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Polyoxometalates (POMs) as molecule-based metal oxides have exhibited significant application in catalysis and materials science, but the synthesis of pristine POM nanomaterials still remains a challenge. In this work, we find a novel strategy of concentration-induced self-assembly for gaining pristine POM nanorods AgxH3−xPMo12O40 (denoted as AgHPMo12), which are synthesized only from both POMs and silver ion Ag+ in an aqueous solution at room temperature. The controllable concentrations of the cationic and anionic components in the aqueous solution become the critical factor for the successful synthesis. In addition, the photoelectric properties of AgHPMo12 nanorods were investigated as compared to those of AgHPMo12 particles, indicating a superior photoelectric performance of AgHPMo12 nanorods to AgHPMo12 particles. Furthermore, AgHPMo12 nanorods/phthalocyanine heterojunction photocatalysts were prepared for evaluating photocatalytic degradation of tetracycline hydrochloride, showing an efficient photocatalytic performance due to the advantages of the nanorods and type II heterostructure.

The structures of two-dimensional (2D) self-assembled molecular networks formed by a series of perylene bisimide (PBI) derivatives were investigated by scanning tunneling microscopy (STM). By introducing different functional groups to the PBI rings, we successfully built a different self-assembled molecular network on the liquid-solid interface. When the substituent is propanol, PBI is aligned in lines. When we introduced either an ester group or an amide group to the PBI compounds, they tended to form dimers and trimers. Especially, the PBI with the amide groups can form a 2D porous molecular network by hierarchy self-assembly. The 2D porous molecular network has a great potential to be the host molecule for the accommodation of a guest molecule, coronene (COR), and the structure of the 2D porous molecular network can be tuned by varying the concentration. The density functional theory calculations were also performed to disclose the mechanisms involved.

Lactobacillus acidophilus is an important probiotic. The β-glucosidase produced by L. acidophilus GIM1.208 can transform quercetin glycosides of Rosa roxburghii Tratt to release quercetin and improve the functional activity of raw materials. Understanding the interaction and the characteristics of the two will lay a theoretical foundation for the site-directed transformation and functional application of the catalytic active site of enzymes. In our study, using the heterologously expressed and highly stable, purified L. acidophilus GIM1.208 BGL as the strain, the representative quercetin in β-glucosidase and Rosa roxburghii Tratt was preliminarily predicted and explored using ultraviolet-visible absorption spectroscopy. Fluorescence spectroscopy combined with molecular docking was used to determine the interaction characteristics of the glycoside substrates, rutin (Rut) and isoquercitrin (Iso). Results from molecular docking showed that Asp159, Arg56, Iso294, Phe292, and Gly25 were the main residues of β-glucosidase and Rut. Arg56 was found to be the most crucial residue of β-glucosidase and isoquercitrin; the interaction between Rut and Iso and β-glucosidase was mainly driven by hydrogen bonding. The combined free energy of β-glucosidase and Iso was found to be -182.10 kcal/mol, while that of β-glucosidase and Rut was -32.37 kcal/mol. The results of fluorescence spectroscopy showed that the fluorescence intensity of β-glucosidase decreased with an increase in Rut and Iso concentrations. This interaction made β-glucosidase quench endogenous fluorescence, which was static quenching. The binding constants of Rut and Iso with β-glucosidase were determined to be 0.50×107 and 0.31×107 L/mol, respectively, indicating that rutin had a stronger affinity when interacting with β-glucosidase. These findings were consistent with our prediction results determined using molecular docking studies.

Perylene diimides (PDIs) belong to an important class of photoactive materials due to their excellent electrical and photophysical properties. Highly controlled aggregation and self-assembly attributed to the large π-conjugated aromatic scaffold have led to a variety of optoelectronic applications. In this manuscript, two PDI derivatives PDI-1 and PDI-2 with unsymmetrical N-substitution of amine and ester-bridge were designed and synthesized. These two compounds were characterized by NMR, Fourier transform infrared (FT-IR), and high-resolution mass spectrometry (HRMS). The photophysical properties were studied by UV–Vis absorption and fluorescence spectroscopy. Cyclic voltammograms of PDI-1 and PDI-2 were investigated and HOMO and LUMO energy levels of both two PDIs were estimated as −6.2 and −3.9 ​eV, respectively. Thermal properties were also studied by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). PDI-1 was assembled into nanotubes while PDI-2 was assembled into nanobelts respectively, via a reprecipitation method. PDI-1 and PDI-2 show good potential application in organic devices such as solar cells, organic field-effect transistors (OFETs) and so on.

Background and Objectives: Chronic kidney disease (CKD) and acute kidney injury (AKI) increase the risk of serious disease and mortality in severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)-infected patients. This study evaluated the occurrence and outcome of AKI in CKD and non-CKD patients infected with SARS-CoV-2. Subjects and Methods: We retrospectively analyzed the medical records of 845 patients with SARS-CoV-2 infection regarding the occurrence and outcome of AKI in a coronavirus disease-2019 (COVID-19)-designated hospital in Wuhan, China, from December 31, 2019, to March 20, 2020. Results: Of the 845 COVID-19 patients, 91 had CKD and 754 had no CKD (non-CKD), of whom 22 and 14 developed AKI, respectively. Finally, 36 patients were included in the analysis. Older patients and those with cardiovascular or cerebrovascular diseases were more likely to develop AKI. More CKD patients progressed to critical illness (72.73%) than non-CKD patients (57.14%), but the degree of AKI in CKD patients was lesser than that in non-CKD patients. Higher urea nitrogen, creatinine, and proteinuria levels were observed in CKD patients. More non-CKD patients were treated with human albumin than CKD patients. The survival probability of CKD patients was lower than that of non-CKD patients, but it was not statistically significant. Conclusion: There were significant differences in the incidence rate of AKI after SARS-CoV-2 infection between CKD and non-CKD patients, and the clinical manifestations and treatments of AKI also differed. These results highlight the necessity of variable treatment methods for optimal clinical management.

Supported palladium and palladium alloy were proved to be active catalysts for the oxidative esterification reaction of methacrolein with methonal to methyl methacrylate. Here we synthesized two types of structurally supported palladium alloy catalysts with ordered or disordered Pd3Pb intermetallic crystals by impregnation-reduction method as well as high temperature heat treatment. Importantly, the catalyst with disordered Pd3Pb crystals had 89% conversion for methylacrolein and 79% selectivity for methyl methacrylate, showing obvious higher activity than the catalyst with ordered Pd3Pb crystals. The morphology, metal arrangement and electron effect of the catalyst were analyzed by XRD, TEM and XPS. It was confirmed that more active sites and strong electron transfer between metals were the reasons for the excellent performance of the disordered catalyst. This study provides theoretical guidance for the further study of Pd-based catalysts for the oxidative esterification of methacrolein to methyl methacrylate.

In this work, we have developed a highly efficient approach to fabricating graphene oxide (GO) functionalized with melamine molecule by chemical crosslinking. The melamine-functionalized graphene oxide (MEL-GO) was characterized by FT-IR, Raman, XRD TGA, XPS, SEM and TEM. Using monoethanolamine (MEA) aqueous solution as the basic absorbent, The absorbance performance of CO 2 in the (MEL-GO)+MEA+H 2 O solid-liquid hybrid absorbent for different mass concentrations of MEL-GO in 30 wt% MEA aqueous solution was investigated. The solubility of CO 2 in (MEL-GO)+MEA+H 2 O absorbents is much larger than that in 30 wt% MEA aqueous solution. Moreover, when the partial pressure of CO 2 continues to go up, the solubility of CO 2 was obviously increased with increasing mass concentrations of MEL-GO. The results suggest that MEL-GO is beneficial to enhance the solubility of CO 2 in MEA aqueous solution.

Exosomes derived from mesenchymal stem cells (MSCs) are known to participate in myocardial repair after myocardial infarction (MI), but the mechanism remains unclear. Here, we isolated exosomes from adipose-derived MSCs (ADSCs) and examined their effect on MI-induced cardiac damage. To examine the underlying mechanism, H9c2 cells, cardiac fibroblasts, and HAPI cells were used to study the effect of ADSC-exosomes on hypoxia-induced H9c2 apoptosis, TGF-β1-induced fibrosis of cardiac fibroblasts, and hypoxia-induced macrophage M1 polarization using qRT-PCR, western blot, ELISA, immunohistochemistry, immunofluorescence and flow cytometry. ADSC-exosome treatment mitigated MI-induced cardiac damage by suppressing cardiac dysfunction, cardiac apoptosis, cardiac fibrosis, and inflammatory responses in vitro and in vivo. In addition, ADSC-exosome treatment promoted macrophage M2 polarization. Further experiments found that S1P/SK1/S1PR1 signaling was involved in the ADSC-exosome-mediated myocardial repair. Silencing of S1PR1 reversed the inhibitory effect of ADSC-exosomes on MI-induced cardiac apoptosis and fibrosis in vitro. ADSC-exosome-induced macrophage M2 polarization was also reversed after downregulation of S1PR1 under hypoxia conditions, which promoted NFκB and TGF-β1 expression, and suppressed the MI-induced cardiac fibrosis and inflammatory response. In sum, these results indicate that ADSC-derived exosomes ameliorate cardiac damage after MI by activating S1P/SK1/S1PR1 signaling and promoting macrophage M2 polarization.

To improve pepper powder product flavor, headspace gas chromatography-ion mobility spectrometry (HS-GC-IMS) was used to detect flavor substances in pepper powder, including dried pepper powder, baked pepper powder (BPP) and Maillard treated pepper powder (MTPP). Fifty-three flavor compounds were identified, mainly comprising alcohols, esters, aldehydes, ketones, etc. Volatile organic compound type and content in BPP and MTPPs differed from dried pepper powder, with more types present in MTPPs than BPP. Partial least-squares discrimination analysis and principal component analysis were employed to identify relationships between flavor substances and sample type, and evaluate different exogenous Maillard's flavoring reaction affects. Dried pepper powder was positively related with most flavor compounds, and Maillard reaction substrate combinations of lysine-xylose, lysine-lactose, valine-fructose, and valine-xylose exhibited high correlation with several characteristic compounds, whereas no characteristic compounds exhibited high correlations in BPP. Thus, adding exogenous Maillard reaction substrate offers a mechanism to improve BPP flavor quality.

A novel dual-responsive fluorescence probe 6 was constructed by introducing a dipicolyamine moiety on the BODIPY-based skeleton via Sonogashira coupling reaction and confirmed by 1H NMR, 13C NMR, elemental analysis and high-resolution mass spectroscopy (HRMS). The present probe 6 exhibited high selectivity and sensitivity toward Cu2+ and Ni2+ detection over other competitive metal ions by fluorescence quenching phenomena, respectively. In addition, the detection limits (DLs) for Cu2+ and Ni2+ were calculated to be as low as both 0.1 μM respectively, which were lower than the maximum allowable level of the World Health Organization (WHO) limit for the drinking water. The stoichiometric ratio of the probe 6 toward the Cu2+ or Ni2+ ions was determined to be 1:1 according to the result of the Job's plot and HRMS analysis. These results indicated that probe 6 can be used as a selective ‘‘turn-off’’ fluorescent sensor for the detection of Cu2+ and Ni2+.

Modification of semiconductor materials by polyoxometalates (POMs) is a promising strategy for increasing their photoelectrocatalytic (PEC) activity. In this work, we synthesized POM-modified CdS composite nanocrystals based on three kinds of Keggin-type mixed-addendum Mo/W POMs (Ag3PMo3W9O40, Ag3PMo6W6O40, and Ag3PMo9W3O40). This is the first report on the semiconductor properties of the three Keggin-type mixed-addendum Mo/W POMs. Their PEC performances were studied by transient photocurrent responses, electrochemical impedance spectroscopy, and PEC oxidation of As(III) to As(V). The PEC performances of POM-modified CdS composite nanocrystals (CdS/Ag3PMo3W9O40, CdS/Ag3PMo6W6O40, and CdS/Ag3PMo9W3O40) were superior to the performance of pure CdS nanocrystals. CdS/Ag3PMo3W9O40 composite nanocrystals exhibited the highest efficiency for the PEC oxidation of As(III) to As(V), which was about 85% higher than that of the pure CdS nanocrystals. The present study provides insight into developing novel composite nanocrystals with Keggin-type mixed Mo/W POMs for efficient PEC oxidation.

The molecular structures of ionic liquids at interfaces play a crucial role in determining their chemical activities in applications. In situ X-ray photoelectron spectroscopy (XPS) was used to track the evolution of X-ray irradiation-induced chemical reactions in a series of ionic liquids ([Cn mim][AuCl4 ]; n=4, 6, 8, 10) on the Si (111) single-crystal surface. Analyses of microstructure and chemical bonding based on the XPS results indicated that reactions occurred at the vapor/liquid interfaces of the ionic liquids. The time-resolved XPS spectra revealed that with increasing irradiation time, the intensity of the peak corresponding to trivalent Au anion decreased for the four ionic liquids as Au was continually reduced to a lower chemical state and finally converted to gold nanoparticles. The rate and conversion of the reaction were associated with the length of the alkyl chain of the ionic liquids cation. Molecular dynamics simulations further revealed that the alkyl chain of the cation in the ionic liquids was oriented towards the vacuum environment at the vapor/liquid interface. Our results provide a real-time atomic-scale experimental evidence of organic reactions at the vapor/liquid interfaces of ionic liquids. The findings are important for understanding the roles of ionic liquids in catalysis, separation, electrochemistry, functional materials, and so on.

The controlled dissolution of microdroplets on a supporting substrate is an effective approach that can be used to tune the assembled microstructure of basic units suspended within the droplet. In this work, we studied the self-assembly of two-dimensional graphene oxide (GO) nanosheets driven by the dissolution of a microdroplet situated at the interface between a solid substrate and the surrounding liquid phase. We found that although uniform microstructures form at the liquid-liquid interface of the droplets, the contact between the droplet and the substrate can give rise to a variety of different morphologies near the base of the droplet. In particular, pinning effects at the boundary of the dissolving droplet on the substrate lead to non-spherical GO assemblies. The results in this work demonstrate the possibility that tailored three-dimensional architectures of nanosheets assembled in a dissolving droplet may be achieved through control of the wetting properties of the droplet on the supporting substrate.

Two imidazolium-based ionic liquids (ILs), i.e. [Bnmim][BF4] (1-benzyl-3-methylimidazolium tetrafluoroborate) and [Bmim][AuCl4] (1-butyl-3-methylimidazolium chloroauric acid), were adsorbed on the outer surface of multi-walled carbon nanotubes (MWCNTs) via a physical method. In order to understand the molecular packing of ILs immobilized on the MWCNTs surfaces, composite samples with different weight ratios of ILs were characterized by using X-ray photoelectron spectroscopy (XPS), differential scanning calorimetry (DSC), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). It was found that the rings of imidazolium cations of ILs are nearly parallel to the MWCNTs surfaces, and the packing orientation is determined by the substituent groups on the imidazolium-ring. Both the anions ([BF4]− and [AuCl4]−) occupy an adjacent area to the imidazolium cation to form a neutral surface layer. Furthermore, for the immobilized ILs, the melting point (Tm) of [Bmim][AuCl4] rises slightly, while the Tm of [Bnmim][BF4] gets depressed. The molecular rearrangement and the melting point change of the immobilized ILs result from the complex interfacial interactions between the ILs and the MWCNTs surfaces.

Manipulating the way a droplet shrinks by evaporation or dissolution is an effective approach for assembling dissolved nanomaterials. In this work, we investigate the dissolution dynamics of a submicroliter sessile droplet of electrolyte aqueous solution and of graphene oxide suspension immersed in a binary mixture of solvents, among which one is miscible and the other is immiscible with water (i.e., an Ouzo system). Our measurements reveal an interesting two-stage dissolution of the droplet: a fast initial stage and a slow second stage. The duration of the first stage is longer at a lower temperature, leading to a counterintuitive result that the dissolution completes faster at reduced temperature. The presence of graphene oxide in the droplet dramatically alters the dissolution dynamics, possibly due to its enrichment at the droplet surface. The finding from this work provides useful guideline for designing conditions to pack nanomaterials by dissolving droplets, especially for those temperature sensitive components.

This chapter contains a tabular compilation of eutectic temperature and phase equilibrium of n -butyl-4 -methylpyridinium tosylate mixtures.

This chapter contains a tabular compilation of volumetric, transport properties and refractive index of 1-butyl-2,3-dimethylimidazolium tetrafluoroborate mixtures.

This chapter contains a tabular compilation of volumetric, transport and other properties of 1-butyl-3-methylimidazolium thiocyanate mixtures.

This chapter contains a tabular compilation of phase equilibrium of n -butyl-4-methylpyridinium bis[(trifluoromethyl)sulfonyl]imide mixtures.

This chapter contains a tabular compilation of volumetric properties, phase equilibrium and conductivity of 1-butyl-3-methylimidazolium dicyanamide mixtures.

This chapter contains a tabular compilation of phase equilibrium and activity coefficient of 1-methyl-1-octylpyrrodinium bis((trifluoromethyl)sulfonyl)imide mixtures.

This chapter contains a tabular compilation of selectivity and capacity of n-acryloyloxypropyl-N-methylimidazolium bromide mixtures.

This chapter contains a tabular compilation of solubility and diffusivity of 1-butyl-3-methylpyridinium bis((trifluoromethyl)sulfonyl)imide mixtures.

This chapter contains a tabular compilation of volumetric properties, refractive index, heat capacity and derived properties of pyrrolidinium nitrate mixtures.

This chapter contains a tabular compilation of selectivity, capacity and phase equilibrium of triethylsulphonium bis[(trifluoromethyl)sulfonyl]imide mixtures.

This chapter contains a tabular compilation of cloud point of 1-hydroxyethyl-3-methylimidazolium bis((trifluoromethyl)sulfonyl)imide mixtures.

This chapter contains a tabular compilation of volumetric properties of 1-amyl-3-methylimidazolium hexafluorophosphate mixtures.

This chapter contains a tabular compilation of excess enthalpy, phase equilibrium and transport properties of choline glycolate (2-hydroxyethyl-trimethylammonium 2-hydroxyethanoate) mixtures.

This chapter contains a tabular compilation of capacity, selectivity, activity coefficient and excess molar enthalpy of 1-butyl-1-methyl-pyrrolidinium trifluoromethanesulfonate mixtures.

This chapter contains a tabular compilation of volumetric, thermodynamic and other properties of 1-hexyl-3-methylimidazolium bis((trifluoromethyl)sulfonyl)imide mixtures.

This chapter contains a tabular compilation of volumetric properties of 1-methyl-3-ethylimidazolium chloride mixtures.

This chapter contains a tabular compilation of volumetric properties of tetrabutyl phosphonium valinate mixtures.

This chapter contains a tabular compilation of volumetric, transport, and other properties of ethyl pyridinium ethylsulfate mixtures.

This chapter contains a tabular compilation of eutectic temperature of tetra(n-butyl)phosphonium tosylate mixtures.

This chapter contains a tabular compilation of phase equilibrium of 1-ethyl-3-methylimidazolium dicyanoamide mixtures.

This chapter contains a tabular compilation of volumetric properties and surface tension of ethyl(2-hydroxyethyl)dimethylammonium dicyanamide mixtures.

This chapter contains a tabular compilation of volumetric, transport properties and phase equilibrium of 1-butyl-3-methylimidazolium nitrate mixtures.

This chapter contains a tabular compilation of phase equilibrium, volumetric properties and surface tension of 1-hexyloxymethyl-3-methylimidazolium tetrafluoroborate mixtures.

This chapter contains a tabular compilation of activity coefficient, selectivity and capacity of 1-hexyl-3-methylimidazolium trifluoromethanesulfonate mixtures.

This chapter contains a tabular compilation of solubility and diffusivity of 1-butyl-3-methylimidazolium 1,1,2-trifluoro-2-(trifluoromethoxy) ethanesulfonate mixtures.

This chapter contains a tabular compilation of volumetric and transport properties of n-butyl pyridinium tetrafluoroborate mixtures.

This chapter contains a tabular compilation of solubility, electrical conductivity, melting point and transport properties of 1-ethyl-3-butylbenzotriazolium hexafluorophosphate mixtures.

This chapter contains a tabular compilation of phase equilibrium of 1,4-dimethylpyridinium tosylate mixtures.

This chapter contains a tabular compilation of cloud point of 1-hydroxyethyl-3-methylimidazolium hexafluorophosphate mixtures.

This chapter contains a tabular compilation of phase equilibrium of pyridinium ethoxyethylsulfate mixtures.