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Quantitative evaluation of vertical ionization energy (VIE) of solute in solution is a challenge for modern computational chemistry. We derived the expression of VIE in solution and found that the nonequilibrium solvation free energy plays a key role. Using the novel nonequilibrium solvation theory developed by our group, we established the expression of nonequilibrium solvation free energy and implemented its numerical algorithm in PCM part of Q-Chem package. To prove its correctness, the solvation shifts of VIE for alkali metal cations were calculated. The obtained results are in good agreement with available experimental findings. Finally, we investigated the vertical ionization processes of four DNA bases: guanine, adenine, cytosine and thymine. The computed results can reasonably explain the experimental findings and indicate that nonequilibrium polarization is crucial to VIE in solution. [ABSTRACT FROM AUTHOR]

Photodynamic therapy (PDT) has emerged as an important minimally invasive tumor treatment technology. The search for an effective photosensitizer to realize selective cancer treatment has become one of the major foci in recent developments of PDT technology. Controllable singlet-oxygen release based on specific cancer-associated events, as another major layer of selectivity mode, has attracted great attention in recent years. Here, for the first time, we demonstrated that a novel mixed-metal metal-organic framework nanoparticle (MOF NP) photosensitizer can be activated by a hydrogen sulfide (H2S) signaling molecule in a specific tumor microenvironment for PDT against cancer with controllable singlet-oxygen release in living cells. The effective removal of tumors in vivo further confirmed the satisfactory treatment effect of the MOF NP photosensitizer. [ABSTRACT FROM AUTHOR]

A series of ZrO-TiO-AlO composite oxides with different AlO ratios were prepared by coprecipitation method and used as the supports of Pt/NiO-MoO/ZrO-TiO-AlO catalysts. Catalytic activities for n-decane cracking over these catalysts were evaluated under high temperature and high pressure conditions. Physicochemical characteristics of as-prepared catalysts were detected by using automatic adsorption instrument, X-ray diffractometer, temperature programmed reduction, and temperature programmed desorption techniques to characterize the catalysts and supports. The results indicated that the catalyst which contained 60 wt % AlO had the largest surface area and pore volume (152.7 m/g and 0.39 mL/g, respectively), and also it possessed strongest medium and strong acidity as well as medium acidic density. Moreover, the catalyst with 60 wt % AlO exhibited better cracking performances compared with the others. The gas yields over Cat3 were 1.5 and 1.2 folds higher than that obtained from thermal cracking at 650 and 700°C, respectively. In addition, the heat sinks were improved 0.27 MJ/kg and 0.25 MJ/kg at 650 and 750°C, respectively. [ABSTRACT FROM AUTHOR]

Plasmacytoid dendritic cells (pDCs) exert dual roles in immune responses through inducing inflammation and maintaining immune tolerance. A switch of pDC phenotype from pro-inflammation to tolerance has therapeutic promise in the treatment of autoimmune diseases. Vinpocetine, a vasoactive vinca alkaloid extracted from the periwinkle plant, has recently emerged as an immunomodulatory agent. In this study, we evaluated the effect of vinpocetine on phenotype of pDCs isolated from C57BL/6 mice and explored its possible mechanism. Our data showed that vinpocetine significantly downregulated the expression of CD40, CD80, and CD86 on pDCs and increased the expression of translocator protein (TSPO), the specific receptor of vinpocetine, in pDCs. Vinpocetine significantly inhibited the Toll-like receptor 9 signaling pathway and reduced the secretion of related cytokines in pDCs through TSPO. Furthermore, viability of pDCs was significantly promoted by vinpocetine. These findings imply that vinpocetine serves as an immunomodulatory agent for pDCs and may be applied for the treatment of pDCs-related autoimmune diseases. [ABSTRACT FROM PUBLISHER]

The pyrolysis characteristics of blended cyclohexane and benzene mixture are investigated under supercritical pressure. The experimental results show that cyclohexane pyrolysis is greatly easier than thermal cracking of benzene, and the addition of cyclohexane can significantly promote the benzene pyrolysis, while the thermal cracking of cyclohexane itself is weakened by the addition of benzene. A simulation of the blended fuel is carried out by using Chemkin program, indicating that the chemical heat sink of cyclohexane pyrolysis can account for nearly 50% of its total heat absorption capacity, while benzene is inactive in thermal cracking process. [ABSTRACT FROM AUTHOR]

Designing and preparing a biomass-based monomer with fully biomass content is of great significance for achieving sustainability, which is in line with the target of Carbon neutrality and Carbon peak. In this work, an allyl compound (FDEU) was designed and synthesized derived from eugenol (Eu) and 2,5-furandicarboxylic acid (FDCA), and the biomass content of FDEU was as high as 100%. Two thiol-ene crosslinked polymers (TCPs), FDEU/4SH and FDEU/3SH, were prepared via solvent-free UV-light thiol-ene click reaction. The curing behavior and combination properties which include thermal properties, thermal mechanical properties, mechanical properties, and thermal stability of FDEU/4SH and FDEU/3SH were systematically investigated. The results showed that FDEU/4SH and FDEU/3SH had similar curing reactivity, and FDEU/4SH exhibited better thermal resistance, modulus, and strength. In particular, the glass transition temperature (T gDMA) of FDEU/4SH was 66.6 °C. Additionally, the tensile strength of FDEU/4SH was (56.2 ± 2.3) MPa; and tensile modulus of FDEU/4SH was (1.4 ± 0.2) GPa. Moreover, FDEU/4SH exhibited excellent thermal stability without obvious weight loss (T d5%) of 311.5 °C. The factor behind these excellent comprehensive properties of FDEU/4SH is its well-designed chemical structure of FDEU, which not only has 100% of biomass content but also has a rigid aromatic structure and furan ring. • A fully biomass-based allyl compound was synthesized from eugenol and crops. • Two thiol-ene crosslinked polymers were prepared by thiol-ene click reaction. • FDEU/4SH exhibited higher T g , tensile strength and modulus. • FDEU/4SH showed high thermally stability without obvious weight loss up to 311.5 °C. [ABSTRACT FROM AUTHOR]

A further phytochemical investigation of the whole plants of Actaea vaginata afforded two new cycloartane triterpenoid saponins, (20 S *,24 R *)-15 α ,16 β -diacetoxy-20,24-epoxy-9,19-cyclolanostane-3 β ,25-diol-3-O- β - d -xylopyranoside (1) and (20 S)-15 β ,16 β -diacetoxy-18,20-epoxy-3 β ,25-diol-24-oxo-9,19-cyclolanostan-3-O- β -D-xylo-pyrano-syl-25-O- β - d -glucopyranoside (2), together with four known compounds (3 – 6). Their structures were established on the basis of extensive analysis of NMR and HRESIMS data as well as by comparison with the reported data in the literature. All the isolates were evaluated for their cytotoxic activities against human hepatocellular carcinoma HepG2 cell line. Compounds 1 and 2 exhibited weak cytotoxicity with IC 50 values of 36.10 and 27.39 μM, respectively. In addition, beesioside I (6) was found to significantly inhibit proliferation and induce apoptosis in HepG2 cells. A closer examination of underlying mechanism revealed that beesioside I could increase the levels of ROS and caspase-3 and promote phosphorylation of JNK in the JNK signaling pathway. Molecular modeling studies also shed further light on how beesioside I interacted with the key protein kinase. [Display omitted] • Six cycloartane triterpenoid saponins including two new ones isolated from Actaea vaginata. • New compounds exhibited weak cytotoxicity against HepG2 cells. • Beesioside I was found to induce apoptosis in HepG2 cells. • Beesioside I could induce apoptosis through ROS/caspase-3/JNK signaling pathway. • Molecular modeling of beesioside I with JNK was studied. [ABSTRACT FROM AUTHOR]

To enlarge the knowledge about the control methods of pore size of phenolic porous material and to know the effect of pore size on its mechanical property, experiments were carried out. On the basis of the theory of bubble nucleation, large stirring speed can overcome the surface energy of bubble formation and the nucleating agent can provide a large number of nucleation sites for foaming system. We adopted the methods of accelerating the stirring rate and adding nucleating agent to improve bubble nucleation. Pore size, size distribution and the effects of stirring speed and nucleating agent concentration on them were investigated by scanning electron microscope and computerized image analysis program. Results showed that with the increase of stirring speed, the mean pore size decreases from 246 to 138 µm and the structural homogeneity of phenolic porous material was improved obviously. The nucleating agent has a great effect on the pore structure and optimal amount (5%) at which the pore size is small in level of micrometer and has a good distribution. In addition, the compression testing was carried out by Universal Testing Machine and the test results suggested that the change of micrometer pore structure improves the compression strength of porous material effectively. [ABSTRACT FROM AUTHOR]