TiO2 pillared montmorillonite (T/M) modifiers have been studied to alleviate the aging of asphalt pavement and degrade automobile exhaust, but the photocatalytic activity of ordinary TiO2 is not good ...enough. In this study, in order to improve the photocatalytic performance of T/M, different metal (Ce, Cu, Fe) doped modifiers were prepared based on T/M. Metal doped TiO2 pillared montmorillonite was prepared by the sol-gel method. The modifier was characterized by X-ray diffraction (XRD) and an Ultraviolet visible (UV-Vis) spectrophotometer. The results show that TiO2 with different metal ions successfully entered into the layer of organic montmorillonite (OMMT) to form a pillared structure. Compared with the undoped TiO2 pillared montmorillonite (T/M), the optical absorption edge of the metal doped TiO2 pillared montmorillonite has an obvious red shift. In addition, the influences of the different content of modifiers on the properties of the original bitumen and catalytic capacities for automobile exhaust were also investigated. The results show that Ce doped TiO2 (Ce-T/M) pillared montmorillonite has the best improvement in high temperature performance and ultraviolet (UV) resistance of bitumen. In the experiment of automobile exhaust degradation, the degradation law of NO and HC showed Cu-T/M > Ce-T/M > Fe-T/M > T/M. These three kinds of metal ions can effectively improve the photocatalytic degradation efficiency of T/M.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Mammalian cytosolic thioredoxin reductase (TrxR1) serves as an antioxidant protein by transferring electrons from NADPH to various substrates. The action of TrxR1 is achieved via reversible changes ...between NADPH-reduced and non-reduced forms, which involves C-terminal selenolthiol/selenenylsulfide exchanges. TrxR1 may be released into extracellular environment, where TrxR1 is present mainly in the non-reduced form with active-site disulfide and selenenylsulfide bonds. The relationships between extracellular TrxR1 and tumor metastasis or cellular signaling have been discovered, but there are few reports on small-molecule compounds in targeted the non-reduced form of TrxR1. Using eight types of small-molecule thiol-reactive reagents as electrophilic models, we report that the selenenylsulfide bond in the non-reduced form of TrxR1 functions as a selector for the thiol-reactive reagents at pH 7.5. The non-reduced form of TrxR1 is resistant to hydrogen peroxide/oxidized glutathione, but is sensitive to certain electrophilic reagents in different ways. With 5,5'-dithiobis-(2-nitrobenzoic acid) (DTNB) and S-nitrosoglutathione (GSNO), the polarized selenenylsulfide bond breaks, and selenolate anion donates electron to the dynamic covalent bond in DTNB or GSNO, forming TNB-S-Se-TrxR1 complex or ON-Se-TrxR1 complex. The both complexes lose the ability to transfer electrons from NADPH to substrate. For diamide, the non-reduced TrxR1 actually prevents irreversible damage by this oxidant. This is consistent with the regained activity of TrxR1 through removal of diamide
dialysis. Diamide shows effective in the presence of human cytosolic thioredoxin (hTrx1), Cys residue(s) of which is/are preferentially affected by diamide to yield disulfide, hTrx1 dimer and the mixed disulfide between TrxR1-Cys497/Sec498 and hTrx1-Cys73. In human serum samples, the non-reduced form of TrxR1 exists as dithiothreitol-reducible polymer/complexes, which might protect the non-reduced TrxR1 from inactivation by certain electrophilic reagents under oxidative conditions, because cleavage of these disulfides can lead to regain the activity of TrxR1. The details of the selective response of the selenenylsulfide bond to electrophilic reagents may provide new information for designing novel small-molecule inhibitors (drugs) in targeted extracellular/non-reduced TrxR1.
The syntheses of a zwitterionic base‐stabilized digermadistannacyclobutadiene and tetragermacyclobutadiene supported by amidinates and low‐valent germanium amidinate substituents are described. The ...reaction of the amidinate GeI dimer, LGe:2 (1, L=PhC(NtBu)2), with two equivalents of the amidinate tin(II) chloride, LSnCl (2), and KC8 in tetrahydrofuran (THF) at room temperature afforded a mixture of the zwitterionic base‐stabilized digermadistannacyclobutadiene, L2Ge2Sn2L′2 (3; L′=LGe:), and the bis(amidinate) tin(II) compound, L2Sn: (4). Compound 3 can also be prepared by the reaction of 1 with LArSnCl (5, LAr=tBuC(NAr)2, Ar=2,6‐iPr2C6H3) in THF at room temperature. Moreover, the reaction of 1 with the “onio‐substituent transfer” reagent 4‐NMe2‐C5H4NSiMe3OTf (8) in THF and 4‐(N,N‐dimethylamino)pyridine (DMAP) at room temperature afforded a mixture of the zwitterionic base‐stabilized tetragermacyclobutadiene, L4Ge6 (9), the amidinium triflate, PhC(NHtBu)2OTf (10), and Me3SiSiMe3 (11). X‐ray structural data and theoretical studies show conclusively that compounds 3 and 9 have a planar and rhombic charge‐separated structure. They are also nonaromatic.
Heavy elements: Zwitterionic base‐stabilized digermadistannacyclobutadiene (1) and tetragermacyclobutadiene (2) were synthesized by simple procedures (see scheme). X‐ray structural data and theoretical studies show that these compounds have a planar and rhombic charge‐separated structure. They are also nonaromatic.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Marine sourced clay minerals and organic matter enrichment as clay-organic nanocomposites within shale has attracted attention because of their changeable surface areas, nanoporosity, and methane ...adsorbability. Here marine shale samples were used to investigate the characteristics of clay-organic nanocomposites and their impact on gas adsorption response. The results show that organic nanolayers mainly occur as nanometer intercalations with clay nanolayers. High-resolution scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images provide direct evidence of the parallel aligned clay-organic nanocomposites with an approximate thickness of each organic and clay nanolayer and the positive correlations between their morphology, occurrence, and relative content. However, such clay-organic interactions are significantly damaged by structural deformation, accompanied by a weakening in gas adsorption capacity. We suggest that the naturally occurring structures that hydrocarbon molecules are attached or resided in fine-grained marine shales are predominantly associated with clay-organic nanocomposites, which play an important role as adsorption carriers. Moreover, the clay-organic association may be an effective mechanism of gas adsorption. These observations and investigations could challenge the common perception that discrete kerogen and clay minerals are the major components for gas adsorption.
•Clay-organic nanocomposites are common in marine shales.•Features of organic/clay nanolayers and their gas sorbed capacity have been studied.•Clay-organic nanocomposites may be the significant adsorption carriers.•Clay-organic association may be an effective mechanism of gas adsorption.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•Analyze DE algorithm two key issues: parameter sensitivity and search imbalance.•A complementary mutation strategy based on complementary symmetric selection and a Gaussian distribution mutation is ...proposed.•Data fusion-based parameter adaptation method proposed for parameter rationalization.•A novel variant of DE called DACDE is designed and results shown competitive edge.
As an excellent optimization algorithm widely used to solve various practical problems, differential evolution (DE) algorithm has few parameters, yet its performance is significantly affected by these parameters. To address this issue, this paper presents a novel variant of DE called DACDE, which utilizes data fusion-based parameter adaptation and a complementary mutation strategy. Most parameter adaptation methods based on successful history only analyze the mean of parameters and ignore their degree of dispersion. In DACDE, the successful parameter distribution is recorded and described by both the mean and variance. Data fusion is then used to combine records and generate an estimated distribution, which is applied to a Gaussian distribution to generate new parameters. Inspired by opposition-based learning, we introduce a complementary mutation strategy. This strategy employs a symmetric selection mechanism to adapt to the varying search abilities required by the algorithm at different stages. The new variant is verified on 32 single-objective functions from CEC 2011 and 2014 benchmark suites, and the results show that DACDE is competitive compared to other 29 evolutionary algorithms.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Display omitted
•Double single atoms FeMo@CoNi-OH/Ni3S2 is obtained by in situ epitaxial growth.•FeMo@CoNi-OH/Ni3S2 shows high activity to HER in wide pH range and OER in alkaline.•Different ...electronegativity of Fe and Mo leads to charge rearrangement in catalyst.•The synergies between Fe and Mo enhances OWS performance of FeMo@CoNi-OH/Ni3S2.
The limitations of single-atom catalysts (SACs) hinder their application in wide-pH range of hydrogen evolution reaction (HER) and overall water-splitting in alkaline solution. Herein, we fabricate a rod-like Ni3S2 material wrapped by single-atom Fe-Mo co-modified CoNi-based nanosheets (FeMo@CoNi-OH/Ni3S2). The introduction of Fe-SAs and Mo-SAs into CoNi-hydroxyl compounds effectively changes their electronic structure and enhances their conductivity, thereby improving HER and OER performance. FeMo@CoNi-OH/Ni3S2 catalyst endows HER with overpotentials of 89, 176 and 177 mV in alkaline, acidic and neutral solutions, respectively, as well as good oxygen evolution reaction (OER) performance with 160 mV in alkaline to achieve 10 mA cm−2. The combination of the experiments and theoretical calculations reveals that the synergistic effect of Mo-SAs with Fe-SAs effectively reduces the intermediate energy barrier of the water dissociation step. This work contributes to the understanding of the catalytic mechanisms of dual single-atomic active sites in HER and OER processes.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Substituting oxygen evolution reaction (OER) by hydrazine oxidation reaction (HzOR) is a very efficient energy-saving strategy for water electrolysis. Therefore, exploring low-cost and efficient ...catalysts for HzOR and hydrogen evolution reaction (HER) is very significant to address the great challenge for hydrogen production. Herein, a series of vanadium-cobalt bimetal-organic frameworks Vx-Co-MOFs: x represents the mass fraction of V element: V/(V+Co) are synthesized through a one-pot hydrothermal method. The V41.7wt%-Co-MOF exhibits excellent multifunctional catalytic activity. The overall hydrazine splitting (OHzS) delivers 10 mA cm−2 at an ultralow cell voltage of 0.21 V. The superior performance can be ascribed to that the presence of cobalt-vanadium bimetals, which leads to the lattice disorder, an increase in specific surface area and mesoporous structure in V41.7wt%-Co-MOF, thus ensuring the exposure of more active sites. Particularly, the in-situ Raman test indicates that V41.7wt%-Co-MOF is partially converted into Co(OH)2 in the process of electrolysis to form a heterostructure. DFT calculations further show the charge transfer between Co and V, along with the good synergy between V-Co-MOF and Co(OH)2 improves the HER and HzOR performance of V41.7wt%-Co-MOF. This study provides a promising Co-V based catalyst for energy saving hydrogen production.
V41.7wt%-Co-MOF metal compound as bifunctional catalyst for effective hydrogen production with hydrazine-assisted. Display omitted
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Electrochemical reduction of CO2 to multi-carbon products is very attractive yet particularly challenging due to the low efficiency of C-C coupling over currently used electrocatalysts. In this work, ...we report a dual-atom catalyst (Cu2/NC) capable of selectively promoting electro-reduction of CO2 to C2H4. The Faradaic efficiency of CO2-to-C2H4 over the Cu2/NC is up to ∼34.9% with a current density of 33.6 mA·cm−2. By contrast, its Cu single-atom counterpart only generates CO without forming C2H4. The density functional theory (DFT) calculations reveal that the Cu-Cu sites largely promote the adsorption of *CO and reduce the energy barrier of C-C coupling between the adsorbed *CO relative to that of the single Cu sites, which accounts for the high C2H4 selectivity of the Cu2/NC.
Display omitted
•Highly efficient Cu dual-atom catalysts were prepared to catalyze CO2RR.•Compared with Cu single-atom catalyst, dual-atom catalyst was more favorable to reduce CO2 to multi-carbon product C2H4.•DFT calculations revealed that the energy barrier of C-C coupling was largely reduced on the dual Cu catalysts.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Display omitted
•A novel additive, 2,2,2-Trifluoroethyl trifluoroacetate, was found can construct a flaky LiF-rich SEI layer.•Using additive ensures a long lifespan up to 750 h in Li|Li cell and a ...higher CE of 99.7% in Li|Cu cell.•A stable cycling performance and better rate capability of LMBs is achieved.
As the holy grail anode, lithium (Li) metal has attracted considerable interest in developing next-generation high-energy–density batteries. However, Li dendrites due to the poorly protected solid electrolyte interphase (SEI) during the Li plating process largely limit the Li application. Here, we report an effective electrolyte additive, i.e., 2,2,2-Trifluoroethyl trifluoroacetate (2,2,2-TFTF) as highly efficient inhibitor against growth of Li dendrites by facile mediation of SEI layer. DFT calculations and a series of characterization results indicate that the additive greatly favors formation of more protective SEI layer on the Li anode and homogeneous Li deposition. Strikingly, with 4% additive, the Li|Li cell showed a long cycle life of 750 h and the Li|Cu cell afforded an ultrahigh Coulombic efficiency (CE) of 99.7%. Moreover, the Li|LFP cell with 4% additive exhibited high-capacity retention and better rate performance, especially at 5C. The additive 2,2,2-TFTF offers a nontraditional option for high-performance lithium metal batteries with simplicity and saving.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
AbstractThis study aimed to explore the interaction and antiaging characteristics of composite phase change materials in asphalt for long-term temperature adjustment of asphalt pavement. First, the ...epoxy resin/phase change materials (E-PCMs) modified asphalt binders were prepared by the melt blending method, and their microscopic, rheological, and temperature adjustment properties were tested. Finally, the long-term performance of the modified asphalt binders was evaluated by simulated aging. The results show that E-PCMs are well dispersed in the modified asphalt binders. E-PCMs can improve the temperature sensitivity and high-temperature stability of asphalt binders, and they could reduce the fluidity of asphalt molecules at high-temperature. The extreme temperature of the E-PCMs–modified asphalt binders can be reduced by 10.4°C and have an excellent temperature adjustment effect. The aged modified asphalt binders still have excellent temperature adjustment properties, and the survival rate of phase change enthalpy is 88%. E-PCMs could also prevent the oxidative aging of asphalt molecules and reduce the adverse effects of the photothermal environment on asphalt. It provides reference and basis for the large-scale promotion and application of temperature-adjusting pavement, which reduces the temperature disease of asphalt pavement and the near-surface thermal environment.
PDF
