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1.
The aim of this work was to evaluate the influence of US on the properties of the fluconazole emulsions prepared using imidazolium-based ILs ([Cn C1im]Br). The effects of the preparation method (mechanical stirring or US), US amplitude, alkyl chain length (of [C12C1im]Br or [C16C1im]Br), and IL concentration on the physicochemical properties were evaluated. Properties such as droplet size, span index, morphology, viscosity encapsulation efficiency, and drug release profile were determined. The results showed that US-prepared emulsions had a smaller droplet size and smaller polydispersity (Span) than those prepared by mechanical stirring. Additionally, the results showed that emulsions prepared with [C16C1im]Br and US had spherical shapes and increased stability compared to emulsions prepared by MS, and also depended on the IL concentration. The emulsion prepared by US at 40% amplitude had increased encapsulation efficiency. US provided a decrease in the viscosity of emulsions containing [C12C1im]Br; however, in general, all emulsions had viscosity close to that of water. Emulsions containing [C16C1im]Br had the lowest viscosities of all the emulsions. The emulsions containing the IL [C16C1im]Br had more controlled release and a lower cumulative percentage of drug release. The IL concentration required to prepare these emulsions was lower than the amount of conventional surfactant required, which highlights the potential synergic effects of ILs and US in preparing emulsions of hydrophobic drugs.  相似文献   
2.
Ionic liquid functional MCM-41 was synthesized, characterized and used as heterogeneous catalyst for the Knoevenagel condensation of isatins with malononitrile. A series of corresponding isatylidene malononitrile were obtained in high isolated yield (96–99%) at room temperature in a short time. The heterogeneous catalyst can be easily recovered by centrifugation and showed almost no loss of activity over 10 recycle experiments. At the same time, the gram-scale experiments showed excellent yields and provided a highly effective method for scale up applications.  相似文献   
3.
The first principle computational screening was performed to investigate the effect of selected dopants for Li3PS4 sulfide solid electrolyte on its ionic conductivity and stability toward moisture. The results suggest that substitution P5+ using isovalent cations whose electronegativity (EN) value is closer to the value of S has more significant effects on the ionic conductivity, whereby W5+ and Sb5+ can improve most. Similarly, aliovalent cation substitutions with compensating changes in the lithium-ion concentration, particularly those with a lower oxidation state and higher EN, such as Cu2+, effectively enhance the lithium-ion conductivity in this structure. For cation dopants, it is found that ionic conductivity improvement of Li3PS4 is the synergetic effect of EN and oxidation number of the dopant as well as the material's lattice parameter change. Oxides of the considered cation dopants can also improve the ionic conductivity of the material but have much lower lithium-ion conductivity than the cases of cation dopants. However, the metal oxide dopants, particularly those derived from soft Lewis' acid cations, show a marginal improvement in moisture stability of the Li3PS4 electrolyte. The effect of halides and metal halide dopants on the lithium-ion conductivity and moisture stability of Li3PS4 electrolyte are also studied. It is found that metal halides are more effective than any other dopants in improving the ionic conductivity of Li3PS4.  相似文献   
4.
Despite previous reports showing that crystallization kinetics affects zeolite phase selectivity because zeolites are metastable species in their synthesis solution rather than thermodynamic end points, the critical kinetics-controlling parameter is yet to be determined. This work elucidated the effect of tetraethyl orthosilicate (TEOS) hydrolysis before hydrothermal treatment on the final zeolite phase selectivity in the ionic liquid-templated synthesis of 10-membered ring zeolites (MFI- or TON-type zeolites). The results showed that the dissolved silica concentration in the synthesis solution, which is controlled by varying the TEOS hydrolysis temperature and addition rate, induced heterogeneous nuclear growth. Specifically, in 1-butyl-3-methylimidazolium ([BMIM]Br)-directed syntheses, the high and low concentrations of dissolved silica species led to MFI and TON zeolite formation, respectively. The experimental results are supported by silica polymerization modeling using the Reaction Ensemble Monte Carlo method and theoretical calculations on composite building unit formation. The results are valuable for understanding the nucleation mechanism in zeolite crystallization.  相似文献   
5.
This study investigates the potential of using small amounts of ionic liquids (IL) to enhance ultrasound-assisted extraction of lipids content from green microalgae. Three imidazolium-based ILs (butyl, octyl and dodecyl), each of them with two anions (bromide and acetate) were tested as additives. Viscosity and surface tension of the ILs aqueous mixtures were analyzed to determine the influence of ILs’ anions and alkyl chain length, whereas KI dosimetry experiments were used as an indicator of radicals formation. A key finding suggests that the small addition of ILs improves the ultrasonication either by enhancing the viscosity and reducing the water surface tension, leading to a more powerful acoustic cavitation process or by increasing HO° production likely to oxidize the microalgae cells membranes, and consequently disrupting them on a more efficient manner. KI dosimetry also revealed that long ILs alkyl chain is detrimental. This experimental observation is confirmed thus strengthened as the yield of extracted lipids from green microalgae has shown an incremental trend when the IL concentration also increased. These hypotheses are currently under investigation to spot detailed impact of ILs on cavitation process.  相似文献   
6.
Recently, efficient extraction of natural products from traditional Chinese medicines (TCMs) by green solvents is deemed an essential area of green technology and attracts extensive attentions. In this work, a green protocol for simultaneous ultrasonic-extraction of the native compounds with different polarities of TCMs by using a hybrid ionic liquids (HILs)-water system was reported for the first time. As a case study, three superior ILs (1-ethyl-3-methylimidazolium tetrafluoroborate ([EMIM][BF4]), 1-ethyl-3-methylimidazolium acetate ([EMIM][OAc]), and 1-allyl-3-methylimidazolium chloride ([AMIM]Cl)) were chosen as the compositions of the HILs system, and the TCMs Suhuang antitussive capsule (SH) containing different-polarity lignans was selected. Primarily, an ultra-performance liquid chromatography coupled to triple quadrupole tandem mass spectrometry (UPLC-QqQ-MS/MS) method in the multiple reaction monitoring (MRM) mode was established for qualitative and quantitative analysis of 18 lignans. After majorization by uniform design experiment, the HILs prepared with [AMIM]Cl, [EMIM][BF4], and [EMIM][OAc] at a volume ratio of 1:5:5 could simultaneously extract multi-polarity lignans compared to single IL. Subsequently, the conditions of ultrasonic extraction employing with HILs and traditional organic solvent were optimized by the response surface methodology, respectively. The results indicated that the extract efficiency of the HILs system for target compounds was significantly improved compared with the traditional organic solvent-extraction, i.e. the content of total lignans in ethanol system was up to 47 mg/g, while that in the HILs system was up to 69 mg/g, with an increasing of 47%. Additionally, 1H-NMR and 13C-NMR spectra were used to characterize the hydrogen-bond interactions in the HILs-lignan mixtures. Extraction with the HILs in TCMs is a new application schema of ILs, which not only avoids the use of volatile toxic organic solvents, but also shows the potential to be comprehensively applied for the extraction of bioactive compounds from TCMs.  相似文献   
7.
Solid-state lithium batteries (SSLBs) have been identified as one kind of the most promising energy conversion and storage devices because of their safety, high energy density, and long cycling life. The development of solid-state electrolyte is vital to commercialize SSLBs. Composite polymer electrolyte (CPE), derived by compositing inorganic particles into solid polymer electrolyte has become the most practical species for SSLBs because it inherits the advantages of polymer electrolyte and simultaneously achieves enhanced ionic conductivity and mechanical properties. The characteristics of inorganic particles and their interaction with polymers strongly impact the performance of CPE, improving its ionic conductivity, mechanical properties, thermal and electrochemical stability, as well as interface compatibility with both electrodes. In this review, the effects of particle characteristics including its species, size, proportion, morphology on the ionic conductivity and mechanical properties of CPE are reviewed. Meanwhile, some novel composite strategies are also introduced including surface modification, hybridization, and alignment of particles in polymer matrices, as well as some new preparation methods of CPE. The interactions between particles and other components in CPE including polymer matrices or lithium salt are particularly focused herein to reveal the lithium conductive mechanism. Finally, a perspective on the direction of future CPE development for SSLBs is presented.  相似文献   
8.
Selection of affinity ligands for protein targets from oligonucleotide libraries currently involves multiple rounds of alternating steps of partitioning of protein‐bound oligonucleotides (binders) from protein‐unbound oligonucleotides (nonbinders). We have recently introduced ideal‐filter capillary electrophoresis (IFCE) for binder selection in a single step of partitioning. In IFCE, protein‐binder complexes and nonbinders move inside the capillary in the opposite directions, and the efficiency of their partitioning reaches 109, i.e., only one of a billion molecules of nonbinders leaks through IFCE while all binders pass through. The condition of IFCE can be satisfied when the magnitude of the mobility of EOF is smaller than that of the protein‐binder complexes and larger than that of nonbinders. The efficiency of partitioning in IFCE is 10 million times higher than those of solid‐phase‐based methods of partitioning typically used in selection of affinity ligands for protein targets from oligonucleotide libraries. Here, we provide additional details on our justification for IFCE development. We elaborate on electrophoretic aspects of the method and define the theoretical range of EOF mobilities that support IFCE. Based on these theoretical results, we identify an experimental range of background electrolyte's ionic strength that supports IFCE. We also extend our interpretation of the results and discuss in‐depth IFCE's prospective in practical applications and fundamental studies.  相似文献   
9.
The sphene-type solid electrolyte with high ionic conductivity has been designed for solid-state lithium metal battery. However, the practical applications of solid electrolytes are still suffered by the low relative density and long sintering time of tens of hours with large energy consumption. Here, we introduced the spark plasma sintering technology for fabricating the sphene-type Li1.125Ta0.875Zr0.125SiO5 solid electrolyte. The dense electrolyte pellet with high relative density of ca. 97.4% and ionic conductivity of ca. 1.44×10-5 S/cm at 30℃ can be obtained by spark plasma sintering process within the extremely short time of only ca. 0.1 h. Also the solid electrolyte provides stable electrochemical window of ca. 6.0 V(vs. Li+/Li) and high electrochemical interface stability toward Li metal anode. With the enhanced interfacial contacts between electrodes and electrolyte pellet by the in-situ formed polymer electrolyte, the solid-state lithium metal battery with LiFePO4 cathode can deliver the initial discharge capacity of ca. 154 mA·h/g at 0.1 C and the reversible capacity of ca. 132 mA·h/g after 70 cycles with high Coulombic efficiency of 99.5% at 55℃. Therefore, this study demonstrates a rapid and energy efficient sintering strategy for fabricating the solid electrolyte with dense structure and high ionic conductivity that can be practically applied in solid-state lithium metal batteries with high energy densities and safeties.  相似文献   
10.
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