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1.
The essential oils of hinoki (Chamaecyparis obtusa) leaves have anti-bacterial, anti-fungal, and relaxation properties that are likely associated with the major components such as sabinene, α-terpinyl acetate, limonene, elemol, myrcene, and hibaene. The present study describes the use of a cellulose-dissolving ionic liquid (IL) [C2mim][(MeO)(H)PO2] and low-toxicity solvents called betaine-based deep eutectic solvents (DESs) for the efficient extraction of hinoki essential oils. As a control method, organic solvent extraction was performed using either hexane, ethyl acetate (EtOAc), or acetone at 30 °C for 1 h. Both the experimental and control methods were conducted under the same conditions, which relied on partial dissolution of the leaves using the IL and DESs before partitioning the hinoki oils into the organic solvent for analysis. Quantitative analysis was performed using gas chromatography–mass spectrometry (GC-MS) in selected ion monitoring (SIM) mode. The results indicated that extraction using the [C2mim][(MeO)(H)PO2]/acetone bilayer system improved the yields of limonene and hibaene, 1.5- and 1.9-fold, respectively, when compared with the control method. In addition, extraction using betaine/l-lactic acid (molar ratio 1:1) gave the greatest yields for both limonene and hibaene, 1.3-fold and 1.5-fold greater, respectively, than when using an organic solvent. These results demonstrate the effective extraction of essential oils from plant leaves under conditions milder than those needed for the conventional method. The less toxic and environmentally begin DESs for the extraction are also applicable to the food and cosmetic industries.  相似文献   

2.
The ionic conductivity of the solutions formed from 1-n-butyl-3-methylimidazolium tetrafluoroborate ([Bmim][BF4]) or 1-n-butyl-3-methylimidazolium hexafluorophosphate ([Bmim][PF6]) and different molecular solvents (MSs) were measured at 298.15 K. The molar conductivity of the ionic liquids (ILs) increased dramatically with increasing concentration of the MSs. It was found that the molar conductivity of the IL in the solutions studied in this work could be well correlated by the molar conductivity of the neat ILs and the dielectric constant and molar volume of the MSs.  相似文献   

3.
周佳  禹洁  朱书强  邵永华  黄韡  祖新 《分析测试学报》2019,38(11):1358-1363
采用四丁基氯化铵和辛酸合成新型疏水性低共熔材料,并以其为萃取剂建立了快速测定饮料、配制酒中11种有机合成色素的高效液相色谱方法。样品经水稀释,以200μL低共熔溶剂萃取后,采用高效液相色谱-二极管阵列检测器(HPLC-DAD)检测,外标法定量。结果表明,11种有机合成色素在各自的质量浓度范围内均呈良好的线性关系,相关系数(r~2)均大于0.996,检出限为0.03~0.31 mg/kg,定量下限为0.08~1.02 mg/kg;加标回收率为92.6%~103%,相对标准偏差(RSD)为0.98%~4.3%。该方法快速、简便、精准,适用于饮料、配制酒中有机合成色素的检测。  相似文献   

4.
Microspheres were prepared using a hydrocarbon-perfluorocarbon solvent extraction process. The effect of the physical properties and the emulsification conditions on the mean microsphere size was investigated. The viscosity of the dispersed and the continuous phase greatly affected the microsphere size. Smaller microspheres were produced at the same mixing intensity when the viscosity of the dispersed phase decreased. Increased continuous phase viscosity reduced the coalescenceof the droplets and hence smaller microspheres were produced. The mean microsphere size first decreased as the volume ratio of the dispersed phase to the continuous phase increased but upon further increase the mean microsphere size increased. The effect of the volume ratio on the microsphere size was linked to the surfactant concentration. The stability of the studied hydrocarbon-in-fluorocarbon emulsion is poor. One reason for the poor stability is the high density difference between the phases. The emulsion droplets were solidified by siphoning part of the emulsion in the fresh continuous phase, which extracted the solvent from the dispersed phase. The effect of emulsion transfer time between the emulsification and solidification steps on the particle size was studied but no significant effect was observedduring the controlled time interval.  相似文献   

5.
范云场  张社利  陈梅兰  申屠超  朱岩 《分析化学》2010,38(12):1785-1788
以离子液体氯化1-辛基-3-甲基咪唑盐([Omim]Cl)的水溶液为萃取剂,采用加速溶剂萃取结合高效液相色谱法测定了蜜饯中苯甲酸、山梨酸、肉桂酸等有机酸类防腐剂,优化了加速溶剂萃取实验参数,最佳萃取条件为:离子液体浓度为0.1mol/L,萃取时间为5min,萃取温度为80℃。在最佳条件下,有机酸类防腐剂的检出限为0.4~27.7μg/L。将本方法用于蜜饯样品的检测,回收率为78.2%~113.9%。实验结果表明:离子液体-加速溶剂萃取法快速、高效。  相似文献   

6.
In this research, a process for developing normal-phase liquid chromatography solvent systems has been proposed. In contrast to the development of conditions via thin-layer chromatography (TLC), this process is based on the architecture of two hierarchically connected neural network-based components. Using a large database of reaction procedures allows those two components to perform an essential role in the machine-learning-based prediction of chromatographic purification conditions, i.e., solvents and the ratio between solvents. In our paper, we build two datasets and test various molecular vectorization approaches, such as extended-connectivity fingerprints, learned embedding, and auto-encoders along with different types of deep neural networks to demonstrate a novel method for modeling chromatographic solvent systems employing two neural networks in sequence. Afterward, we present our findings and provide insights on the most effective methods for solving prediction tasks. Our approach results in a system of two neural networks with long short-term memory (LSTM)-based auto-encoders, where the first predicts solvent labels (by reaching the classification accuracy of 0.950 ± 0.001) and in the case of two solvents, the second one predicts the ratio between two solvents (R2 metric equal to 0.982 ± 0.001). Our approach can be used as a guidance instrument in laboratories to accelerate scouting for suitable chromatography conditions.  相似文献   

7.
A vortex-assisted liquid-liquid microextraction, based on a natural hydrophobic deep eutectic solvent made from the monoterpene thymol and octanoic fatty acid, was employed for the analysis of 11 phthalate esters and one adipate in kombucha (a tea-based fermented beverage). Separation and determination were performed using an ultra-high performance liquid chromatography (UHPLC) system coupled to a single quadrupole mass spectrometer. Confirmatory analyses were carried out through UHPLC tandem mass spectrometry. The full method was validated in terms of matrix effect, matrix-matched calibration, sensitivity, recovery, limits of detection and quantification and repeatability. Satisfactory determination coefficients for quadratic calibration curves (≥0.9938), recovery values (67–120%) and limits of detection (0.07–5.45 µg/L) were obtained. Analysis of 26 kombucha samples reported concentrations for dibutyl phthalate and dimethyl phthalate in the range between the limit of quantification (LOQ) and 16.18 ± 1.14 µg/L, although these phthalates were also detected under the LOQ in some of the analyzed samples. Only one of the samples bottled in plastic containers (7) did not present residues while only five of the 19 samples in glass bottles contained any plasticizer. However, the highest concentration was found in a kombucha bottled in food-grade glass. This work represents the first application in which phthalates and adipates are analyzed in kombuchas.  相似文献   

8.
建立快速溶剂萃取–高效液相色谱法测定禽蛋中磺胺嘧啶残留的方法。用单因素和正交试验对禽蛋中磺胺嘧啶的萃取条件进行优化,确定了最佳萃取条件:以甲醇为萃取剂,在130℃循环萃取4次,冲洗体积分数为80%,萃取时间为25 min。色谱柱为Hypersil ODS2柱(4.6 mm×250 mm,5μm),流动相为甲醇–0.5%冰乙酸(25∶75),流量为1.0 m L/min,检测波长为265 nm。磺胺嘧啶的质量浓度在0.025~0.500 mg/m L范围内与色谱峰面积呈良好的线性关系,相关系数r=0.999 5,检出限为0.5μg/kg。加标回收率在83.0%~88.2%之间,测定结果的相对标准偏差为2.2%(n=9)。方法的精密度、准确度和基质效应均符合禽蛋样品检测要求,可用于禽蛋中磺胺嘧啶含量的测定。  相似文献   

9.
Recovery of platinum group metals from spent materials is becoming increasingly relevant due to the high value of these metals and their progressive depletion. In recent years, there is an increased interest in developing alternative and more environmentally benign processes for the recovery of platinum group metals, in line with the increased focus on a sustainable future. To this end, ionic liquids are increasingly investigated as promising candidates that can replace state-of-the-art approaches. Specifically, phosphonium-based ionic liquids have been extensively investigated for the extraction and separation of platinum group metals. In this paper, we present the extraction capacity of several phosphonium-based ionic liquids for platinum group metals from model deep eutectic solvent-based acidic solutions. The most promising candidates, P66614Cl and P66614B2EHP, which exhibited the ability to extract Pt, Pd, and Rh quantitively from a mixed model solution, were additionally evaluated for their capacity to recover these metals from a spent car catalyst previously leached into a choline-based deep eutectic solvent. Specifically, P66614Cl afforded extraction of the three target precious metals from the leachate, while their partial separation from the interfering Al was also achieved since a significant amount (approx. 80%) remained in the leachate.  相似文献   

10.
Blueberry wine residues produced during the wine-brewing process contain abundant anthocyanins and other bioactive compounds. To extract anthocyanins from blueberry wine residues more efficiently, a novel procedure of ultrasound-assisted deep eutectic solvent extraction (UADESE) was proposed in this work. The extraction process was optimized by response surface methodology coupled with genetic algorithm. The optimum extraction parameters to achieve the highest yield of anthocyanins (9.32 ± 0.08 mg/g) from blueberry wine residues by UADESE were obtained at water content of 29%, ultrasonic power of 380 W, extraction temperature of 55 °C, and extraction time of 40 min. The AB-8 macroporous resin combined with Sephadex LH-20 techniques was used to purify the crude extract (CE) obtained under optimum extraction conditions and analyze the anthocyanins composition by HPLC-ESI-MS/MS. The cyanidin-3-rutinoside with purity of 92.81% was obtained. The HepG2 antitumor activity of CE was better than that of the purified anthocyanins component. Moreover, CE could increase the intracellular reactive oxygen species levels and the apoptosis, and arrest HepG2 cells in the S phases. These findings provided an effective and feasible method for anthocyanins extraction, and reduced the environmental burden of this waste.  相似文献   

11.
Liquid-liquid extractive-spectrophotometric studies of sodium ion complexes of 18-crown-6(18C6), dibenzo-18-crown-6(DB18C6), 15-crown-5(15C5), and 12-crown-4(12C4) and anionic dyes [4-(2-pyridylazo)-resorcinol monosodium salt monohydrate (PAR), Eriochrom Black T (EBT), and methyl orange (MOR)] and sodium picrate (PICRAT) as the counter ion are described. The overall extraction equilibrium constants for the 1 : 1 complexes of the above crown ethers with sodium dyes between different organic solvents and water have been determined at 25deg;C. They were conducted in various solvent-water systems maintaining an identical initial cation concentration in water, [M0+]w, and macrocyclic ligand concentration in the organic phase, [L0]org}, so that in all extractions [M0+]w : [L0]org ratios were 1 : 1, 1 : 10, 1 : 20, 1 : 50, and 1 : 62.5. An ion association complex formed between the sodium-crown ether complex ion and a dye anion was extracted into the organic solvent, and then the dye concentration of the separated aqueous phase was measured with an ultraviolet-visible spectrophotometer. PAR was the best associated dye with all crown ethers sodium-dyes and the extracted dye occurs as the ion-pair complex. Methylene chloride was found to be better than other extractive solvents used in this study.  相似文献   

12.
离子液体提取分离鹿藿中异黄酮化合物   总被引:6,自引:1,他引:5  
以1-丁基-3-甲基咪唑四氟硼酸盐([Bmim]BF4)离子液体取代天然产物研究中的溶剂,对具有抗雄性生育活性和抑菌作用的鹿藿根中的异黄酮成分进行提取和分离。 从鹿藿根的70%乙醇粗提物中,成功分离纯化得到3种异黄酮类化合物,它们均是首次从植物鹿藿中分离得到。 经过波谱分析鉴定,3种化合物的结构被确定为木豆酮(Cajanone)、鸡豆黄素A(Biochanin A)和1种新的异黄酮类化合物,被命名为3-[4′-(1″-甲氧基)-丙基氧代]-苯基-5,7-二羟基异黄酮(3-[4′-(1″-methoxy)propoxy]-phenyl-5,7-dihydroxy-isoflavone)。 建立了植物鹿藿中异黄酮含量的测定方法:以木豆酮化合物为标准品,在其紫外最大吸收峰270 nm处,测得生药中总异黄酮的含量为0.73%;测得平均加样回收率99.94%,相对标准偏差3.66%,离子液体回收率76.7%。  相似文献   

13.
基于小分子醇双水相体系和离子液体双水相体系,建立了正丙醇与亲水性离子液体1-丁基-3-甲基咪唑四氟硼酸[Bmim]BF4和(NH4)2SO4形成的二元双水相体系萃取盐酸多西环素的新方法。考察了(NH4)2SO4含量、正丙醇用量、pH值、离子液体含量以及盐酸多西环素含量对盐酸多西环素分配行为的影响。结果表明:当醇和离子液体二元双水相体系的pH值在4.0~5.0范围内,(NH4)2SO4含量为34%,且盐酸多西环素的质量浓度在25~95 mg/L之间时,该体系对盐酸多西环素的萃取率可达90.26%~95.71%,分配系数可达62.452~149.401。  相似文献   

14.
选用非质子型有机溶剂聚乙二醇二甲醚(NHD)与N, N-二甲基乙酰胺(DMAC), 分别与BmimFeCl4复配, 构建了BmimFeCl4/NHD和BmimFeCl4/DMAC复合铁基离子液体体系. 考察了温度、 BmimFeCl4/溶剂的质量 比以及压力对CO2在复合铁基离子液体体系中溶解行为的影响. 结果表明, 高压低温的吸收条件更利于CO2 的溶解, 当BmimFeCl4/DMAC质量比为7∶3时, CO2在BmimFeCl4/DMAC复合体系中的亨利系数为0.9181 MPa·L·mol-1, 低于同等条件下BmimFeCl4/NHD体系的亨利系数. 在常压、 363.2 K条件下进行再生, 经5次循环后, CO2在BmimFeCl4/NHD和BmimFeCl4/DMAC中的溶解度分别为初次吸收量的92.53%和99.04%. 傅里叶变换红外光谱(FTIR)结果表明, 铁基离子液体复配体系吸收CO2为物理吸收过程. 密度泛函理论(DFT)计算与IRI分析的结果表明, 在复配DMAC的体系中, CO2更倾向与阳离子和溶剂分子作用, 而在复配NHD的体系中, CO2则更容易与阴离子和溶剂分子作用.  相似文献   

15.
用微波辐射法,合成了5个含有机膦氧基团的离子液体:1-丙基-3-(3-二苯基氧膦基)丙基咪唑双(三氟甲基磺酰基)亚胺盐([PImC3P(O)Ph2][Tf2N])、1-己基-3-(3-二苯基氧膦基)丙基咪唑双(三氟甲基磺酰基)亚胺盐([HImC3P(O)Ph2][Tf2N])、1-丙基-3-(3-苯基乙氧基氧膦基)丙基咪唑双(三氟甲基磺酰基)亚胺盐([PImC3P(O)Ph(OEt)][Tf2N])、1-己基-3-(3-苯基乙氧基氧膦基)丙基咪唑双(三氟甲基磺酰基)亚胺盐([HImC3P(O)Ph(OEt)][Tf2N])和(3-苯基乙氧基氧膦基)丙基三乙胺双(三氟甲基磺酰基)亚胺盐([TENC3P(O)Ph(OEt)][Tf2N])。 用31P NMR、1H NMR、13C NMR、MS及FT-IR对产物结构进行了表征。 研究了这类离子液体对稀土Nd(III)的萃取性能。 结果表明,这类功能化离子液体可作为单一组分萃取稀土而无需加入有机稀释剂,离子液体结构对萃取效率影响很大,相同条件下季铵盐型结构的离子液体[TENC3P(O)Ph(OEt)][Tf2N]对稀土Nd(Ⅲ)的萃取效率最高。 稀土溶液pH值对萃取效率影响显著,近中性条件下(pH=6.63),对稀土Nd(Ⅲ)的萃取率最高。 用pH=1.00的盐酸溶液可以较好的从离子液体相反萃Nd(Ⅲ),反萃率可达94%。  相似文献   

16.
0 Introduction Titania has been extensively used in a variety of applications such as gas sensors, dielectric ceram ics, catalysts for therm al or photoinduced processes, pho- tovoltaic solar cells, and pigm ents. One of the m ost im portant applications …  相似文献   

17.
舒庆  杨伯伦  王福安 《结构化学》2005,24(9):1083-1087
1 INTRODUCTION As a new generation of solvent and catalyst, ionic liquid has captured intensive attention in the field of green chemistry[1, 2]. The most significant physical character is that its property can be changed with different choices of anions, cations and substituents. For example, the water solubility can be altered by choosing proper substituent on cation, and decreased by increasing the length of alkyl chain. On the other hand, critical change of its physical properties can …  相似文献   

18.
研究了疏水性离子液体[BMIM][PF6]对脂肪酶R. miehei有机相催化合成辛酸戊酯反应的影响,并结合荧光发射光谱分析R. miehei构象变化与酶活性表达的关联。结果表明,该酯化反应在饱和烷烃中的初速度比在芳烃中的大,且当溶剂logP为1.5~3.5时,反应初速度随logP的增加而降低。在不同有机溶剂中,加入占辛酸质量1%的[BMIM][PF6]均导致反应初速度降低15%左右,降低幅度几乎不与溶剂种类有关。表明[BMIM][PF6]对该反应的影响与所在溶剂系统无关,而只与离子液体的加入有关。[BMIM][PF6]加入量为辛酸质量1%~3%时,以壬烷为溶剂时的反应初速度随[BMIM][PF6]加入量的增加而降低,进一步表明离子液体的加入量是影响反应初速度的重要因素。荧光光谱分析表明,酶活性的表现与酶分子的构象变化有一定的相关性。  相似文献   

19.
赵利萍  王震  董献堆 《应用化学》2018,35(2):216-223
利用1-乙基-3-甲基咪唑溴盐(EMIMBr)、1-己基-3-甲基咪唑溴盐(HMIMBr)、双三氟甲烷磺酰亚胺锂(LiTFSI)以及1-乙基-3-甲基咪唑氯盐(EMICl)和双氟磺酰亚胺钾(KFSI)制备了1-乙基-3-甲基咪唑双三氟甲磺酰亚胺盐(EMITFSI)、1-己基-3-甲基咪唑双三氟甲磺酰亚胺盐(HMITFSI)和1-乙基-3-甲基咪唑鎓二(氟甲磺酰基)亚胺盐(EMIFSI)3种离子液体。 用氯苯稀释的离子液体对钙钛矿活性层进行浸泡处理,探究了离子液体对钙钛矿形貌以及钙钛矿太阳能电池性能的影响。 结果表明,HMITFSI处理后太阳能电池的填充因子从0.71提高到了0.74,光电转换效率也有了一定提高,钙钛矿薄膜的表面形貌得到了改善,而EMITFSI和EMIFSI的处理反而降低了钙钛矿太阳能电池的性能,证实离子液体可以影响钙钛矿的结晶形貌。  相似文献   

20.
建立了液液萃取/高效液相色谱法测定豆干和腐竹中溶剂黄2和溶剂黄56的分析方法。样品经乙腈饱和的正己烷提取后,加入正己烷饱和的乙腈萃取,将乙腈层转入浓缩瓶内,重复萃取3次,将萃取液浓缩后用乙腈定容。采用Agilent TC-C18(4.6 mm×250 mm,5μm)色谱柱对样品进行分离;柱温为30℃;流动相为水-甲醇(20∶80);流速为1.0 m L/min;检测波长为410 nm。溶剂黄2和溶剂黄56在0.30~50 mg/L浓度范围内线性关系良好,其检出限(LOD)和定量下限(LOQ)分别均为0.15 mg/kg和0.50 mg/kg,方法的平均回收率为85.4%~94.6%,相对标准偏差(RSD,n=6)为0.3%~2.3%。该方法重复性好,灵敏度高,适用于豆干和腐竹中溶剂黄2和溶剂黄56含量的测定。  相似文献   

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