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In NH3 capture technologies, the desorption process is usually driven by high temperature and low pressure (such as 150–200 °C under vacuum), which accounts for intensive energy consumption and CO2 emission. Developing light responsive adsorbent is promising in this regard but remains a great challenge. Here, we for the first time designed and synthesized a light responsive azophenol‐containing covalent organic framework (COF), COF‐HNU38, to address this challenge. We found that at 25 °C and 1.0 bar, the cis ‐COF exhibited a NH3 uptake capacity of 7.7 mmol g−1 and a NH3/N2 selectivity of 158. In the adsorbed NH3, about 29.0 % could be removed by vis‐light irradiated cis‐trans isomerization at 25 °C, and the remaining NH3 might be released at 25 °C under vacuum. Almost no decrease in adsorption capacity was observed after eight adsorption‐desorption cycles. As such, an efficient NH3 capture and low energy release strategy was established thanks to the multiple hydrogen bond interactions (which are strong in total but weak in individuals) between NH3 and the smart COF, as well as the increased polarity and number of hydrogen bond sites after the trans‐cis isomerization. [ABSTRACT FROM AUTHOR]

In recent years, light‐responsive molecules have been incorporated in metal–organic frameworks (MOFs) to fabricate light‐responsive intelligent devices, where reversible isomerization of the guest molecules in the nanopores is crucial. However, how to design a porous environment of MOFs to achieve a reversible isomerization remains unknown until now. In this work, donor–acceptor Stenhouse adducts (DASAs), a new kind of visible light responsive compound, were confined in the nanopores of different MOFs to study their isomerization upon visible‐light irradiation/mild heating. We found that the polarity of the pore environment is the key to control the reversibility of isomerization of such guest molecules. Under the guidance of this principle, MIL‐53(Al) was screened to investigate the proton conductivity and switching performance of the DASA‐confined MOF. The proton conductance was up to 0.013 S cm−1 at 80 °C and 98 % RH, and at least 30 switching cycles were achieved thanks to the Grotthuss‐type mechanism and the low polarity of MIL‐53(Al) pore environment. [ABSTRACT FROM AUTHOR]

Utilizing weak interactions to effectively recover and separate precious metals in solution is of great importance but the practice remains a challenge. Herein, we report a novel strategy to achieve precise recognition and separation of gold by regulating the hydrogen‐bond (H‐bond) nanotrap within the pore of covalent organic frameworks (COFs). It is found that both COF‐HNU25 and COF‐HNU26 can efficiently capture AuIII with fast kinetics, high selectivity, and uptake capacity. In particular, the COF‐HNU25 with the high density of H‐bond nanotraps exhibits an excellent gold uptake capacity of 1725 mg g−1, which is significantly higher than that (219 mg g−1) of its isostructural COF (COF‐42) without H‐bond nanostrap in the pores. Importantly, the uptake capacity is strongly correlated to the number of H‐bonds between phenolic OH in the COF and [AuCl4]− in water, and multiple H‐bond interactions are the key driving force for the excellent gold recovery and reusability of the adsorbent. [ABSTRACT FROM AUTHOR]

Ionic liquids (ILs) have been used for carbon dioxide (CO2) capture, however, which have never been used as catalysts to accelerate CO2 capture. The record is broken by a uniquely designed IL, [EMmim][NTf2]. The IL can universally catalyze both CO2 sorption and desorption of all the chemisorption‐based technologies. As demonstrated in monoethanolamine (MEA) based CO2 capture, even with the addition of only 2000 ppm IL catalyst, the rate of CO2 desorption—the key to reducing the overall CO2 capture energy consumption or breaking the bottleneck of the state‐of‐the‐art technologies and Paris Agreement implementation—can be increased by 791% at 85 °C, which makes use of low‐temperature waste heat and avoids secondary pollution during CO2 capture feasible. Furthermore, the catalytic CO2 capture mechanism is experimentally and theoretically revealed. [ABSTRACT FROM AUTHOR]

Designing highly active and durable electrocatalysts remain an ongoing challenge in the oxygen reduction reaction (ORR). Here, the reductive IL/Ti3C2Tx(FA) is produced in a water‐free mixture of formic acid (FA), ionic liquid (IL) and LiF, subsequently, the simultaneous reduction encapsulation trap the Pd nanocatalysts and IL within bilayer carbide‐derived carbon (CDC) to obtain Pd@IL/CDC(FA) with high metal loading up to 69.7%. Thereby, the featured active phases in Pd@IL/CDC(FA) impart potent chemical nanoconfinement to defend metals from dissolution and aggregation, boost mass and electron transfer, and mediate oxidation states and adsorption/desorption of metal Pd in the ORR. Instead of deactivation and Ostwald ripening, the catalytic performances of Pd@IL/CDC(FA) are gradually enhanced in an accelerated durability test up to 20 000 cycles. In a Zn–air battery, the Pd@IL/CDC(FA) cathode gives a specific capacity of 812.6 mAh gZn−1 and a voltage loss of only 41 mV in galvanostatic discharge for 1000 h. The work opens new venues in controllably preparing high activity and durable electrocatalysts from in‐situ generated CDCs. [ABSTRACT FROM AUTHOR]

Ammonia (NH3) is an important chemical raw material and a unique carbon‐free fuel with high hydrogen energy density. Thus, NH3 capture, storage, and desorption are of significant importance. However, high capacity capture, low energy desorption, and selective separation of NH3 are still challengs so far. Here, we report high‐performance hybrid sorbents by anchoring LiCl in the nanopores of MIL‐53‐(OH)2 metal–organic frameworks (MOFs). It is found that the optimal composite shows a capture capacity of 33.9 mmol g−1 NH3 at 1.0 bar and 25 °C, which far exceeds the current record among the reported porous materials. Notably, the excellent capture capacity at low pressure and high temperature makes it possible to selectively capture NH3 from NH3/N2, NH3/CO2, and NH3/H2O. It is revealed that synergistic action of NH3 coordination to the highly dispersed Li+ in the MOF nanopores and hydrogen bonding of NH3 with Cl− account for such an excellent capture and selectivity performance. [ABSTRACT FROM AUTHOR]

Copper‐coordinated catalysts are reported to be effective for electrocatalytic CO2 reduction reaction (CO2RR) to C2 products but suffer from low selectivity. Herein a strategy was developed to tune the d‐band structure of CuII via coordinating with aromatic ligands to form Cu‐based conjugated polymers for CO2RR to C2 chemicals. The catalysts derived from copper chloride coordinating with tetraminobenzoquinone (TABQ) and with 1,2,4,5‐benzenetetramine possessed high‐density and compact Cu single‐atom sites and displayed high activity for CO2RR to C2 products. Especially, Cu‐TABQ exhibited a maximum C2 faradaic efficiency of 63.2 % with a current density of 423 mA cm−2 at −1.17 V (vs. reversible hydrogen electrode). Density functional theory calculations indicated that the TABQ linker possessing C=O groups significantly widened the d‐band of coordinated CuII, which facilitated binding of *CO intermediate on the catalyst and thus enhanced C−C coupling. This work provides mechanistic insight into the CuII‐coordinated polymers for CO2RR with high selectivity toward C2 products. [ABSTRACT FROM AUTHOR]

Supercapacitors (SCs) are fascinating energy storage devices due to their delivery of exceptional power density and long cycling stability. Unfortunately, their practical applications are still impeded by relatively inferior energy density, which is proportional to the square of the operating voltage of SCs. Ionic liquid (IL) electrolytes have a wide electrochemical stability window and thus can be used to significantly increase the energy density of SCs. The introduction of redox active species into IL‐based electrolytes effectively contributes to pseudocapacitance. Accordingly, IL‐based redox active electrolytes (IL‐REs) for SCs are springing up rapidly in recent years. This review provides an overall insight into various IL‐REs, including the ILs mixed with other redox active species, the ILs possessing redox active groups themselves, and the IL‐based redox gel polymer electrolytes for SCs. The basic understanding of IL electrolytes and IL‐REs is introduced and discussed as well as the application of the IL‐REs in SCs. Then, the energy storage mechanisms of these IL‐REs are discussed, and finally, current challenges and perspectives are highlighted for future research in this promising field. [ABSTRACT FROM AUTHOR]

Fluorescent single crystals that respond to multiple external stimuli are of great interest in molecular machines, sensors, and displays. The integration of photo‐ or acid‐induced fluorescence enhancement and bending in one organic crystal, however, has not been reported yet. Herein, we report the interesting plastic photomechanical bending and switching on of the fluorescence of an azine crystal in a single‐crystal transformation, due to extended π‐conjugation and molecular slippage. Moreover, the fluorescent plastic bending driven by multiple volatile acid vapors was firstly observed, and attributed to the synergistic effect of push–pull electronic structure and hydrogen bonding. The single crystal also shows high elasticity under external force. In addition, reversible fluorescence switching can be triggered by grinding and solvent fuming, as well as by the adsorption and desorption of HCl vapor. The integration of plastic, elastic bending and switch‐on fluorescence into one single crystal provides a new strategy for next‐generation smart materials. [ABSTRACT FROM AUTHOR]

As an important member of crystalline porous polymers, acylhydrazone‐linked covalent organic frameworks (COFs) have gained much attention in recent years. However, the low structural stability imparts a limit on their practical applications. To tackle this problem, we report a simple strategy to increase the chemical stability of acylhydrazone‐linked COFs by incorporating azobenzene groups in the conjugated framework. Through reinforcing the π‐π stacking interactions between the adjacent layers with increased π‐surface, it is surprising to find that the resulting materials exhibit extreme stability in harsh environments, such as in strong acid, strong base, aqueous educing agent and boiling water, even exposed to air for one year. As a proof‐of‐concept, such frameworks have been used to remove various organic micropollutants such as antibiotics, plastic components, endocrine disruptors, and carcinogens from water with high capacity, fast speed and excellent reusability over a wide pH range at environmentally relevant concentrations. The results provide a new avenue to significantly enhance the stability of COFs for practical applications. [ABSTRACT FROM AUTHOR]

Pickering emulsions are an excellent platform for interfacial catalysis. However, developing simple and efficient strategies to achieve product separation and catalyst and emulsifier recovery is still a challenge. Herein, we report the reversible transition between emulsification and demulsification of a light‐responsive Pickering emulsion, triggered by alternating between UV and visible light irradiation. The Pickering emulsion is fabricated from Pd‐supported silica nanoparticles, azobenzene ionic liquid surfactant, n‐octane, and water. This phase behavior is attributed to the adsorption of azobenzene ionic liquid surfactant on the surface of the nanoparticles and the light‐responsive activity of ionic liquid surfactant. The Pickering emulsion can be used as a microreactor that enables catalytic reaction, product separation as well as emulsifier and catalyst recycling. Catalytic hydrogenation of unsaturated hydrocarbons at room temperature and atmospheric pressure has been performed in this system to demonstrate product separation and emulsifier and catalyst re‐use. [ABSTRACT FROM AUTHOR]

Aggregation‐induced emission (AIE) materials have drawn great attention for applications as organic light‐emitting diodes (OLED) and probes. The applications are, however, restricted by the complex syntheses and hydrophobic properties. Herein, a one‐step synthesis of an AIE material based on imidazole hydrazone is assessed. Protonation of the imidazole‐H leads to emission color change from yellow to green in the solid state. The emission color is recovered upon imidazole‐H+ deprotonation. Moreover, the emission wavelength shifts from 532 to 572 nm by anion exchange. In addition, an enhanced emission (ΦF up to 22.6 %) was obtained with the Br− anion compared with NTf2−, SbCl5−, PF6−, and OTf− anions. X‐ray crystallography studies together with theoretical calculations show that the enhanced emission of hydrazone salts arises from strong hydrogen bonding between the hydrazone proton and the halide ion (Cl− or Br−). [ABSTRACT FROM AUTHOR]

The conversion of CO2 into valuable chemicals is an ideal pathway for CO2 utilization in industry, although the development of highly efficient catalysts remains a challenge. Herein, the design and synthesis of two covalent organic frameworks (COFs) functionalized with imidazolium salts were reported as catalysts for CO2 conversion. The resultant COFs possessed highly crystalline structures, showed high stability and surface area, and contained dense catalytic active sites on the pore walls. They exhibited outstanding catalytic performances for the reaction of CO2 with epoxides without any solvent or cocatalyst under mild conditions and afforded a record turnover number of 495 000. In addition, the COFs could serve as effective catalysts in the reductive reaction of CO2 with amines. The results presented here thus demonstrate the exceptional potential of the functionalized COFs for various challenging CO2 transformations. [ABSTRACT FROM AUTHOR]

The water content is crucial to the preparation of [P4442][Suc] and its capture of CO2. The use of a large amount of water in the preparation of this ionic liquid results in the significant formation of the byproduct succinamate anions and difficulties in water removal, which strongly reduces the capacity of CO2 absorption through a bicarbonate mechanism. By contrast, the addition of a small amount of water maintains a high absorption capacity through cooperation. [ABSTRACT FROM AUTHOR]

Abstract: Carbon dots (CDs) have attracted increasing attention in applications such as bio‐imaging, sensors, catalysis, and drug delivery. However, unlike metallic and semiconductor nanoparticles, the transfer of CDs between polar and non‐polar phases is little understood. A class of amine‐terminated CDs is developed and their phase transfer behavior has been investigated. It is found that these CDs can reversibly transfer between aqueous and organic solvents by alternatively bubbling and removing CO2 at atmospheric pressure. The mechanism of such CO2‐switched phase transfer involves reversible acid–base reaction of amine‐terminated CDs with CO2 and the reversible formation of hydrophilic ammonium salts. By using the CDs as catalysts, the phase transfer is applied in the Knoevenagel reaction for efficient homogeneous reaction, heterogeneous separation, and recycling of the catalysts. [ABSTRACT FROM AUTHOR]

Abstract: Carbon dots (CDs) have attracted increasing attention in applications such as bio‐imaging, sensors, catalysis, and drug delivery. However, unlike metallic and semiconductor nanoparticles, the transfer of CDs between polar and non‐polar phases is little understood. A class of amine‐terminated CDs is developed and their phase transfer behavior has been investigated. It is found that these CDs can reversibly transfer between aqueous and organic solvents by alternatively bubbling and removing CO2 at atmospheric pressure. The mechanism of such CO2‐switched phase transfer involves reversible acid–base reaction of amine‐terminated CDs with CO2 and the reversible formation of hydrophilic ammonium salts. By using the CDs as catalysts, the phase transfer is applied in the Knoevenagel reaction for efficient homogeneous reaction, heterogeneous separation, and recycling of the catalysts. [ABSTRACT FROM AUTHOR]

A new strategy involving the computer-assisted design of substituted imidazolate-based ionic liquids (ILs) through tuning the absorption enthalpy as well as the basicity of the ILs to improve SO2 capture, CO2 capture, and SO2/CO2 selectivity was explored. The best substituted imidazolate-based ILs as absorbents for different applications were first predicted. During absorption, high SO2 capacities up to ≈5.3 and 2.4 mol [ABSTRACT FROM AUTHOR]

A novel strategy based on the concept of preorganization and cooperation has been designed for a superior capacity to capture low-concentration CO2 by imide-based ionic liquids. By using this strategy, for the first time, an extremely high gravimetric CO2 capacity of up to 22 wt % (1.65 mol mol−1) and excellent reversibility (16 cycles) have been achieved from 10 vol. % of CO2 in N2 when using an ionic liquid having a preorganized anion. Through a combination of quantum-chemical calculations and spectroscopic investigations, it is suggested that cooperative interactions between CO2 and multiple active sites in the preorganized anion are the driving force for the superior CO2 capacity and excellent reversibility. [ABSTRACT FROM AUTHOR]

Photoelectrochemical (PEC) reduction of carbon dioxide (CO2) is a potential method for production of fuels and chemicals from a C1 feedstock accumulated in the atmosphere. However, the low solubility of CO2 in water, and complicated processes associated with capture and conversion, render CO2 conversion inefficient. A new concept is proposed in which a PEC system is used to capture and convert CO2 into formic acid. The process is assisted by an ionic liquid (1-aminopropyl-3-methylimidazolium bromide) aqueous solution, which functions as an absorbent and electrolyte at ambient temperature and pressure. Within this PEC reduction strategy, the ionic liquid plays a critical role in promoting the conversion of CO2 to formic acid and suppressing the reduction of H2O to H2. At an applied voltage of 1.7 V, the Faradaic efficiency for formic acid production is as high as 94.1 % and the electro-to-chemical efficiency is 86.2 %. [ABSTRACT FROM AUTHOR]

Chemical conversion of CO2 under atmospheric pressure and metal-free conditions remains a great challenge. In this work, a series of alkanolamines, low-cost and biodegradable bases, were used to catalyze the carboxylative cyclization of propargylic amines with CO2. Among these alkanolamines, triethanolamine (TEOA) was found to be a highly efficient organocatalyst for this important transformation at atmospheric pressure, and a series of desired products were synthesized in good to excellent yields. After the reactions, TEOA could be easily recovered and reused without obvious reduction in the efficiency. DFT studies revealed that TEOA may activate CO2 to form a ring-shaped carbonate intermediate that plays an important role in the catalysis of the reaction. This finding provides an effective and environmentally friendly alternative route for the production of 2-oxazolidinones. [ABSTRACT FROM AUTHOR]

The efficient conversion of CO2 into value-added chemicals under metal-free conditions is of significant importance from the viewpoint of sustainable chemistry. In this work, ionic liquids (ILs) with different properties were used to promote the reaction between CO2 and propargylic alcohol for the synthesis of α-alkylidene cyclic carbonates. The protic IL 1,8-diazabicyclo-[5.4.0]-7-undecenium 2-methylimidazolide ([DBUH][MIm]) was prepared by simple neutralization of the superbase with a weak proton donor and could efficiently promote the reactions in high yields. After the reactions, the IL was separated from the reaction mixtures by simply adding water, and then reused after drying without an observable decrease in the catalytic activity and selectivity. NMR spectroscopy and detailed density functional theory analysis were used to propose a reaction mechanism. Both the cation and anion of the IL played a key synergistic role in promoting the reaction. These findings may be useful for the rational design of novel metal-free and recyclable routes for the reaction between CO2 and propargylic alcohols. [ABSTRACT FROM AUTHOR]

NO2 is an effective catalyst for the oxidative thiocyanation of arenes. This unique catalyst is inexpensive and separated easily from the final products because of its low boiling point. The mild reaction conditions allow a series of arenes and thiophenes to be thiocyanated smoothly in moderate to high yields. A preliminary mechanistic investigation suggests that the present reaction may proceed through a radical pathway. [ABSTRACT FROM AUTHOR]

The separation and recycling of catalyst and cocatalyst from the products and solvents are of critical importance. In this work, a class of functionalized ionic liquids (ILs) were designed and synthesized, and by tuning the hydrophilicity and hydrophobicity of cation and anion, respectively, these ILs could reversibly transfer between water and organics triggered upon undergoing a temperature change. From a combination of multiple spectroscopic techniques, it was shown that the driving force behind the transfer was originated from a change in conformation of the PEG chain of the IL upon temperature variation. By utilizing the novel property of this class of ILs, a highly efficient and controllable CuI-catalyzed cycloaddition reaction was achieved wherein the IL was used to entrain, activate, and recycle the catalyst, as well as to control the reaction. [ABSTRACT FROM AUTHOR]

Ionic liquids (ILs) with a reversible hydrophobic-hydrophilic transition were developed, and they exhibited unique phase behavior with H2O: monophase in the presence of CO2, but biphase upon removal of CO2 at room temperature and atmospheric pressure. Thus, coupling of reaction, separation, and recovery steps in sustainable chemical processes could be realized by a reversible liquid-liquid phase transition of such IL-H2O mixtures. Spectroscopic investigations and DFT calculations showed that the mechanism behind hydrophobic-hydrophilic transition involved reversible reaction of CO2 with anion of the ILs and formation of hydrophilic ammonium salts. These unique IL-H2O systems were successfully utilized for facile one-step synthesis of Au porous films by bubbling CO2 under ambient conditions. The Au porous films and the ILs were then separated simultaneously from aqueous solutions by bubbling N2, and recovered ILs could be directly reused in the next process. [ABSTRACT FROM AUTHOR]

A new approach has been developed to improve SO2 sorption by cyano-containing ionic liquids (ILs) through tuning the basicity of ILs and cyano-sulfur interaction. Several kinds of cyano-containing ILs with different basicity were designed, prepared, and used for SO2 capture. The interaction between these cyano-containing ILs and SO2 was investigated by FTIR and NMR methods. Spectroscopic investigations and quantum chemical calculations showed that dramatic effects on SO2 capacity originate from the basicity of the ILs and enhanced cyano-sulfur interaction. Furthermore, the captured SO2 was easy to release by heating or bubbling N2 through the ILs. This efficient and reversible process, achieved by tuning the basicity of ILs, is an excellent alternative to current technologies for SO2 capture. [ABSTRACT FROM AUTHOR]

Nanoplasmonic sensors based on the localized surface plasmon resonance (LSPR) of noble metal nanoparticles have many advantages, such as real-time detection, no need for reagent labelling, and no use of complicated equipment. However, the nanoplasmonic sensors with two dimensional structures usually suffer from a low LSPR signal and thus low sensitivity due to the low density of the nanoparticles. In addition, complicated surface functionalization is always required to suppress the non-specific binding of the analyst to the substrate of the sensor, because the two types of surface, that is, metal and substrate surfaces, are simultaneously exposed to the reaction medium. To overcome these problems, an innovative thermal-induced method has been proposed in the present work, to construct three dimensional (3D) nanostructure of Ag nanocubes on both surfaces of the substrate by using the unique amphiphilic property of 2-diethylaminoethanethiol. The prepared nanoplasmonic sensor is highly sensitive due to the high density of 3D structure of the nanoparticles and the low non-specific binding since only one type of surface is exposed. To enhance the stability of the sensor, a thin SiO2 overlayer was formed on the surface without using an additional coupling agent. Furthermore, the NiII-nitriloacetic acid (NiII-NTA) complex was covalently bound on the surface, so that the regeneration and reuse of the sensor becomes easy. Therefore, the easy fabrication, high stability, and good reusability of this 3D LSPR sensor makes our method competitive for the development of nanoplasmonic sensors. [ABSTRACT FROM AUTHOR]

ABSTRACT In the present study, the acute and developmental toxicities of imidazolium ionic liquids (ILs) with different alkyl chain lengths, as well as the antioxidant response and lipid peroxidation levels were evaluated in the snail, Physa acuta. Longer alkyl chains corresponded to increased IL toxicity in snails. Long-term IL exposure at lower concentrations inhibited snail growth and reproduction. We also found that IL inhibited the activities of superoxide dismutase (SOD) and glutathione S-transferase (GST), promoted the activity of catalase (CAT), and increased the glutathione content. However, SOD, GST, and CAT activities returned to control levels after 96 h of recovery. In addition, malondialdehyde levels were increased in treatment groups compared with the control and did not return to control levels even after a recovery period, indicating that ILs induced lipid peroxidation in snail viscera. These results suggest that oxidative stress and lipid peroxidation may be involved in the mechanism of toxicity for ILs. [ABSTRACT FROM AUTHOR]

Breaking point: An effective reductive cleavage of inert aryl CO bonds with an inexpensive iron catalyst has been developed. During this process, the reduction of the arene rings was not observed. This catalytic system also enabled the selective cleavage of the β‐O‐4 linkage of lignin model compounds under an atmosphere of hydrogen, thus offering an opportunity for the depolymerization of lignin. [ABSTRACT FROM AUTHOR]

Nitrogen dioxide is demonstrated to be an effective catalyst precursor for the iodination of alkoxy-substituted benzenes and naphthalenes. Different from the transition metal catalysts, nitrogen dioxide can be easily separated from the final products, and is free of heavy metal waste. Although the present catalyst precursor is toxic, it does not stain the final products due to its low-boiling character. No other reagents apart from 0.5 equiv. of iodine (I2), 6.5 mol% nitrogen dioxide and acetonitrile solvent were used in the iodination, and basically all the iodine atoms in the iodine source were transferred to the iodination products, showing that the presented protocol is highly atom-economic and practical. [ABSTRACT FROM AUTHOR]

ABSTRACT This study aims to evaluate the cytotoxicity and responses of the cellular antioxidant system of 1-octyl-3-methylimidazolium chloride ([C8mim][Cl]) on human hepatocarcinoma QGY-7701 cells. The results show that [C8mim][Cl] can inhibit QGY-7701 cell growth and decrease their viabilities in a dose-dependent manner. The results also reveal that [C8mim][Cl] exposure can induce apoptosis in the [C8mim][Cl]-treated QGY-7701 cells. In addition, the results of biochemical assays show that [C8mim][Cl] exposure causes overproduction of reactive oxygen species (ROS), inhibits superoxide dismutase (SOD) and catalase (CAT) activities, decreases reduced glutathione (GSH) content, and increases the cellular malondialdehyde (MDA) level. These results suggest that ROS-mediated oxidative stress may be responsible for the apoptosis induced by [C8mim][Cl] in QGY-7701 cells. © 2013 Wiley Periodicals, Inc. J BiochemMol Toxicol 27:330-336, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/jbt.21495 [ABSTRACT FROM AUTHOR]

Recovery is a very important factor for the industrial application of ionic liquids (ILs). In this work, a novel method is presented for the recovery of ILs by using carbon dioxide (CO2)-induced formation of aqueous two-phase systems (ATPSs). It was found that, in the presence of amines, introduction of CO2 into aqueous IL solutions leads to the formation of ATPSs at 25 °C and atmospheric pressure, in which the upper phase is ammonium-salt-rich and the lower phase is IL-rich. Thus, the ILs in aqueous solutions can be significantly enriched, and the amines can be regenerated by heating and bubbling Ar or N2 in the salt-rich phase. To better understand the recovery of ILs, the phase diagrams of the ATPSs were measured at 25 °C, and the effects of the molecular structure of the ILs and the amines and temperature of the systems on the recovery efficiency of the ILs were investigated. It was shown that the single-step recovery efficiency of the ILs could be as high as 99 % in the presence of primary or secondary amines. Therefore, this new method could potentially be sustainable, efficient, and attractive to industry. [ABSTRACT FROM AUTHOR]

A simple method was developed for selective para-cyanation of alkoxy- and benzyloxy-substituted benzenes with 0.5 equivalents of potassium ferricyanide, 0.8 equivalants of copper(II) nitrate and 0.5 equivalents of iodine in acetonitrile. Among various phenyl carbon-hydrogen bonds, those at the para-position with regard to the alkoxy or benzyloxy groups were selectively cyanated in 20% to 87% yields (23 examples). The present method uses commercially available reagents, and can be performed on a ten gram-scale. Interestingly, methoxybenzene was cyanated in 32% yield in the absence of potassium ferricyanide, which suggests that the nitrile group of a part of the product is possibly from the solvent acetonitrile. [ABSTRACT FROM AUTHOR]

Small AgPd ( n = 5) clusters and their hydrides AgPdH ( n = 5) have been studied by density functional theory calculations. For bare clusters, the structures in which the Pd atom has a maximum number of neighboring Ag atoms tend to be energetically favorable. Hydrogen prefers binding to AgPd bridge site of AgPd clusters except for AgPd. The binding energy has a strong odd-even oscillation. The electron transfers are from Ag atoms to Pd in bare clusters and are from metal clusters to H in cluster hydrides. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011 [ABSTRACT FROM AUTHOR]

A three-dimensional miscible transport model for seawater intrusion in a phreatic aquifer with a transition zone is presented. This model considers many important factors, such as the effect of variable density on fluid flow, the effect of precipitation infiltration and phreatic surface fluctuation on the process of seawater intrusion, the existence of great discharge pumping wells, etc. The difficulty in solving this problem can be tackled by the presented numerical method and iteration technique. This model is used to describe seawater intrusion in Huangheying, Longkou, People's Republic of China. The simulated values agree very well with the field data (e.g., the total mean values of the absolute error of Cl− concentration are 46.13 mg/L and 55.67 mg/L, respectively, and those of the water head are 0.24 m and 0.08 m, respectively). [ABSTRACT FROM AUTHOR]