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Ionic liquids (ILs) as green solvents were first used to capture 1,2-dimethoxyethane (DMET) from exhaust gas. The vapor liquid equilibrium (VLE) data of [EMIM][TF2N] + DMET and triethylene glycol (TEG) + DMET were measured. The results showed that the popular UNIFAC-Lei model is in good agreement with experimental data. The gas absorption experiment with [EMIM][TF2N] as absorbent was conducted. It demonstrates that the IL has good separation performance for capturing DMET, the absorption ratio being 87.32%. Then, the absorption capacities of 45 ILs for DMET were calculated by COSMO-RS model, while DMET removal mechanism was explored by σ-profiles analysis and molecular dynamics (MD) simulation. Finally, industrial scale process simulation using [EMIM][TF2N] and TEG as absorbents to capture DMET was made. Compared to the benchmark TEG process, the total operating cost and the total annual cost (TAC) in the IL process decrease by 24.06% and 17.15%, respectively. This further proves that ILs have great application potential for the condensable volatile organic compounds (VOCs) capture, especially in energy saving and improving economic benefits.

Acetonitrile is an important and widely used organic solvent, but its production is limited by its production process. In this study, a new process for the amination of ethanol to acetonitrile was developed. On the basis of the reaction kinetics, the operating conditions of reaction temperature and raw material ratio were optimized. Comprehensive economic, thermodynamic, and environmental analyses were used to improve the production performance and energy utilization. Thermodynamic analysis of the acetonitrile production process shows that the separation and purification unit and product refining unit make the most critical contributions to exergy loss. The introduction of heat integration technology can effectively recover process energy and reduce the energy consumption of the whole process. On the basis of the highest product yield, the total annual cost was 6.34 × 106$/year. The exergy efficiency of the amination process to convert ethanol to acetonitrile was 56%, which could be thermodynamically improved. Environmental analysis showed that the reaction synthesis unit had a greater environmental effect than the other two studied units. A new method combining process simulation, economics, thermodynamics, and environmental performance analysis is proposed to improve the energy efficiency and quality of the acetonitrile production process.

Predictive molecular thermodynamic models are significant for predicting basic thermodynamic properties, such as fluid phase equilibrium in chemical separation processes and the subsequent simulation and amplification of industrial processes. Considering that some group binary interaction parameters between ionic liquid (IL) groups and traditional substance groups in the original UNIFAC model are still missing, 18 pairs of parameters are obtained by collecting experimental data from the new literature. On the other hand, the remaining 1570 pairs of interaction parameters are expanded by the COSMO-UNIFAC model, with other parameters missing from the literature data. The prediction of gas–liquid equilibrium, liquid–liquid equilibrium, gas–liquid equilibrium, and infinite dilution activity coefficient is used to evaluate the prediction performance of the newly extended UNIFAC model for phase equilibria of systems containing ionic liquids.

Using new green solvents to effectively capture volatile organic compounds (VOCs) is considered as an attractive green sustainable chemical development route. In this work, benzene, toluene, ethylbenzene and p-xylene (BTEX) were selected as typical aromatic VOCs. The gas absorption performance of proton [MIM][NTF2] and aprotic [EMIM][NTF2] ionic liquids (ILs) for BTEX were studied by computational thermodynamics combined with gas absorption experiments. Absorption experiments of BTEX and regeneration experiments of ILs were carried out at different temperatures, and ILs had good stability. The interaction type and intensity were determined by Interaction Region Indicator (IRI) analysis of IL-BTEX blend systems. The C-H···π and π-π interaction between imidazole ring and BTEX were the direct reason why ILs can efficiently absorb BTEX. Molecular dynamics simulations were performed to explore the diffusion behavior of gas in ILs. The increase of methyl group increases the interaction strength of the system, and the fractional free volume of IL-BTEX blend systems decreases gradually, which limits the diffusion of BTEX. Non-bond interaction analysis shows that van der Waals interaction was the main driving force of BTEX absorption in ILs.

Biogas, as a cheap and easily available clean biomass energy, has attracted extensive attention. In this work, the simultaneous decarburization, desulfurization and dehydration of biogas with ionic liquids (ILs) was proposed. Based on the COSMO-RS model, the separation performance of 400 ILs composed of 20 cations and 20 anions was screened by using Henry's law constant (HLC) and selectivity coefficient as separation performance indexes. Among them, 1,3-dimethylimidazolium methylsulfate [C1MIM][MeSO4] was considered to be the most promising candidate absorbent. Furthermore, the HLC and selectivity of CH4, CO2and H2S in [C1MIM][MeSO4] were predicted by COSMO-RS at different temperatures and pressures. The results show that the selected [C1MIM][MeSO4] has excellent selective absorption performance for CO2and H2S. The regeneration experiment of [C1MIM][MeSO4] showed that the absorption effect of CH4, CO2and H2S was almost unchanged (i.e., HLC was almost unchanged) after 6 absorption-desorption cycles. Molecular surface electrostatic potential (ESP) analysis was performed to obtain the binding sites of intermolecular interactions to reveal the separation mechanism of simultaneous decarbonization, desulfurization and dehydration of ILs. Interaction region indicator (IRI) analysis showed that IL [C1MIM][MeSO4] mainly interacted with the components to be separated in the form of hydrogen bonds. The spatial distribution function (SDF) reveals the spatial distribution of different gases around [C1MIM][MeSO4] from the perspective of cluster macromolecules. This provides theoretical insights into molecular thermodynamics and dynamics for the development of new ILs for biogas purification.

The structure–property relationship between ionic liquids (ILs) and two chlorinated volatile organic compounds (CVOCs), dichloromethane (DCM) and 1,2-dichloroethane (DCE), was systematically investigated. The suitable IL was screened using the COSMO-RS model, and 1-ethyl-3-methylimidazolium acetate [EMIM][Ac] was considered the optimal absorbent to capture the two CVOCs. The vapor–liquid equilibrium experiment demonstrates that the addition of the IL significantly reduces the vapor pressures of the IL + DCM (or DCE) systems. The structure of ILs on the absorption performance was investigated by absorption capacity experiments. Then, the absorption mechanism was investigated through QC calculations and wavefunction analysis. The consistency between the experiments and the molecular mechanism reveals that the formation of the hydrogen bond between the IL and CVOC enhances the absorption process.

ABSTRACTProstaglandins, pleiotropic immune modulators that induce protein kinase A (PKA), inhibit gamma interferon induction of class II major histocompatibility complex (MHC) genes. We show that phosphorylation of CIITA by PKA accounts for this inhibition. Treatment with prostaglandin E or 8-bromo-cyclic AMP or transfection with PKA inhibits the activity of CIITA in both mouse and human monocytic cell lines. This inhibition is independent of other transcription factors for the class II MHC promoter. These same treatments also greatly reduced the induction of class II MHC mRNA by CIITA. PKA phosphorylation sites were identified using site-directed mutagenesis and phosphoamino acid analysis. Phosphorylation at CIITA serines 834 and 1050 accounts for the inhibitory effects of PKA on CIITA-driven class II MHC transcription. This is the first demonstration that the posttranslational modification of CIITA mediates inhibition of class II MHC transcription.

Prostaglandins, pleiotropic immune modulators that induce protein kinase A (PKA), inhibit gamma interferon induction of class II major histocompatibility complex (MHC) genes. We show that phosphorylation of CIITA by PKA accounts for this inhibition. Treatment with prostaglandin E or 8-bromo-cyclic AMP or transfection with PKA inhibits the activity of CIITA in both mouse and human monocytic cell lines. This inhibition is independent of other transcription factors for the class II MHC promoter. These same treatments also greatly reduced the induction of class II MHC mRNA by CIITA. PKA phosphorylation sites were identified using site-directed mutagenesis and phosphoamino acid analysis. Phosphorylation at CIITA serines 834 and 1050 accounts for the inhibitory effects of PKA on CIITA-driven class II MHC transcription. This is the first demonstration that the posttranslational modification of CIITA mediates inhibition of class II MHC transcription.

ABSTRACTScaffold molecules interact with multiple effectors to elicit specific signal transduction pathways. CIITA, a non-DNA-binding regulator of class II major histocompatibility complex (MHC) gene transcription, may serve as a transcriptional scaffold. Regulation of the class II MHC promoter by CIITA requires strict spatial-helical arrangements of the X and Y promoter elements. The X element binds RFX (RFX5/RFXANK-RFXB/RFXAP) and CREB, while Y binds NF-Y/CBF (NF-YA, NF-YB, and NF-YC). CIITA interacts with all three. In vivo analysis using both N-terminal and C-terminal deletion constructs identified critical domains of CIITA that are required for interaction with NF-YB, NF-YC, RFX5, RFXANK/RFXB, and CREB. We propose that binding of NF-Y/CBF, RFX, and CREB by CIITA results in a macromolecular complex which allows transcription factors to interact with the class II MHC promoter in a spatially and helically constrained fashion.

Scaffold molecules interact with multiple effectors to elicit specific signal transduction pathways. CIITA, a non-DNA-binding regulator of class II major histocompatibility complex (MHC) gene transcription, may serve as a transcriptional scaffold. Regulation of the class II MHC promoter by CIITA requires strict spatial-helical arrangements of the X and Y promoter elements. The X element binds RFX (RFX5/RFXANK-RFXB/RFXAP) and CREB, while Y binds NF-Y/CBF (NF-YA, NF-YB, and NF-YC). CIITA interacts with all three. In vivo analysis using both N-terminal and C-terminal deletion constructs identified critical domains of CIITA that are required for interaction with NF-YB, NF-YC, RFX5, RFXANK/RFXB, and CREB. We propose that binding of NF-Y/CBF, RFX, and CREB by CIITA results in a macromolecular complex which allows transcription factors to interact with the class II MHC promoter in a spatially and helically constrained fashion.

Ionic liquids (ILs) were developed to separate polycyclic aromatic hydrocarbons (PAHs) from real diesel from the molecular scale to the process system. Based on the liquid–liquid equilibrium data, the popular UNIFAC-Lei model was adopted and improved. A simulation comparison of real FCC diesel (including 712 components) with model oil (only n-hexadecane + 1-methylnaphthalene) indicates that the former is closer to experimental data, with the average relative deviation (ARD) being only 6.71%, showing the significance of considering all molecules in molecular refining.

To further reduce the energy consumption, investment and operation cost of the distillation process, DWC-B and FTCDC are used to strengthen the separation process of ibuprofen sodium mother liquor. Based on the process simulation results, thermodynamic efficiency, economic and environmental impact assessment were carried out and compared with the benchmarked CTCD process. DWC-B and FTCDC have obvious advantages in economy, energy saving and environmental impact. Compared with the benchmarked CTCD process, the FTCDC process is more attractive economically, and its total annual cost is reduced by about 7.83%. The thermodynamic efficiency of DWC-B is 17.62%, and the CO2emission is reduced by 11.39%. Compared with the benchmarked CTCD process, DWC-B and FTCDC have the advantages of high thermodynamic efficiency, low economic cost and low CO2emission with a great industrial application prospect.

Paclitaxel (Taxol) is a novel anti-cancer drug that has shown efficacy toward several malignant tumors, particularly ovarian tumors. We reported previously that paclitaxel can induce interleukin (IL)-8 promoter activation in subgroups of ovarian cancer through the activation of both AP-1 and nuclear factor κB. Further analysis of paclitaxel analogs indicates that the degree of IL-8 induction by analysis correlates with the extent of cell death; however, IL-8 itself is not the cause of cell death.This suggests that pathways that lead to IL-8 and cell death may overlap, although IL-8 per sedoes not kill tumor cells.To decipher the upstream signals for paclitaxel-induced transcriptional activation and cell death, we studied the involvement of protein kinases that lead to the activation of AP-1, specifically the c-Jun NH2-terminal kinase (JNK1), p38, and the extracellular signal-regulated kinase 1 (ERK1). The role of IκB in paclitaxel-induced cell death was also analyzed. Paclitaxel activated JNK, and to a lesser degree p38, but not ERK1. Paclitaxel-induced IL-8 promoter activation was inhibited by dominant-inhibitory mutants of JNK, p38,and the super-repressor form of IκBα, but not by dominant-inhibitory forms of ERK1. Dominant-inhibitory mutants of JNK1 also greatly reduced paclitaxel-induced cell death, and the kinetics of JNK induction was closely followed by DNA fragmentation. These results indicate (i) that paclitaxel activates the JNK signaling pathway and (ii) that JNK activation is a common point of paclitaxel-induced gene induction and cell death.

Owing to the negative environmental impact and safety problems of fossil fuel resources, chemical processes based on renewable energy have been extensively studied for further development. In this study, the thermodynamic, economic, and environmental performances of biomass-to-hydrogen (BTH) conversion were assessed using corn straw as a raw material. Further, the process used to achieve BTH conversion with/without carbon capture and storage (CCS) was evaluated and analyzed in this study. According to the simulation results, the economic and environmental properties of BTH processes using different CO2capture rates were evaluated via thermodynamics and life cycle assessment. Compared with the biomass hydrogen production process without CCS, the EC of the BTH process with CCS decreased by 17%. However, the total investment and production cost of biomass hydrogen production with CCS increased by 1.3% and 14.6-19.4%, respectively. The energy efficiency of BTH conversion with CCS was 17% lower than that of BTH conversion without CCS. Further, the payback period of the BTH process performed with CCS was approximately 5–6 years. According to the energy consumption and the economic and environmental performances, BTH conversion with a CO2capture rate of 80% is a appropriate CCS system for CO2capture. The life cycle assessment of BTH conversion demonstrates that the BTH system with CCS can result in negative greenhouse gas emissions. The development of the BTH process using CCS is thus of great significance for achieving carbon neutralization.