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The factors affecting the bound acrylonitrile content of NBR product during the polyme-rization process were investigated, including monomer reactivity ratio, monomer conversion, monomer concentration, and polymerization temperature and pressure, the structural composition of the product was analyzed, and the polymerization reaction kinetics and repeatability experiment were carried out. The results showed that under the polymerization temperature of 5.0 ℃ and polymerization pressure of 0.15-0.20 MPa, NBR products with uniform distribution of acrylonitrile structure units and mass fraction of bound acrylonitrile of 17%-19% could be obtained by using multi-stage addition of acrylonitrile and controlling the monomer conversion of 70%-75%. The polymerization formula and process had good repeatability.

A type of Al-MCM-41 supported dual imidazolium ionic liquids were constructed and efficiently used as catalysts for the synthesis of 2-oxazolidinones from epoxides, amines, and CO2. The influence of the different catalysts and reaction parameters on the catalytic behaviours was investigated. Al-MCM-41@ILTiCl5 was identified as the most excellent catalyst because it could efficiently promote the three-component cycloaddition of CO2, epoxide, and amines to form the corresponding 2-oxazolidinones in high to excellent yields (84∼96%) with excellent selectivities (98∼99.7%). In addition, the recovery and reuse performances of Al-MCM-41@ILTiCl5 were examined. The catalyst could be recovered by simple filtration and reused six times without a change in the catalytic activity. Green reaction conditions, operational simplicity, feasibility, and sustainability of the functionalized catalyst are the main highlights of the present protocol. [ABSTRACT FROM AUTHOR]

The efficient conversion of CO2 into value-added chemicals is of great importance. Herein, a type of transition metal-doped MCM-41 supported ionic liquids were synthesized, and efficiently used as catalysts for the effective carboxylative cyclization of propargylic alcohols and CO2 into α-alkylidene cyclic carbonates. The supported catalyst Cu-MCM-41@ILTiCl5 with a synergistic effect between the active copper sites and the anion could efficiently promote the carboxylative cyclization of propargylic alcohols and CO2 in high to excellent yields. After the reaction, the catalyst could be easily separated from the reaction mixture by simple centrifugation, and then reused for six times without noticeable decrease in the catalytic activity.These findings may be useful for the rational design of novel highly active and efficient catalysts for the transformation of CO2 into value-added α-alkylidene cyclic carbonates. An efficient protocol has been developed for producingα-alkylidene cyclic carbonates in excellent yields under cocatalyst- and solvent-free conditions by treating propargylic alcohols with carbon dioxide, promoted by Cu-MCM-41 supported ionic liquid catalyst. [ABSTRACT FROM AUTHOR]

In this work, a class of transition metal-modified MCM-41 mesoporous silica supported ionic liquids nanocatalysts were constructed and efficiently used as catalysts for the effective carboxylation of terminal alkynes through CO2 utilization. The main factors affecting the catalytic performance of carboxylation and its possible reaction mechanism were sufficiently discussed. The results showed that when the dosage was 0.2 g, the temperature was 40°C and the CO2 pressure was 0.3 MPa, the supported catalyst MCM-41@IL-Sm showed the optimal catalytic efficiency. The novel catalyst proved to be highly efficient for the sustainable synthesis of alkynyl carboxylic acids attributing good to excellent yields of 82%–95% within 7–12 h. Moreover, MCM-41@IL-Sm could be recycled and reused six times without noticeable decrease in catalytic activity from two-phase system under external heterogeneous field. The application of supported ionic liquids in the field of carbon dioxide carboxylation has injected a new power source for the efficient and effective production of value-added chemicals from waste CO2. [ABSTRACT FROM AUTHOR]

In this study, we report a successful strategy for the generation of a type of multifunctional heterogeneous supported ionic liquids catalysts. The synthesized supported ionic liquids (Fe‐MCM‐41/IL) were used in the catalytic cyclocondensation of 2‐aminobenzamide and various ketones and aldehydes towards the efficient synthesis of the dihydroquinazolinones under green conditions. The influence of the different catalysts and reaction parameters on the catalytic behaviors were sufficiently investigated. The supported catalyst (2)Fe‐MCM‐41/IL(0.6) showed the optimal catalytic efficiency. A hot filtration experiment revealed that the reaction proceeded in a heterogeneous pathway. The catalytic activity of (2)Fe‐MCM‐41/IL(0.6) could be maintained efficiently after recycling up to five consecutive runs under the optimized reaction conditions. Merits of this meticulously designed protocol are the use of novel supported catalyst, easy work‐up process, feasibility and sustainability, indicating its potential industrial application prospect. [ABSTRACT FROM AUTHOR]

A type of MCM-41 supported dual imidazolium ionic liquids have been synthesized and efficiently used as catalysts in the sustainable chemical conversion of CO2 and epoxides into cyclic carbonates. It was shown that the highest efficiency was achieved in the cycloaddition of a variety of epoxides and CO2 in the presence of the MCM-41@DILSCN solid catalyst under mild conditions. More interestingly, the catalyst was stable, very active, robust, and displayed good recyclability without significant loss of catalytic activity after six consecutive cycles during the process. Overall, the present protocol of synthesizing cyclic carbonates under solvent free conditions using MCM-41@DILSCN is promising for industrial applications. [ABSTRACT FROM AUTHOR]

Efficient and sustainable chemical fixation of CO2 into value-added chemicals is one of the most promising objectives in environmental chemistry. In this work, transition metal acetylacetonate immobilized onto triazolium ionic liquid-modified periodic mesoporous organosilica PMO-IL-M(x) was successfully prepared and investigated as an effective and heterogeneous catalyst in the direct carboxylation of terminal alkynes and CO2 to the desired alkynyl carboxylic acids. It was found that the catalyst PMO-IL-Sn(0.3) exhibited extraordinary catalytic performance in terms of excellent activity, stability, productivity, and excellent yields under mild reaction conditions. Moreover, the catalyst PMO-IL-Sn(0.3) could be easily recovered and reused at least six times without considerable loss in catalytic activity. This work provides a sustainable and efficient synergistic strategy for the chemical fixation of carbon dioxide into valuable alkynyl carboxylic acids. [ABSTRACT FROM AUTHOR]

An efficient, experimentally simple, and convenient procedure for the C-O coupling of organic halides with phenols and alcohols in a [PEG.sub.1000]-DAIL[Cd[Cl.sub.3]]-toluene temperature-dependent biphasic system has been developed. The product can be easily isolated by a simple decantation, and the catalytic system can be recycled and reused without loss of catalytic activity. Key words: C-O coupling, organic halide, ionic liquid, thermoregulated ionic liquid biphasic system. On a mis au point une meethode commode, efficace et experimentalement simple de faire un couplage C-O d'halogenures organiques avec des phenols et des alcools dans un systeme biophysique [PEG.sub.1000]-DAIL[Cd[Cl.sub.3]]-toluene qui varie avec la temperature. Les produits peuvent etre facilement isoles par une simple decantation et le systeme catalytique peut etre recycle; et reutilise dans perte d'activite catalytique. Mots-cles : couplage C-O, halogenure organique, liquide ionique, systeme biphasique de liquide ionique soumis a une thermoregulation. [Traduit par la Redaction], Introduction The carbon-oxygen bond-forming reaction is one of the most fundamental transformations because of the large number of applications of the resulting compounds (ethers) in organic, pharmaceutical, and polymer chemistry. [...]

The various effects of chaotropic perturbation (CP) on the specification of human plasma high-density lipoprotein (HDL) are being studied. The size and the relative amount of HDL lipid are found to be the main determinants of the HDL stability and the apolipoprotein (apo) A-I partitioning.

A type of mesoporous SBA-15 supported imidazolium functionalized ionic liquids were prepared, characterized and tested as effective and practical catalysts for the synthesis of 2-oxazolidinones by the cycloaddition of CO2 and aziridines. The effects of reaction parameters such as type of catalysts, catalyst amount, CO2 pressure, reaction temperature and catalyst stability have also been investigated in detail, the catalyst SBA-15@DMIL-HOCH2COO exhibited high activity with good yields and excellent regioselectivities. In addition, the catalyst can be easily and effectively recycled for five times with no significant loss in its catalytic activity and selectivity. This work introduces a new, convenient, highly efficient and environmentally friendly pathway to explore the supported ionic liquids for the chemical fixation of carbon dioxide. [ABSTRACT FROM AUTHOR]

Periodic mesoporous organosilica (PMO) supported ionic liquids with high catalytic ability were prepared and tested in synthesis of 2‐oxazolidinones from the three‐component cycloaddition reactions of CO2, aryl amines and epoxide. The functionalized PMO material PMO@TZ‐ILSmCl4 revealed the most excellent catalytic performance than PMO@TZ‐ILLaCl4 during the catalytic synthesis of 2‐oxazolidinones. Different parameters such as catalyst loading, temperature, CO2 pressure and reaction time were also investigated. Good to excellent yields for 2‐oxazolidinones and stable reusability were reached in the CO2 cycloaddition under solvent‐ /ligand‐free conditions. This work provides a useful route to design novel and highly efficient catalytic systems for the transformation of CO2 into other valuable 2‐oxazolidinones. [ABSTRACT FROM AUTHOR]

Background: Thyroid carcinoma (TC) is the most common malignancy of the endocrine system. Circular RNA (circRNA) is vital in the regulation of tumor progression. Circ_0000144 serves as a novel oncogenic circRNA, and miR‐217 is reported to inhibit the malignant phenotypes of cancer cells by targeting AKT3 in TC. The present study aimed to explore the regulatory mechanism of circ_0000144 and miR‐217 in the progression of TC. Methods: Circ_0000144 expression in 32 pairs of TC tissues and different TC cell lines (including BCPAP, K1, H7H83, and TPC‐1) was detected by employing a quantitative real‐time polymerase chain reaction (qRT‐PCR). Circ_0000144 small interfering RNA was used to establish loss‐of‐function models. Cell counting kit‐8 (CCK‐8), BrdU (5‐bromo‐2'‐deoxyuridine) and transwell assays were utilized to verify the effects of circ_0000144 on TC cell proliferation, migration and invasion, respectively. Bioinformatics, western blotting, a luciferase reporter experiment and qRT‐PCR were employed to confirm the relationships among circ_0000144, miR‐217 and AKT3. Results: Circ_0000144 expression was remarkably elevated in TC tissues (p < 0.001) and TC cell lines. The elevation of circ_0000144 expression was markedly linked to tumor size (p = 0.015), TNM stage (p = 0.025) and lymph node metastasis (p = 0.017) of the patients. Functional studies showed that knocking down circ_0000144 repressed the malignancy of TC cells. Furthermore, miR‐217 was identified as a downstream target of circ_0000144; inhibition of miR‐217 could reverse the effects induced by circ_0000144 knockdown. Moreover, circ_0000144 could regulate AKT3 expression by suppressing miR‐217 expression. Conclusions: Circ_0000144 exerts a cancer‐promoting effect on TC cells via the miR‐217/AKT3 pathway. [ABSTRACT FROM AUTHOR]

An immobilized benzotriazolium ionic liquid system has been developed for the efficient catalytic transformation of CO2 to cyclic carbonates without using any co‐catalyst or solvent. Two novel multifunctional periodic mesoporous organosilica supported benzotriazolium ionic liquids PMO‐ILTiCl5 and PMO‐ILSnCl5 were prepared, characterized and demonstrated excellent catalytic activity in the cycloaddition of CO2 with epoxides. The superior catalytic performance was observed for PMO‐ILTiCl5 in the synthesis of cyclic carbonates with high yields and selectivities. Furthermore, the catalyst PMO‐ILTiCl5 could be separated readily and reuse for at least five successful times without obvious losses in its catalytic activity, owing to the presence of intramolecular synergistic effect between active hydroxyl sites and TiCl5 nucleophile and thus provide sufficiently stable catalytic sites. Therefore, this work provided a novel strategy for highly efficient and environmentally benign catalytic conversion of CO2 to cyclic carbonates. [ABSTRACT FROM AUTHOR]

Tbe human hepatoma cells and lipoprotein receptor-specific Chinese hamster ovary (CHO) cells are utilized to test the hypothesis that hepatic uptake of cholesteryl ester-rich microemulsion (CERM) that contains the cholesterol esters (CE) via multiple apo E-dependent receptors would be faster than that of high-density lipoproteins (HDL)-CE. The obtained data demonstrated that serum opacity factor (SOF) treatment of HDL increased the rate of CE uptake via multiple hepatic apo E receptors.

A new methodology for the highly efficient and atom‐economic oxidation of alcohols and benzylic compounds to the corresponding aldehydes and ketones with environmental‐friendly hydrogen peroxide using a magnetic MOF nanocatalyst has been developed. We demonstrated that the resulting magnetic nanocomposite CoFe2O4@SiO2@MIL‐53(Fe) can show excellent catalytic performances in the highly selective oxidation at room temperature, based on a synergetic effect between iron sites and CoFe2O4@SiO2. The nanocatalyst offers simple operation for recovery and the recycling test showed that it could be reused for successive runs without significant degradation in catalytic activity. [ABSTRACT FROM AUTHOR]

A range of multifunctional magnetic metal–organic framework nanomaterials consisting of various mass ratios of the metal–organic framework MIL-53(Fe) and magnetic SiO2 @NiFe2 O4 nanoparticles were designed, prepared, characterized, and evaluated as heterogeneous catalysts for the Knoevenagel condensation. The as-fabricated nanomaterials, especially the nanocatalyst MIL-53(Fe)@SiO2 @NiFe2 O4 (1.0), showed good catalytic performance in the Knoevenagel condensation at room temperature as a result of synergistic interaction between the Lewis acid iron sites of MIL-53(Fe) and the active sites of the magnetic SiO2 @NiFe2 O4 nanoparticles. In addition, the heterogeneous catalyst was readily recovered and a recycling test showed that it could be reused for five times without significant loss of its catalytic activity, making it economical and environmentally friendly. [ABSTRACT FROM AUTHOR]

Mesoporous material supported functionalized ionic liquids have been designed and synthesized, characterized and evaluated as novel heterogeneous catalysts for the Hantzsch reaction. The as‐fabricated catalysts show good performance in the Hantzsch synthesis of 1,4‐dihydropyridines under ambient conditions, especially the titanium incorporated mesoporous material supported ionic liquid Ti‐SBA‐15@IL‐BF4, based on a synergetic effect of titanium site of mesoporous material carrier and the acidic sites of ionic liquid. In addition, the heterogeneous catalyst offers simple operation for recovery and the recycling test showed that it could be reused for five times without significant loss of catalytic activity. Mesoporous material supported functionalized ionic liquids have been designed and synthesized, and evaluated as heterogeneous catalysts for the Hantzsch reaction. Research shows that Ti‐SBA‐15@IL‐BF4 show the best catalytic performance under ambient conditions. The catalyst offers simple operation for recovery and the recycling test showed that it could be reused for five runs without significant loss of catalytic activity, thus making this method economical and environment‐friendly. [ABSTRACT FROM AUTHOR]