Protein is the most important characteristic component of honey. The types and content of proteins in different kinds of honey are imparity, but those in the same kind of honey are very similar. Capillary zone electrophoresis (CZE) method, used to detect proteins, was developed for authenticating of four mono-floral honeys (n = 45), including medlar honey, chaste honey, jujube honey and locust honey. Electrophoresis conditions including capillary inner diameter (50–70 μm), pH (2.5–9), the concentration of anionic surfactant (0.3–0.5 mmol L−1), injection time (3–7 s) and separation voltage (3–7 KV) were optimized. The results showed that the honey sample was highly stable and the detection limit was 10%, the relative standard deviation of retention time and peak area were lower than 1.40% and 1.76%, respectively. The CZE fingerprints were established on the basis of different protein characteristics in different mono-floral honeys combined with chemometric analysis. All 45 honeys could be correctly identified according to their floral origins. This method does not need to confirm the type of protein, and has the advantages of simple and fast verification of the authenticity of honey.

本文利用非糖物质快速鉴别四种常见的单花蜂蜜(枸杞蜂蜜、荆条蜂蜜、枣花蜂蜜和洋槐蜂蜜).利用固相萃取除糖提取蜂蜜非糖物质,并用高效液相色谱(HPLC)结合化学计量学进行蜂蜜花源的判定.发现了四种单花蜂蜜的非糖特征标志物.芦丁、丁香酸甲酯、阿魏酸的含量在四种蜂蜜中差异最大.对羟基苯甲酸和脱落酸在枸杞蜂蜜中平均含量分别为0.59 μg/g和0.42 μg/g,可作为枸杞蜂蜜的花源标志物;对香豆酸和肉桂酸在荆条蜂蜜中平均含量为0.08μg/g和0.05 μg/g,可作为荆条蜂蜜的潜在花源标志物;阿魏酸、异阿魏酸是枣花蜂蜜的特征标志物,平均含量分别为0.40 μg/g和0.76 μg/g;洋槐蜂蜜的特征标志物是芦丁和丁香酸甲酯,平均含量为0.08 μg/g和0.14 μg/g.利用高效液相色谱指纹图谱结合化学计量学方法(主成分分析和判别分析),四种单花蜂蜜依据其花源被成功区分.本研究对蜂蜜真实性判定有重要参考价值,为后续蜂蜜真伪鉴别奠定基础.

A novel extraction process to recover lithium ions from simulated salt lake brines with high Mg/Li ratio was developed. Tributyl phosphate (TBP), FeCl3 and diethyl succinate were used as extractant, co-extraction agent and diluent, respectively. Effects of extraction conditions containing the volume concentration of TBP, Fe/Li molar ratio and O/A phase ratio on extraction performances were studied. The highest one-stage extraction efficiency of lithium ions and separation factor were about 65% and 350, respectively. In addition, the third phase did not appear over all the volume concentrations of TBP. HCl + MgCl2 and HCl + NaCl were used as washing and stripping agents, respectively. Effects of washing and stripping conditions on washing and stripping performances were investigated too. Mg(OH)(2) and MgCO3 were used as regeneration agents to regenerate the organic phase. The extraction efficiency of lithium ions remained at about 53% during reusing the organic phase ten times, demonstrating that the proposed extraction system had good stability and reusability.

The extensive use of fluoroquinolones antibiotics (FQs) makes great contributions to human society, but it also brings serious threats due to its stable chemical properties and difficulty in natural degradation. Since FQs can form stable chelates with polyvalent metal cations, the new adsorbents based on this chelating agent can not only remove FQs effectively, but also have the characteristics of selective identification on target pollutants. In this paper, novel sodium alginate-based gel spheres were prepared by droplet polymerization with sodium alginate (SA) as functional monomer, AlCl3/CaCl2 solutions and glutaraldehyde (GA) as crosslinking agents. The SA-Al/Ca gel spheres and GA (SA-Al/Ca) gel spheres were successively prepared for adsorption of levofloxacin (S-OFX) from aqueous solution. The results showed that after ion crosslinking with AlCl3/CaCl2 solutions and covalent crosslinking with GA, the prepared SA-Al/Ca and GA (SA-Al/Ca) gel spheres showed high adsorption capacity and good reusability, respectively. The equilibrium adsorption capacity of SA-Al/Ca gel spheres reached up to 176.26 mgL(-1) with the initial concentration of S-OFX as 100 mg.L-1. The maximum removal rate of SOFX was 92.10%. The GA (SA-Al/Ca) gel spheres had a certain degree of tolerance in temperature, pH, and ionic strength. The adsorption of S-OFX by both SA-Al/Ca and GA (SA-Al/Ca) gel spheres had fast kinetics. Moreover, the prepared GA (SA-Al/Ca) gel spheres also showed good reusability and stability.

Sodium phosphomolybdate with a spatial stereo symmetry structure and stability in acid and alkali was used as a new coextraction agent for separating Li+. In addition, methyl isobutyl ketone and tributyl phosphate were used as diluent and extractant, respectively. The influence of operation conditions on separation performance of lithium ion was investigated. The single stage extraction efficiency of Li+ was 58.74% with the volume fraction of tributyl phosphate, O/A phase ratio, and molar ratio of sodium phosphomolybdate to lithium as 40%, 3.6, and 1, respectively. Then the cross-flow and saturated extraction experiments were conducted. When 0.2 mol/L LiCl + 1.8 mol/L NaCl solution was used as washing agent and O/A phase ratio was 3, the washing efficiency of Mg2+ reached up to 99.59%. When 0.26 mol/L HCl solution was used as stripping agent and O/A phase ratio was 3, the stripping efficiency of Li+ reached 98.3%. The difference in extraction efficiency was within 6.5% through 10 recyclings of the organic phase, indicating that the coextraction agent was very stable. The extraction mechanism was investigated and the binding ability of P=O in tributyl phosphate molecule followed the sequence Li+ >> Na+ > K+ > Mg2+.

The aim of the study is to discriminate mono-floral honey by the chemical characteristics of non-sugar components (NSC) present in honey based on their botanical origin. The NSC in 50 honey samples including jujube, chaste and locust were determined and compared using HPLC and 1H-NMR combined with chemometrics analysis. The results showed that the content of NSC in jujube honey was the highest, with the average value of 780.77 mg/100 g, followed by locust honey, the lowest was chaste honey, with the average value of 292.43 mg/100 g. HPLC and 1H-NMR fingerprints of mono-floral honey samples were established, in which common chromatographic and spectral peak information were obtained. Principal component analysis and discrimination analysis were performed using selected common peaks as dependent variables and floral origin as independent variables, 44 honey samples and six test samples were correctly classified according to their floral origin.

A new type of Rb(I) ion imprinting material was prepared with methacrylic acid as functional monomer, Rb(I) ion as template, and methanol/acetonitrile as solvent. The polymerization reaction was initiated by N,N-azobis(isobutyronitrile) (AIBN) with the cross-linking by ethylene glycol dimethacrylate (EGDMA). In addition, benzo-12-crown-4-ether (B12C4) was introduced as a ligand to fix the template ions better. Scanning electron microscope, Zeta potential analysis, Fourier transform infrared spectrum, thermogravimetric analysis, and energy dispersive spectra were used for characterization of the imprinted polymer. Effects of preparation and adsorption conditions on adsorption performances of Rb(I) ion-imprinted polymers (IIPs) were investigated. The imprinted polymer had fast adsorption kinetics (reaching equilibrium within 15 min) and high maximum adsorption capacity (129.9 mg.g(-1)) at pH 9.5. Besides, the adsorption process conformed to pseudo-second-order kinetic and Freundlich isotherm models. Moreover, the prepared Rb(I)-IIPs showed high selectivity for Rb(1) ions. The results of eight repeated cycles of adsorption-desorption demonstrated that the prepared Rb(I)-IIPs had good stability and reusability.

为提升水资源配置效率,应用数据挖掘技术,对全国首次重点用水单位监控工作中所获得的约26万个用水数据进行了特征选择和用水模式区分.依据DB index准则,从用水特征中筛选出现状、愿景和波动3个特征.从这3个特征入手,采用k-means算法,将用水主体划分为5种用水模式,即均衡扩张型、均衡紧缩型、集中稳定型、波动收缩型和波动扩张型.结果 表明:全国大多数用水单位现状特征集中在[0.7,0.9]、愿景特征集中在[0.8,1.0]、波动特征集中在[0.1,0.5],较内地用水,东南沿海用水量在年内各月间波动较小.用水模式以波动收缩型为主,该模式涵盖多数产能过剩的高耗水行业;农业的用水模式为集中稳定型;高新技术与服务业的用水模式多为波动扩张型与均衡扩张型.结合不同的用水特征和用水模式,在法律、制度、监控等层面分别提出了管理建议,可为精准化、差异化节水管理提供参考.

A fluoride-free ionic liquid 1-butyl-3-methylimidazolium phosphotungstate ([Bmim]3PW12O40) was synthesized and first used as co-extraction reagent for recovery of lithium ions from salt lake brine with a high Mg/Li ratio. Fourier transform infrared spectra (FT-IR), nuclear magnetic resonance (NMR) and thermogravimetric analysis (TGA) were used for characterizations of the prepared ionic liquid. Tributyl phosphate (TBP), [Bmim]3PW12O40, and dimethyl phthalate (DMP) were used as extractant, co-extraction reagent, and diluent, respectively. Effects of molar ratio of [Bmim]3PW12O40 to Li+, O/A phase ratio, volume fraction of TBP,and carbon chain length of ionic liquid on extraction efficiency and separation factor of Li+ were investigated. The overall extraction efficiency of Li+ was 99.23% after five stages cross-current extraction experiments under optimal conditions. The washing and stripping experiments of the organic phase were conducted, and the parameters were optimized. The reusability of the organic ...

目的:优化红曲胞外多糖的提取工艺,首次探讨其对蛋白质氧化损伤的保护活性.方法:采用单因素实验和正交实验设计方法优化提取工艺;以2,2’-偶氮二异丁基脒二盐酸盐(2,2’-azobis2-methyl-propanimidamide,AAPH)作蛋白损伤诱导剂,采用凝胶电泳检测红曲多糖对蛋白损伤的保护活性.结果:单因素实验及正交实验得出,在以料液比1∶24(g∶mL),提取时间2h,提取温度100℃时,粗多糖的提取率为2.86％,含量为41.20％.抗氧化实验发现红曲多糖提取物对蛋白氧化损伤具有保护活性,其最小保护浓度为200 μg/mL.

蜂蜜是一种成分高度复杂的天然保健食品, 富含很多对人体有益的营养物质, 深受广大消费者青睐.蜂蜜成分易受蜜源种类、采蜜季节、贮藏时间等诸多因素影响.随着国内外消费者对蜂蜜需求的不断增大, 蜂蜜质量问题频繁出现, 如向蜂蜜中添加糖浆, 以杂花蜜或劣质蜜充当优质的单花蜜等, 严重影响蜂蜜市场的健康发展, 如何科学检测蜂蜜品质是目前我国乃至国际蜂业发展中亟待解决的关键问题.本文针对蜂蜜中的主要化学成分, 对现阶段国内外的蜂蜜真伪鉴别技术进行综述, 以期为准确、快速鉴别蜂蜜真伪的研究和应用提供参考.