酵枣汁的DPPH自由基清除能力最强，为573.83 mg/L，而植物乳杆菌（Lactobacillus plantarum）发酵枣汁的ABTS自由基清除能力最强，为1 034.00 mg/L，瑞士乳杆菌（Lactobacillus helveticus）发酵枣汁的铁离子还原力（FRAP）值最高，为1 366.34 mg/L。瑞士乳杆菌的产酸性能较好，发酵后产乳酸量约0.45 mg/L，总多酚和总黄酮含量分别较红枣汁提高了2.94%和2.85%。电子鼻分析结果表明，益生菌发酵可显著改变红枣汁的香气成分，且线性判别分析（LDA）对红枣汁香气物质的区分和识别效果优于主成分分析（PCA），发酵红枣汁的特征风味主要来源于硫化物、萜烯类、广谱甲基类、氮氧化物、乙醇和芳香型化合物。