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Homogeneously Eu3+ doped LaOCl single crystals are firstly synthesized in a molten KCl-LiCl flux, and the well-shaped LaOCl:Eu3+ polyhedral micro-plates exhibit noticeable luminescent properties. The bulk LaOCl:Eu3+ micro-plate with a width of 1.03 μm and 1.37 μm in length shows a single crystal characteristic with the crystal face orientation of [00 1 ‾ ]. Both XRD patterns and EDS mapping indicate that the Eu3+ ions have been homogeneously doped into LaOCl lattice. LaOCl:Eu3+ nucleuses generated in molten KCl-LiCl flux at even 350 °C benefited to the decomposition of La(OH) 3 :Eu3+ precursor, and polyhedral LaOCl micro-plate is easily formed in molten KCl-LiCl salt due to the solid-ionic reaction and crystal growth. The luminescent properties of LaOCl:Eu3+ are firstly enhanced and then weakened with the increasing concentration of the doped Eu3+, 6% Eu3+ doped LaOCl:Eu3+ exhibits the best luminescent properties which can be used as a potential LED material. [ABSTRACT FROM AUTHOR]

Abstract Herein, a novel electrochemical ultrasensitive immunosensor was designed for detecting prostate-specific antigen (PSA) with three-dimensional (3D) PtCu hollow nanoframes (PtCu HNFs) as signal amplification. The highly opened PtCu HNFs were synthesized by a one-pot solvothermal method with cetyltrimethylammonium chloride (CTAC) and trishydroxymethyl aminomethane (Tris) as co-structuring directors. The architectures enlarged the loading of prostate specific antibodies (Ab) and efficiently catalyzed hydrogen peroxide (H 2 O 2) reaction, ultimately amplifying the signals. And polylysine was used to disperse PtCu HNFs, improve the biocompatibility and bind the Ab on the electrode surface. The fabricated immunosensor exhibited lower detection limit (0.003 ng mL–1, S / N = 3), and wider linear range (0.01–100.0 ng mL–1), along with the improved reproducibility, selectivity and stability for the assay of PSA. Thus, it is a desirable platform for PSA detection in clinical diagnosis and practical applications. Highlights • Uniform PtCu HNFs were synthesized by a simple solvothermal method. • Tris and CTAC acted as the co-structure-directing agents. • Polylysine can well disperse PtCu HNFs with increased biocompatibility. • PtCu HNFs was constructed for PSA immunosensor with excellent analytic performance. [ABSTRACT FROM AUTHOR]

Nanoceria was synthesized by treating cerium carbonate hydrate in a molten KOH-NaOH mixture at 200 °C. The nanoceria thus synthesized under a hydrogen atmosphere had a crystal size of 21.6 nm measured by XRD, consistent with the particle size of 23 nm measured by TEM. Raman spectra results indicated that the nanoceria produced under hydrogen had a downshift of 0.9 cm −1 from the sample synthesized in air. XPS spectra showed that the Ce 3+ fraction of the nanoceria synthesized in hydrogen was greater than that produced in air. The oxygen vacancies were formed by partial oxidization of the precursor in molten KOH-NaOH mixture. The UV–visible absorption properties of ceria synthesized under hydrogen showed a 34 nm red-shift compared with that synthesized in air. The nanoceria prepared in this work had a better catalytic property for CO oxidization than the commercial nanoceria. Results indicated that the increased Ce 3+ fraction or oxygen vacancies formed by this partial oxidization process extended the absorption edge of ceria resulting in a narrower band gap, and enhanced the catalytic activity of nanoceria. This method has proven to provide a simple and scalable method for the synthesis of high quality nanoceria. [ABSTRACT FROM AUTHOR]

For the efficient surface plasmon resonance (SPR)-based DNA assay researching, signal amplification tactics were absolutely necessary. In this work, a sensitive SPR-DNA sensor was developed by employing in situ synthesis of copper nanoparticles (CuNPs) templated by poly-T sequences DNA from terminal deoxynucleotidyl transferase (TdT)-mediated extension, and synergistically with nano-effect deposition as the mass relay. The objective of this strategy was manifold: firstly, t DNA hybridized with the optimal designed probes to active the TdT-mediated DNA extension onto the surface of SPR chip, resulted a long poly-T sequences ssDNA chain in ds DNA terminal onto surface of gold chip and characterized by SPR signal amplitudes. Secondly, copper ion (Cu 2+ ) adsorbed into the skeleton of poly-T sequences DNA, with the aid of ascorbic acid (VC) to achieve the Cu 2+ reduction, copper nanostructures (CuNPs) was synchronously generated onto the single nucleotide chain anchoring in ds DNA derivatives and the formation was featured by transmission electron micrographs (TEM) and electrochemistry. Lastly, ds DNA-complexed CuNPs (CuNPs@ ds DNA) triggered the final signal amplification via real-time conversion of the additive catechol violet (CV) into oligomer or chelation precipitation by CuNPs-tagged reporters. With the proposed setups, a precise and replicable DNA sensing platform for specific target oligo was obtained with a detection limit down to 3.21 femtomolar, demonstrating a beneficial overlapping exploitation of nanomaterials and biochemical reaction as unique SPR infrastructure. Such triple-amplification strategic setups, the possibility of various methods abutment and biocompatibility weight reactor was amassed and adapted to more biological detection field. [ABSTRACT FROM AUTHOR]

[Display omitted] • MOFs-derived Ni-Co alloy catalysts were used in NCH selective hydrogenation. • Ni-Co alloy effects facilitate CoO x reduction and increase the Co0 amounts. • Ethylenediamine favors the N -CHH formation and reduces the whole energy barriers. • Pyridinic-N favors intermediate N -CHH conversion to CHO. • Ni 1 Co 2 (1 1 1) crystal surface presents the lowest energy barrier of the α-H transfer. High-efficiency Ni-Co alloy encapsulated in N -doped carbon layer (Ni 1 Co 2 @NC-APTES) catalysts were prepared via simple Ni-Co-MOF pyrolyzation and applied in the selective hydrogenation of nitrocyclohexane (NCH) to cyclohexanone oxime (CHO). The results show that the alloy effects between Ni and Co can highly promote catalytic activity. The appropriate Ni addition can facilitate the reduction of CoO x and increase zero-valent Co (Co0) amounts. Moreover, pyridinic-N doping increases the Lewis basicity, which favors the intermediate cyclohexylhydroxylamine (N -CHH) conversion to CHO. Additionally, the in-situ DRIFT and density functional theory (DFT) calculations propose the mechanism for NCH hydrogenation in ethylenediamine (EDA) and the results show that the EDA changes the reaction path of NCH hydrogenation to CHO, prefers to form N -CHH, and significantly reduces the whole reaction energy barrier of NCH to CHO. Moreover, the Ni 1 Co 2 (1 1 1) crystal surface with the lowest d -band center and the strongest Ni-Co alloy effects presents the highest adsorption energies of H 2 and NCH, the lowest adsorption energies of H* and CHO, and the lowest energy barrier of the α -H transfer which is conducive to form the N -CHH. Under the optimum conditions, the Ni 1 Co 2 @NC-APTES gives 93.6% selectivity to CHO at 94.5% NCH conversion in EDA. [ABSTRACT FROM AUTHOR]

A highly efficient surface plasmon resonance (SPR)-based DNA assay was developed, by employing noncovalently functionalized graphene nanosheets as a substrate, and enzymatic catalysis-induced polymerization as mass relay. The objective of this strategy was manifold: first of all, to sensitize the overall SPR output by in situ optimized electrogeneration of graphene thin-film, which was characterized by atomic force microscopic topography; secondly, to regulate the self-assembly and orientation of biotinylated capture probes on nickel-chelated nitrilotriacetic acid (NTA) scaffolds, that anchored onto graphene-supported pyrenyl derivatives; and lastly, to synergize the signal amplification via real-time conversion of the additive aniline into polyaniline precipitation by horseradish peroxidase-tagged reporters. With this setup, a precise and replicable DNA sensing platform for specific targets was achieved with a detection limit down to femtomolar, thus demonstrating a beneficial exploration and exploitation of two-dimensional nanomaterials as unique SPR infrastructure. The possibility of such ″bottom-up″ architecture mounted with ″top-down″ weight reactor would be most likely extensible and adaptable to protein determinations. [ABSTRACT FROM AUTHOR]

In this work, a series of Mo/γ-Al 2 O 3 catalysts have been prepared by using Mo species enwrapping with dodecyltrimethylammonium bromide (DTAB) as the novel precursors for the hydrodesulfurization (HDS) of dibenzothiophene (DBT). The objective of this work is to get a deep insight into the effect of the Mo precursors on the size and morphology of the active phases and HDS activity. DTAB as the organic additive for the preparation of Mo precursors can dominate the nature of precursor solution and adjust the metal-support interaction so as to control the dispersion and morphology of the active phases. It is clearly shown that the addition of DTAB can effectively decrease the strong interaction between the Mo species and γ-Al 2 O 3 support and favor to tune the size and morphology of MoS 2 nanoparticles. The optimum molar ratio of DTAB/Mo is 3/5 and the corresponding catalyst shows the highest sulfidation degree with the most suitable stacking layer numbers and the shortest length of MoS 2 and thus exhibits the best HDS performance. Our work explores the important roles of organic additive to adjust the metal-support interaction and control the morphology of active phases and provides an effective precursor which can be used widely to prepare supported catalysts. [ABSTRACT FROM AUTHOR]

We explore the QCD phase diagram by constructing a holographic QCD model using the Einstein-Maxwell-Scalar system. The chiral transition is investigated by adding a probe scalar and the confinement transition is studied by adding a probe string into the system. By interpreting the black hole phase transition in the bulk spacetime as the quarkyonic transition in the dual QCD theory and introducing the bypass mechanism for the deconfinement transition, we give an explanation why chiral symmetry breaking and deconfinement transition lines coincide with each other despite their different physical origins. [ABSTRACT FROM AUTHOR]

The pursuit of more specific and sensitive response is a perpetual goal for modern bioassays. This work proposed a novel label-free strategy about redox-related mass effect based on the surface plasmon resonance (SPR) technique for ultrasensitive determination of DNA. The protocol starts with the modification of SPR gilded disk with the capture DNA ( c DNA). After the conjugation of immobilized c DNA with the target DNA ( t DNA), the hybridization chain reaction was triggered by the introduction of mutual partial complementary primers to elongate the terminal into a nanoscale duplex. As it is reported that porphyrin could intercalate into the grooves of the double-stranded DNA ( ds DNA) scaffold, multiple positive-charged Fe III meso - tetra ( N -methyl-4-pyridyl) porphine (FeTMPyP) with symmetric structure were uptaken for in situ formation of porphyrin- ds DNA complex. Given FeTMPyP a highly efficient catalysis for the peroxide reduction, its presence as a biomimetic cofactor was validated via circular dichroism and UV–vis spectroscopy, demonstrating a tight binding as well as high catalytic activity and stability. Using 4-chloro-1-naphthol as a proton donor, the catalytic reduction of H 2 O 2 would oxidize it into insoluble benzo-4-chloro-hexadienone, which simultaneously deposited on the heterogeneous interface, leading to a significant amplification in both SPR response and topological height profile. The signal increment was proportional to the concentration of t DNA, thus an ultrasensitive SPR-based DNA assay was developed with a linear range over four orders of magnitudes and a sub -femtomolar detection limit of 0.73 fM. The developed methodology exemplifies a different way of thinking about mass-sensing modes, extending conventional SPR-based DNA analysis to relevant biomedical applications. [ABSTRACT FROM AUTHOR]

Histone deacetylase (HDAC) inhibitors are an emerging class of targeted therapy against cancers. Thailandepsin A (TDP-A) is a recently discovered class I HDAC inhibitor with broad anti-proliferative activities. In the present study, we aimed to investigate the potential of TDP-A in the treatment of breast cancer. We demonstrated that TDP-A inhibited cell proliferation and induced apoptosis in breast cancer cells at low nanomolar concentrations. TDP-A activated the intrinsic apoptotic pathway through increase of pro-apoptotic protein Bax, decrease of anti-apoptotic Bcl-2, and cleavage of caspase-3 and poly (ADP-ribose) polymerase (PARP). TDP-A also induced cell cycle arrest at the G2/M phase, and promoted the production of reactive oxygen species (ROS). We have successfully encapsulated TDP-A into our recently developed disulfide cross-linked micelles (DCMs), improving its water solubility and targeted delivery. TDP-A loaded DCMs (TDP-A/DCMs) possess the characteristics of high loading capacity (>20%, w/w), optimal and monodisperse particle size (16 ± 4 nm), outstanding stability with redox stimuli-responsive disintegration, sustained drug release, and preferential uptake in breast tumors. In the MDA-MB-231 breast cancer xenograft model, TDP-A/DCMs were more efficacious than the FDA-approved FK228 at well-tolerated doses. Furthermore, TDP-A/DCMs exhibited synergistic anticancer effects when combined with the proteasome inhibitor bortezomib (BTZ) loaded DCMs (BTZ/DCMs). Our results indicate that TDP-A nanoformulation alone or in combination with BTZ nanoformulation are efficacious against breast cancer. [ABSTRACT FROM AUTHOR]

Abstract: A series of mesoporous sieves with different pore diameters and structures have been controllably synthesized by adding variable amounts of swelling agent 1,3,5-trimethylbenzene in the preparation process for SBA-15. NiMo catalysts supported by mesoporous sieves are prepared by using the newly proposed Mo-based organic–inorganic hybrid nanocrystals as precursors to load Mo and subsequently using wetness impregnation to load Ni. The hydrodesulfurization (HDS) activity of these obtained catalysts is evaluated in a continuously flowing tubular fixed-bed microreactor using 1wt% dibenzothiophene (DBT) in heptane as a model compound. The results show that HDS ratio has gradually increased as the pore diameter of supports is enlarged from 7 to 11nm with the mesostructure keeping an ordered two-dimensional hexagonal symmetry. When the structure is in the intermediate stage of structural transition from ordered hexagonal mesostructure to mesocecullar structure, HDS ratio is decreased dramatically due to the disordered and collapsed structure to block the pore channels. After the mesocecullar structure with three-dimensional open pore channels is formed which is more convenient for the molecular diffusion, HDS ratio has increased again as a result. It is concluded that both the pore size and window size connecting the adjacent pores play an important role in the HDS activity but the window size is of more significant importance, which is the key point for the enhanced catalytic performance. [Copyright &y& Elsevier]

Highlights: [•] High quality of the photonic band gap (PBG) films was obtained within 5min. [•] The PBG films were fabricated by the electrophoretic deposition (EPD) process. [•] Quality of the PBG film was affected by the applied voltage strategies. [•] High quality of the PBG films was fabricated by the step-wise decreasing voltage strategy. [Copyright &y& Elsevier]

Abstract: In this work, the composites of LiBH4 and AlF3 were prepared and their hydrogen storage properties were investigated. The AlF3 addition to LiBH4 resulted in significant decreases in dehydrogenation temperature. All the xLiBH4 +AlF3 (x =1, 2, 3, 5) composites started to release hydrogen from about 100°C. The dehydrogenation of the composites was accomplished through several steps, depending on the molar ratio of LiBH4 to AlF3. A new phase Li3AlF6 was formed during the first dehydrogenation step, which further reacted with LiBH4. AlB2 was formed only at temperatures higher than 300°C. Li2B12H12 was detected as an intermediate. The dehydrogenation reactions have significantly reduced and thus favorable enthalpy changes. However, the reversibility of the composites needs to be improved. [Copyright &y& Elsevier]

Abstract: A series of zinc titanate nanoparticles was successfully synthesized using a simple sol–gel technique. The composites were characterized by thermogravimetric and differential thermal analysis (TG-DTA), X-ray diffraction (XRD) patterns, scanning electron microscope (SEM), X-ray photoelectron spectra (XPS) and UV–vis diffuse reflectance spectra (UV–vis). The photocatalytic activity of samples was investigated by degradation of humic acid (HA) in water under xenon lamp. The sample calcined at 800°C was found to exhibit much higher photocatalytic activity than the other samples. The investigation of photocatalytic mechanism indicates that the holes (h+) and ls may be the major reactive species for the degradation of HA. Meanwhile, the processing parameters such as the light source and the dosage of catalysts play an important role in tuning the photocatalytic activity. The enhancement of photocatalytic activity for the zinc titanate nanoparticles calcined at 800°C may be attributed to the higher redox ability, coordination of Ti ions and smaller particle size. [Copyright &y& Elsevier]

Abstract: WO x /ZrO2 catalyzed hydration of cyclohexene in sub-critical water was experimentally investigated. The migration of reaction zone into sub-critical water makes it possible to run the hydration in a single liquid phase, and the reaction is free from the limitation of liquid–liquid phase mass transfer to hydration kinetics. The severe hydrothermal environments favor the transformation of surface active sites on WO x –ZrO2 catalysts to Brønsted acid centers of stronger acidity, which are highly effective for the hydration of cyclohexene to the desired product cyclohexanol. [Copyright &y& Elsevier]

Abstract: From the adsorption point of view, partial hydrogenation of benzene to cyclohexene over the metallic Zn modified Ru-based catalyst was experimentally and theoretically investigated. A decreased hydrogenation activity but increased selectivity to cyclohexene over the prepared Ru-Zn/ZrO2 catalyst was observed in the partial hydrogenation of benzene. Theoretical calculations suggest that the above phenomena are mainly resulted from the depression of the chemisorption of benzene and cyclohexene on the modified catalyst, especially for the latter. Undesired deep hydrogenation from cyclohexene to cyclohexane in the middle and late reaction stage therefore is effectively retarded, by which an improved cyclohexene yield is guaranteed. An optimal Zn content of 2.72wt.% in the Ru-based catalyst was proposed by both the experiment and calculation for the partial hydrogenation of benzene, and a cyclohexene yield up to 44% was obtained over Ru-Zn/ZrO2 catalyst. [Copyright &y& Elsevier]

Abstract: The preparation, characterization and application of a three-layer magnetic nanoparticle composed of an Fe3O4 magnetic core, a Prussian Blue (PB) interlayer and a gold shell (it can be abbreviated as Au–PB–Fe3O4) for an ultrasensitive and reproducible electrochemical immunosensing fabrication were described for the first time in this work. With the employment of the Au–PB–Fe3O4 nanoparticle, a new signal amplification strategy was developed based on bienzyme (horseradish peroxidase and glucose oxidase) functionalized Au–PB–Fe3O4 nanoparticles for an electrochemical immunosensing fabrication by using Carcinoembryonic antigen (CEA) and α-fetoprotein (AFP) as model systems, respectively. The experiment results show that the multilabeled Au–PB–Fe3O4 nanoparticles exhibit satisfying redox electrochemical activity and high enzyme catalysis activity, which predetermine their utility in high sensitivity antibody detection schemes. Furthermore, this immunosensor could be regenerated by simply using an external magnetic field which ensured a reproducible immunosensor with high sensitivity. [Copyright &y& Elsevier]

Abstract: In this work, the hydrogenation of cyclohexene over Ru–Zn/Ru(0001) surface alloy was investigated by a DFT study so as to improve the understanding of the catalytic mechanism of the partial hydrogenation of benzene to cyclohexene over Ru–Zn alloy catalyst. Calculation results show that the presence of Zn atoms on the surface alloy results in not only a direct decrease in sites for the chemisorption of cyclohexene but also a depressed adsorption capability of the neighboring surface Ru sites. For an adsorbed cyclohexene molecule, whether the subsequent hydrogenation can be readily performed actually is determined by the relative position among the Zn atom, the H atom, and the adsorbed cyclohexene molecule. In most cases, the hydrogenation is forbidden because of the repulsion from Zn atoms to the nearby H atoms. Only in the specific situations in which the H atom participating in the reaction is not immediately close to the Zn atom, can the hydrogenation be accomplished with a relatively lower activation energy compared with the reactions on the Ru(0001) surface. From the perspectives of adsorption and reaction kinetics, Ru-based catalyst modified by metallic Zn is no longer suitable for the hydrogenation of cyclohexene, which is supposed to be crucial to the improvement of cyclohexene yield in the partial hydrogenation of benzene over Ru–Zn alloy catalyst. [Copyright &y& Elsevier]

Abstract: With the view of increasing the understanding to the anti-scaling mechanism in the membrane process, zeta potential on the anti-scalant (Calgon and PAA) modified sub-micro calcite surface was measured and was further characterized with a molecular simulation. Experimental results show that the original positively charged calcite in an aqueous solution is reversed to be negatively charged by introducing anti-scalants at a dosage of ppm level. On the basis of theoretical calculation, the observed reversal is resulted from the statistically predominant orientation of negative potential-determining groups in the adsorbed anti-scalant molecules, i.e. Pe:glyph name="dbnd" />O, stretching against the calcite surface. A negative zeta potential prevailing on the calcite surface can effectively prevent the calcite from precipitating on the membrane surface. In the presence of anti-scalants, zeta potential on the sub-micro calcite surface is a sensitive function of calcite content, anti-scalant concentration, salt concentration, and pH of the suspension. [Copyright &y& Elsevier]

The extracellular polymeric substances (EPS) of activated sludge are a mixture of high molecular weight polymers secreted by microorganisms, which are mainly composed of proteins, polysaccharides and humic substances. It is widely accepted that EPS have a good adsorption ability for pollutants with different functional groups. However, recent studies showed the EPS had an inhibitory effect on pollutant sorption, which is contradictory to previous viewpoint. Therefore, in this study, three types of activated sludge with different EPS contents and compositions were used to investigate the role of EPS in an antibiotic-trimethoprim (TMP) sorption process at environmentally relevant concentration. The in situ experiments results showed the adsorption capacity of activated sludge for TMP were increased from 2.98, 5.37 and 28.33 μg/g VSS to 7.87, 12.93 and 150.24 μg/g VSS in nitrifying activated sludge, wastewater treatment plant activated sludge and anaerobic ammonia-oxidized activated sludge, respectively after EPS extracted. The adsorption process can be well described by the pseudo-second-order kinetic model. Results of zeta potential, contact angles and infrared spectrum showed TMP replacing proteins embedded into the cell membrane enhancing the TMP adsorption capacity of activated sludge after EPS extraction. Our results demonstrated that less proteins in EPS of activated sludge is more beneficial for TMP adsorption removal. [Display omitted] • Three different activated sludge were used for TMP sorption experiment. • The adsorption capacity was increased significantly after EPS extraction. • The adsorption process can be described by the pseudo-second-order kinetic model. • The mechanism of TMP adsorption enhancement after EPS extraction was explored. [ABSTRACT FROM AUTHOR]

Abstract: This work describes a two-step conjugate synthesis of a porous organometallic nanostructured materials composed of ferrocenemonocarboxylic (Fc–COOH) and 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA) and then a reagentless amperometric immunosensor prepared with positively charged gold nanoparticles (PGN) immobilized in this nanostructure conductive film is developed. This nanostructured material containing ferrocenyl (PTC–Fc) could easily form stable film on the electrode surface with efficient redox-activity and excellent conductivity. Furthermore, with the negatively charged surface, this film can be used as an interface to adsorbing the PGN, which was prepared in organic solvents at relatively high concentrations with improved monodispersity compared to those prepared in aqueous solution. The presence of PGN provided a congenial microenvironment for adsorbed biomolecules and decreased the electron-transfer impedance. Thus, with carcinoembryonic antibody (anti-CEA) as a model antibody, the proposed immunosensor showed rapid and highly sensitive amperometric response to carcinoembryonic antigen (CEA) with acceptable preparation reproducibility and stability. [Copyright &y& Elsevier]

A ternary photocatalyst of LaOCl/CeO 2 -g-C 3 N 4 was designed and firstly synthesized by a facile KCl–LiCl molten salt method. The 60 %LaOCl/40 %CeO 2 -g-C 3 N 4 with a 6: 4 weight ratio of LaOCl to CeO 2 has an optimal degradation ratio (nearly 100%) for methylene blue (MB) with an impressive cyclic stability. Both of adsorption and photodegradation contribute to the high MB removal ratio, and kinetic study results show that the rate constant of photocatalytic degradation route is 0.0174 min−1, which is less than that of adsorption process (2.4406 min−1). The excellent adsorption performance of 60 %LaOCl/40 %CeO 2 -g-C 3 N 4 is attributed to its negative zeta potential (−35.40 mV) and larger average pore size. The photochemical characterizations suggest that the 60 %LaOCl/40 %CeO 2 -g-C 3 N 4 form a dual Z-scheme heterojunction, which enhances its separation efficiency of photogenerated e - / h + with an outstanding redox ability, and further promotes the photocatalytic activity. [Display omitted] • A ternary photocatalyst of 60 %LaOCl/40 %CeO 2 -g-C 3 N 4 was firstly synthesized by a KCl–LiCl molten salt mothed. • Negative zeta potential and suitable pore structure contribute to the superb adsorption ability of 60 %LaOCl/40 %CeO 2 -g-C 3 N 4. • 60 %LaOCl/40 %CeO 2 -g-C 3 N 4 shows a dual Z-scheme heterojunction which promotes its photocatalytic property. [ABSTRACT FROM AUTHOR]

Abstract A novel sandwich-like immunosensor was efficiently fabricated for detection of carcinoembryonic antigen (CEA) with three dimensional sea-urchin-like PdAuCu nanocrystals (PdAuCu NCs)/ferrocene-grafted-polylysine (Fc-g-PLL) as the label of secondary antibodies (Ab 2) and Au nanoparticles (Au NPs) as the substrate material. Herein, PdAuCu NCs were directly synthesized with polyethylene oxide (PEO) as a growth-directing agent by a facile one-step aqueous method without any organic solvent. Meanwhile, Fc-g-PLL was obtained by covalent linkage of Fc with PLL via Schiff-base reaction. The well-dispersed PdAuCu NCs by Fc-g-PLL have the enlarged surface area, enhanced catalytic properties and superior biocompatibility to amplify the current signals. The resultant immunosensor shows linear relationship of the electrochemical responses with the CEA concentrations within a broader linear range (0.001–100.0 ng mL–1) and a lower detection limit (0.23 pg mL–1, S/N = 3). Furthermore, the immunosensor was explored for practical assay of CEA in human serum samples with accredited results. The novel immunoassay provides a feasible platform for early medical diagnosis. Graphical abstract fx1 Highlights • 3D sea-urchin-like PdAuCu NCs were synthesized by a one-step aqueous method. • Fc-g-PLL was firstly prepared as an electroactive probe. • PdAuCu NCs/Fc-g-PLL acted as an Ab 2 label to amplify the electrochemical signals. • The immunosensor for CEA displayed a broader linear range and a lower detection limit. [ABSTRACT FROM AUTHOR]

Herein, well-defined hollow dendritic AuPtAg alloyed nanocrystals (ANCs) were synthesized by a simple L -proline-mediated one-pot aqueous method. More importantly, the synthesized hollow dendritic architectures provide a suitable platform for immobilization of anti-prostate specific antigen (PSA). The resultant label-free immunosensor exhibited the improved performance for highly sensitive detection of PSA based on the enhanced catalytic currents of K 3 [Fe(CN) 6 ] as a signal probe. Impressively, the immunosensor showed the wide linear range of 0.05–50 ng mL –1 and low detection limit of 0.017 ng mL –1 under optimal conditions for the assay of PSA, couple with the improved stability, reproducibility and selectivity. It provides a promising platform for clinical research and diagnosis. [ABSTRACT FROM AUTHOR]

Continuous visbreaking of heavy oil in a tubular reactor was studied under pressurized steam environments at 10 MPa (MPS) and 18 MPa (HPS). Within the operating range considered, heavy oil and pressurized steam exhibit a liquid-vapor two-phase structure. During the transition from the MPS environment to the HPS environment, the dissolution of water into the oil phase is promoted, thereby reducing the viscosity of the oil phase. According to the lumped reaction kinetics analysis, the reaction behavior of the lumped component VR2 with a boiling point higher than 700 °C determines the visbreaking efficiency in the early visbreaking stage to a large extent. Dealkylation of VR2 and condensation of the lightest lumped component show sensitive responses to improved diffusion in the oil phase. At 400 °C and a space time of 37 min, visbreaking in HPS environment can achieve a viscosity reduction rate of 90%. Meanwhile, the asphaltene content of the product is lower than the feedstock value. • Continuous heavy oil visbreaking was investigated in pressurized steam environments. • Visbreaking products with reduced viscosity and asphaltene content can be obtained. • Dissolution of water in heavy oil reduces the viscosity of the oil phase. • Reaction kinetics of visbreaking respond sensitively to diffusion improvement. • Dealkylation of heaviest components determines initial visbreaking efficiency. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ni 2 P/Al 2 O 3 with small nanoparticles and pure phase was controllably synthesized. • Ni 2 P/Al 2 O 3 shows excellent hydrogenation and desulfurization activities. • Nanoflower-like structure improves dispersion and accessibility of active sites. • The outstanding performance can be attributed to the rich Niδ+ active sites. The hydrogenation of unsaturated bonds and elimination of sulfur impurities in C 9 petroleum resin (C 9 PR) are crucial for improving its quality and performance. In this study, we prepared a nanoflower-like Ni 2 P/Al 2 O 3 catalyst using an in-situ synthesis combined with liquid-phase phosphidation strategy and applied for the production of value-added hydrogenated C 9 PR. In-situ synthesis of Ni-Al hydrotalcite anchors and disperses Ni nanoparticles, while liquid-phase phosphidation introduces high-content Niδ+ and Pδ− active sites and prevents the formation of inactive AlPO 4 , synergistically enhancing both hydrogenation and desulfurization activities. The synthesized Ni 2 P/Al 2 O 3 catalyst achieves a 99.6 % hydrogenation degree and reduces sulfur content from 137 ppm to 0 ppm, much better than the catalysts prepared by conventional impregnation and metal phosphate reduction methods. These results give valuable insights for designing efficient catalysts and advancing single-step hydrorefining processes to generate high-quality, value-added hydrogenated petroleum resins. [ABSTRACT FROM AUTHOR]

Carbon adsorbents have been widely used to remove indoor volatile organic compounds (VOCs), however, the proliferation of bacteria on the carbon adsorbents may deteriorate the indoor air quality and thus pose a serious threat to human health. Herein, we report the synthesis of antibacterial porous carbon spheres (carbonized aminophenol-formaldehyde resin, CAF) with well-dispersed Cu species via an in situ incorporation of Cu2+ during the polymerization of 3-aminophenol-formaldehyde resin followed by a thermal carbonization and reduction process. Compared with CAF, the Cu/CAF- x nanocomposites with Cu loading show a much higher specific surface area (>700 m2 g−1 vs. 569 m2 g−1 for CAF). In addition, the pore size of Cu/CAF- x is ranging from 0.7 to 1.68 nm, which is exactly conducive to adsorb the toluene molecules. As a result, the toluene adsorption capacity is improved from 123.50 mg g−1 for CAF to >170 mg g−1 for Cu/CAF- x. More importantly, such adsorbents possess excellent antibacterial performance, the Cu/CAF-10 (10 wt% of Cu loading) with a concentration of 50 μg mL−1 can completely kill the E. coli within 30 min. Our work paves the way to the development of bifunctional adsorbents with both efficient VOCs adsorption and excellent antibacterial performance. [Display omitted] • An in situ complexation strategy is developed to prepare Cu loaded carbon composite. • Cu/CAF- x show higher toluene adsorption capacity than porous carbon adsorbent. • Cu/CAF-10 with a low concentration of 50 μg mL-1 can kill 100% E. coli within 30 min. • The in situ complexation strategy can be extended to prepare other metal-carbon composites. [ABSTRACT FROM AUTHOR]

With the increasing application of crop straw, the greenhouse gas emissions caused due to crop straw have received increasing attention. However, the current studies have not explored the greenhouse gas emissions from on-farmland consumption of returned straw. Based on a long-term positioning experiment, three treatments were set up in double-cropping rice fields: chemical fertilizer (CF), straw replacing 1/3 nitrogen fertilizer (MS), and straw replacing 2/3 nitrogen fertilizer (HS). We measured the biomass, soil properties, and greenhouse gas emissions of double-cropping rice and then comprehensively evaluated the global warming potential, carbon footprint, and net ecological and economic benefits. The straw treatments (MS and HS) increased the cumulative annual emissions of CH 4 (98.44% and 261.23%), CO 2 (30.85% and 122.29%), and N 2 O (7.37% and 52.50%), the cumulative annual global warming potential (74.15% and 206.12%), average GHG intensity (43.26% and 138.07%), and the annual cumulative net ecosystem carbon budget (52.96% and 100.97%) in the early and late rice growing seasons, respectively. We observed that the real-time greenhouse gas emissions were significantly correlated to the soil microbial functional genes and total carbon, NH 4 +-N, and NO 3 −-N. The results of the random forest model showed that total carbon (13.87%) and nirK abundance (9.80%) were the highest predictors of global warming potential at the booting and maturity stages, respectively during rice growing season. Combining the resource inputs for agricultural production and the greenhouse gas emission potential of the returned straw on its own, MS showed the lowest net greenhouse gas emission, and MS and HS showed significantly increased annual cumulative net ecological economic benefits (38.08% and 34.30%). Overall, MS showed the lowest net greenhouse gas emission and the highest net ecological economic benefits, which is a straw-returning measure with low environmental impact and high economic returns. [Display omitted] • The straw replacing chemical fertilizers increased greenhouse gas emissions. • Straw treatments increased global warming potential and greenhouse gas intensity. • Straw replaced 1/3 nitrogen fertilizer had the lowest net greenhouse gas emissions. • Straw treatments have higher rice yield and agricultural economic benefits. • Straw treatments have higher net ecological economic benefits. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new method allows Al 2 O 3 to simultaneously expose {111} facets with strong acidity and {110} facets with moderate basicity. • MoS 2 and NiS on this Al 2 O 3 works by cooperative action on the newly exposed facets. • The catalyst is used in the thio-etherification of ethanethiol and isoamylene to thioethers. • The combined use of two advanced techniques, crystal facet engineering and cooperative catalysis, is demonstrated. In alumina-based catalysts the properties of the alumina support directly influence the structure (size, morphology, orientation, etc.) of the resulting active phase and ultimately determine the performance of the final catalysts. This paper presents a facile and efficient method for γ-Al 2 O 3 to simultaneously expose {111} facets with strong acidity and {110} facets with moderate basicity. It is shown that the metal oxides NiO x and MoO x can be selectively deposited and subsequently sulfided on the respective facets to form a NiS 2 -MoS 2 /Al 2 O 3 catalyst with substantially enhanced activity for thio-etherification reaction. By cooperative action of the active sites on the newly exposed facets, the catalyst is shown to have superior activity over a conventional NiMoS/Al 2 O 3 catalyst in the thio-etherification reaction between ethanethiol and isoamylene (2-methyl-2-butene) to yield ethylamyl thioethers. Our findings show that tuning the physicochemical properties via crystal facet engineering and inducing cooperative catalysis via preferential deposition of active metals open a novel avenue for the rational design and synthesis of high performance catalysts. [ABSTRACT FROM AUTHOR]

Abstract: The binary Cu–Zr system is an important material for various implementations. The copper–zirconium alloy is one of the best known transition metal–metal binary system which may be obtained in a glassy state by conventional melt-spinning technique over a wide range of composition. On other hand, substitution of Zr for Al in the CuZnAl oxide system was found to improve the catalytic performance during oxidative steam reforming of methanol. In these cases the knowledge of phase equilibria and thermodynamic properties of the binary Cu–Zr system seems to be important for an industry. A new thermodynamic description of this system was proposed based on Calphad method. A good agreement between experimental information and calculation was found. [Copyright &y& Elsevier]

• Detailed characterization of ionic liquid drops impacting on heated porous surfaces. • Increased temperature and velocity accelerate the droplet penetration. • Ionic liquid drop exhibits smaller diameter, height, and more stability than water. • Evaporation alters the relationship between residual volume and contact time. The impingement dynamics of a promising ionic liquid absorbent, namely, 1-ethyl-3-methylimidazolium acetate ([EMIm]Ac) in droplet falling film flow modes on heated porous surfaces in absorption refrigeration were investigated experimentally. The influences of impact velocity and surface temperature on the ionic liquid droplet spreading diameter, dynamic contact angle, spreading height, and residual volume against the heated porous surfaces were explored. The results indicated that the residual volume generally decreased in linear with increasing contact time at 323.15 K, while the dependence exhibited a polynomial behavior at higher heating temperatures. Compared to the impingement behaviors of deionized water droplets, such as oscillations and capillary waves were not observed in [EMIm]Ac droplets. The residual volume of the deionized water droplets varied exponentially with the contact time owing to the combined effects of the evaporation, penetration, and variation of the thermophysical properties of the droplet. Moreover, increases in the impact velocity and surface temperature enlarge the spreading diameter and accelerate the droplet penetration for the ionic liquid. [ABSTRACT FROM AUTHOR]

The effect of the timing of adding 1 wt% decalin as a hydrogen donor on heavy oil visbreaking was studied. Experiments show that either premixing decalin with heavy oil or adding decalin during the reaction accelerates the formation of light distillates and improves the efficiency of viscosity reduction. Premixing with heavy oil is an appropriate way to add decalin. After 10 min of reaction at 400 ℃, the viscosity reduction rate of the product reaches 90% and the asphaltene content of the product is 1.8 wt% lower than that of the raw heavy oil. According to theoretical calculations, the active hydrogens of decalin preferentially saturate the aromatic C radicals that are critical for condensation. The equilibrium constant of the H-donation reaches the order of 105, while the activation energy of the reaction is only about 26 kJ/mol. The thermal cracking of decalin itself releases active and small-sized radicals, which accelerate visbreaking by participating in the dealkylation network of heavy oil molecules. • Decalin cracking releases radicals with high activity and diffusivity. • Addition of decalin in visbreaking greatly accelerates viscosity reduction. • Decalin selectively saturates aromatic C radicals vital for condensation. • Premixing decalin with heavy oil inhibits condensation in early reaction stage. • Premixing decalin as a hydrogen donor with heavy oil in visbreaking is recommended. [ABSTRACT FROM AUTHOR]

Nowadays, synthesis of novel organic photosensitizer is imperative but challenging for photoelectrochemical (PEC) assay in analytical and biomedical fields. In this work, the PEC responses enhanced about 4.3 folds after in situ electrostatic assembly of 1-butyl-3-methylimidazole tetrafluoroborate ([BIm][BF 4 ]) on meso-tetra (4-carboxyphenyl) porphine (TP), which was first covalently linked with NH 2 modified indium tin oxide electrode ([BIm]+-–TP-NH 2 -ITO). Moreover, the [BIm]+-–TP-NH 2 -ITO showed a much larger photocurrent in a water/dimethyl sulfoxide (DMSO) binary solvent with a water fraction (f w) of 90%, which displayed 6.7-fold increase over that in pure DMSO, coupled by discussing the PEC enhanced mechanism in detail. Then, the PEC signals were sharply quenched via a competitive reaction between magnetic bead linked dsDNA (i.e., initial hybridization of aptamer DNA with linking DNA) and HCT-116 cells (closely associated with CRC), where the liberated L-DNA stripped the [BIm]+ from [BIm]+-–TP-NH 2 -ITO. The PEC detection strategy exhibited a wider linear range (30 ∼ 3 × 105 cells mL–1) and a lower limit of detection (6 cells mL–1), achieving single-cell bioanalysis even in diluted human serum sample. The in situ assembly strategy offers a valuable biosensing platform to amplify the PEC signals with advanced organic photosensitizer for early diagnosis of tumors. [ABSTRACT FROM AUTHOR]

• A US-responsive CO release system was constructed for the first time. • The Fenton-like effect of VS 4 was reported for the first time. • The GSH-depleting effect of Mn(CO) 5 Br was first discovered. • CaCO 3 shell layer can achieve tumor microenvironment responsive drug release and lead to Ca2+ overload. • Generation of multiple mitochondrial apoptosis-based therapeutic molecules such as ROS, CO, and Ca2+. Mitochondria, the energy suppliers of cells, are crucial for cell survival and proliferation. Tumor therapy based on mitochondrial apoptosis holds good promise. Currently utilized strategies, such as the production of CO and ROS and Ca2+ overload, are not highly selective and have limited effectiveness. In this study, a smart nanoplatform (V-Mn@Ca) controlled by ultrasound (US) and with high therapeutic efficacy was designed, which can specifically target the tumor site and activate mitochondrial apoptosis at multiple levels. Specifically, VS 4 , featuring a narrow band gap, are utilized to generate a Fenton-like effect. Loading Mn(CO) 5 Br enables a US-induced release of CO and depletion of GSH, which would further enhance ROS-mediated mitochondrial apoptosis. Finally, an encapsulated CaCO 3 shell layer disrupts Ca2+ homeostasis in tumor cells. Overall, our study shows that the V-Mn@Ca platform triggers CO, ROS, and Ca2+ production in a controlled manner. Thus, providing sonodynamic therapy and CO therapy on a timed-targeted basis for enhanced mitochondrial apoptosis and subsequent tumor cell death, which inhibits tumor growth. [ABSTRACT FROM AUTHOR]

Graphical abstract By the differences in heavy oil composition and thermodynamic state of water applied, the oil-in-water emulsion structure of heavy oil/SCW systems may transit to the condensed emulsion or pseudo single-phase structure, determining their feasible application in upgrading of heavy oil. Highlights • MD simulation on dissolution of PAHs or PAH mixtures in sub-CW/SCW was applied. • Dissolution of heavy PAHs in sub-CW/SCW is sensitive to thermodynamic state of water. • Preferential dissolution of light PAHs occurs during dissolution of PAH mixtures. • Electrostatic interaction promotes the dissolution of PAHs in sub-CW/SCW. • Heavy oil/SCW could exist in condensed emulsion or pseudo single-phase structure. Abstract To get a better understanding of the upgrading of heavy oil under severe hydrothermal environment, a molecular dynamics simulation on the dissolution of oil droplets containing polycyclic aromatic hydrocarbons (PAHs) or PAH mixtures in subcritical or supercritical water (sub-CW/SCW) was applied. Being the representative of light PAHs, naphthalene dissolves readily into sub-CW/SCW. The dissolution of heavy PAHs, like benzo[α]pyrene and benzo[ghi]perylene however is sensitive to the thermodynamic state of water. During the dissolution of PAH mixtures, a preferential dissolution of light PAHs into the water phase occurs, leaving heavy PAHs concentrated in the oil droplets. With the simultaneous increase in water density and temperature, the miscibility of PAHs with sub-CW/SCW is improved by the enhanced attractive electrostatic interaction between PAHs and hydrothermal environment and the weakened interaction between PAHs. By the differences in heavy oil composition and the thermodynamic state of water, the upgrading of heavy oil in sub-CW/SCW could be run in the condensed emulsion or pseudo single-phase structure. [ABSTRACT FROM AUTHOR]

[Display omitted] • A series of Pd/SiO 2 catalysts with graded pore sizes were successfully prepared. • Macroporous catalysts facilitate NBR diffusion and improve metal utilization. • The correlation between D cat /D NBR with HD and Weisz modulus Φ were revealed. • Pd/N-SiO 2 -70 shows excellent activity (96.7%) and selectivity (100 %) to C = C. Pore diffusion effect plays a crucial role in heterogeneous hydrogenation of unsaturated polymers. However, how large pore size can eliminate the pore diffusion limitation remains a controversial issue. Herein, we prepared a series of Pd/SiO 2 catalysts with graded pore sizes and investigated the effect of pore size on hydrogenation activity of nitrile butadiene rubber (NBR). It is found that when the catalyst pore size (D cat) is 7 times of the diameter of NBR chains (D NBR), the Weisz modulus Φ can be reduced to < 0.3 thus the internal mass transfer limitation can be eliminated, making NBR easier to approach the active sites. Consequently, the catalysts with the D cat /D NBR > 7 exhibit excellent catalytic activity (96.7%) and selectivity (100%) to C = C. This work emphasizes that the pore size of catalysts can regulate the pore transfer limitation and the accessibility of internal active sites, providing useful guidance for the design of efficient macromolecular hydrogenation catalysts. [ABSTRACT FROM AUTHOR]

Supported Pd catalyst with an enhanced catalytic performance for polystyrene hydrogenation was successfully prepared by using macroporous silica microspheres (MSM) as the support. In order to eliminate the macromolecular diffusion limitation and improve the metal utilization, MSM was treated with steam at 800 °C first to remove mesopores and then refluxed with aqueous solutions to increase Si OH groups on the surface for Pd immobilization. The optimum support was obtained after the steam treatment for 2 h and using ammonia solution as reflux liquors, and the corresponding catalyst showed superior hydrogenation activity with a high conversion of 95%. [ABSTRACT FROM AUTHOR]

Herein, bimetallic core-shell Au@Pt nanocrystals (Au@Pt NCs) were prepared by a simple one-pot aqueous method using 2-pyrrolidone-5-carboxylic acid sodium salt (PCA-Na) as a new and green growth-directing agent. The obtained architectures displayed excellent catalytic activity towards oxygen reduction reaction (ORR) compared with commercial Pt/C catalyst. A novel immunosensor was constructed via assembly prostate specific antibody on the surface of Au@Pt NCs. It was found that the ORR currents were significantly suppressed due to the specific antigen-antibody reaction. The ultra-sensitive determination of prostate specific antigen (PSA) was realized on account of the immunocomplex impeding the redox probe accessible to the electrode. The immunosensor exhibited good analytical performance for the assay of PSA with the wide linear range of 0.1 ~ 50 ng mL –1 and low detection limit of 0.018 ng mL –1 ( S / N = 3), coupled with the improved stability, reproducibility and selectivity. [ABSTRACT FROM AUTHOR]

The strategy of adding tetralin as a H-donor in the thermal processing of heavy oil was investigated by experimental characterization and theoretical calculations. According to the experiments, the timing of adding 1 wt% of tetralin has a great influence on the visbreaking performance of heavy oil. Calculations based on density functional theory showed that benzyl radicals released from the thermal cracking of tetralin accelerate the dealkylation that determines the heavy oil upgrading. Meanwhile, H α provided by tetralin is able to selectively saturate aromatic C radicals which are essential for condensation. Compared with the conventional H-donor addition, i.e., pre-mixing of tetralin with heavy oil, a similar viscosity reduction rate of about 98% can be obtained during the visbreaking with delayed tetralin addition. Furthermore, the addition of tetralin before the significant occurrence of condensation further increases the conversion of vacuum residue fraction by 3.4% and reduces the asphaltene content of the product by 2.6 wt%. [Display omitted] • Tetralin cracking releases benzyl radicals which accelerate heavy oil upgrading. • H α provided by tetralin selectively saturates aromatic C radicals. • Pre-mixing of tetralin with heavy oil affects sufficient condensation inhibition. • In visbreaking tetralin should be added before apparent occurrence of condensation. • In delayed coking the addition of tetralin is not recommended. [ABSTRACT FROM AUTHOR]

In this work, we consider the fluid/gravity correspondence for general rotating black holes. By using the suitable boundary condition in near horizon limit, we study the correspondence between gravitational perturbation and fluid equation. We find that the dual fluid equation for rotating black holes contains a Coriolis force term, which is closely related to the angular velocity of the black hole horizon. This can be seen as a dual effect for the frame-dragging effect of rotating black hole under the holographic picture. [ABSTRACT FROM AUTHOR]

[Display omitted] • The flower-like nickel phosphide catalysts were prepared by a hydrotalcite strategy. • Ni 2 P/Al 2 O 3 catalyst showed excellent catalytic activity and desulfurization ability. • The outstanding performance ascribed to the rich active Niδ+ species. • The enhanced stability was due to strong interaction between active sites and support. The catalytic hydrogenation of petroleum resin (PR) to high value-added hydrogenated PR (HPR) represents a forward-looking technology for upgrading the pyrolysis petroleum by-product. Herein, flower-like and pure-phase supported nickel phosphide catalysts were controllably fabricated through a hydrotalcite strategy with red phosphorous as the P source. The PR hydrogenation activity of the catalysts followed the order of Ni 2 P/Al 2 O 3 > NiP 2 /Al 2 O 3 > Ni/Al 2 O 3 > imp-Ni 2 P/Al 2 O 3 catalysts (prepared by the impregnation method). Such enhanced performance of Ni 2 P/Al 2 O 3 could be ascribed to small nickel phosphide particle size and rich active Niδ+ species. Notably, the sulfur contents of PR were effectively reduced from 55.4 (C 5 PR) and 72.3 ppm (C 9 PR) to 3.8 and 7.9 ppm after hydrogenation by Ni 2 P/Al 2 O 3. Meanwhile, Ni 2 P/Al 2 O 3 also exhibited good stability with the hydrogenation degree of HC 5 PR maintaining at 94.39 % after 100 h. Our work provides a promising nickel phosphide catalyst with outstanding hydrogenation activity, hydrodesulfurization ability, and stability toward PR hydrogenation. [ABSTRACT FROM AUTHOR]

The impact dynamics of water drops on porous surfaces wetted by a hygroscopic ionic liquid aqueous solution are investigated. Firstly, to better illustrate the different dynamic characteristics of water drops on ionic liquid-wetted porous surfaces, it is compared with that on the dry and water-wetted porous surfaces. The results indicate that, the water drop barely penetrates on the dry porous surface at ambient temperature, but penetrate when the surface temperature is raised or the surface is pre-wetted. The maximum spreading and penetration of the droplet on the ionic liquid-wetted surface is larger and faster than that on the water-wetted surface. Then, the effect of the mass fraction of aqueous ionic liquid, impact velocity, porosity on the spreading and penetration is explored. The larger the mass fraction of aqueous ionic liquid on the porous surface, the faster the droplet spreading factor, height, and residual volume decrease. The effect of impact velocity is even more pronounced for the water droplets impacting on pure ionic liquid-wetted porous surfaces. A higher porosity contributes to a smaller spreading diameter but a larger volume decreasing rate on the wetted porous surface. [ABSTRACT FROM AUTHOR]

The performance of introducing a free radical initiator into dealkylation-based visbreaking of heavy oil in the N 2 or supercritical benzene (SC benzene) medium was investigated. Calculations based on density functional theory show that the introduction of di-tert-butyl peroxide (DTBP) into heavy oil visbreaking results in the formation of alkyl C radicals similar to those naturally formed in high temperature initiation. The visbreaking in SC benzene environment is sensitive to the introduction of DTBP, which is different from the visbreaking in N 2 environment. According to reaction kinetics analysis, the presence of SC benzene solvent and the introduction of DTBP greatly accelerate the dealkylation related lumped reactions. Benefiting from improved diffusion environment, the superimposed radicals resulting from DTBP introduction effectively participate in visbreaking and selectively accelerate dealkylation. After only 10–20 min of reaction at 380 °C, visbreaking products with satisfactory viscosity reduction, reduced asphaltene content and improved light component yield can be obtained. • Initiator-introduced heavy oil visbreaking in supercritical benzene was examined. • DTBP introduction results in rapid superposition of alkyl C radicals. • The presence of supercritical benzene accelerates visbreaking. • Superimposed radicals effectively participate in visbreaking in SC benzene. • Best upgrading is obtained in DTBP-introduced visbreaking in SC benzene. [ABSTRACT FROM AUTHOR]

To improve the understanding of the condensation of asphaltenes in supercritical water (SCW), the solvation of asphaltenes under SCW environments was investigated with molecular dynamics simulation. The simulation results indicate that the repulsive van der Waals interaction has a primary influence on the nature and the magnitude of the interaction between asphaltenes and SCW. A cavity short-range solvent structure surrounding asphaltenes thus is formed, and the solvation free energy ( G sol ) of asphaltenes in SCW has a positive sign in most cases. The scale of cavities and the value of G sol both are determined mainly by the bulk density of water. By the repulsive asphaltenes/SCW interaction and the attractive π–π aromatic interaction, the aggregation of asphaltenes in SCW occurs spontaneously. The asphaltene clusters formed, containing asphaltene monomers and nanoaggregates, present a coke-like supramolecular structure. Benefiting from excellent diffusivity in SCW, the aggregation of asphaltenes in SCW can be accomplished rapidly. [ABSTRACT FROM AUTHOR]

A multi-scale approach has been formulated in a previous work. The influence of HVAC system in supermarket on the performance of vertical open refrigerated display cabinet (VORDC) is considered. The influence is evaluated by varying the supply air temperature and velocity at the diffusers of HVAC. The computational results show that there is a direct interaction between the HVAC system and VORDC in supermarket. When the supply air temperature of HVAC system decreases from 19 °C to 16 °C, the electricity energy input in VORDC system decreases by 6.36%, and the highest products temperature is reduced by 0.18 °C. When the diffuser supply air velocity of HVAC system increases from 2.0 m/s to 3.5 m/s, the energy input in VORDC system decreases by 23.4%, and the highest product temperature reduces by 0.4 °C. [ABSTRACT FROM AUTHOR]

A multi-scale approach is presented to investigate the characteristics of fluid flow and heat transfer of vertical open refrigerated display cabinet (VORDC) coupled with heating, ventilation and air conditioning (HVAC) system in supermarket. It includes three different scale models: supermarket-scale, cabinet-scale and shelf-scale. The results of temperature, velocity and relative humidity from these three length scale models are compared, and demonstrate that the deviations of temperature and relative humidity at return air grille are 13.46% and 0.20% with the supermarket-scale and cabinet-scale models, respectively. The average deviations of temperature and velocity for the second shelf are 1.3 °C and 0.084 m s −1 among the three scale models, respectively. The temperature and velocity fields are both in a good agreement. It means that this multi-scale method can predict the temperature and velocity distribution from the supermarket-scale to the shelf-scale correctly. [ABSTRACT FROM AUTHOR]

MicroRNA 122 (miR-122) is a tumor suppressor for hepatocellular carcinoma (HCC) but is lowly expressed in HCC cells. MiR-151 is aberrantly overexpressed in HCC cells and promotes HCC metastasis yet its roles on HCC tumorigenicity are unknown. To combat HCC tumorigenicity/metastasis, we developed Sleeping Beauty (SB)-based hybrid baculovirus (BV) vectors that expressed (i) miR-122 precursors (pre-miR-122), (ii) miR-151 sponges, or (iii) pre-miR-122 and miR-151 sponges. Transduction of aggressive HCC cells (Mahlavu) with the pre-miR-122-expressing BV tremendously enhanced miR-122 levels for >6 weeks, suppressed the levels of downstream effectors (e.g., ADAM10 and Bcl-w), proliferation, anchorage-independent growth, motility and migration/invasion in vitro. Intratumoral injection of the pre-miR-122-expressing BV attenuated the HCC growth/metastasis. The miR-151 sponges-expressing BV diminished the miR-151 levels for 6 weeks, enhanced RhoGDIA expression, suppressed RhoGTPases, as well as motility and migration/invasion of Mahlavu cells. Intratumoral injection of the miR-151 sponge-expressing BV impeded not only HCC metastasis but also cell proliferation, MMP expression and tumor growth in vivo. The BV co-expressing pre-miR-122 and miR-151 sponges also simultaneously enhanced miR-122 expression and inhibited miR-151, and conferred antitumor/anti-metastasis effects albeit lack of synergism. These data implicate the potentials of the SB-based hybrid BV for persistently modulating miRNA and suppressing HCC tumorigenicity/metastasis. [ABSTRACT FROM AUTHOR]

DNA methyltransferase, a key enzyme mediating DNA methylation, is involved in numerous processes including genomic imprinting, X chromosome inactivation, transposable element suppression, and immune defense in vertebrates. In the present study, a DNA cytosine-5-methyltransferase 3 was identified from oyster Crassostrea gigas (designed as Cg DNMT3). There were a PWWP domain, a PHD domain and a DNA-methylase domain in the deduced amino acid sequences of Cg DNMT3, and the conserved motifs I, IV, VI, Ⅷ, IX and X were identified in its C-terminal catalytic DNA-methylase domain. The mRNA transcripts of Cg DNMT3 were detected in haemocytes, mantle, gill, adductor muscle, digestive gland and labial palp, with higher expression level in haemocytes (6.54 folds of those in gill, p < 0.01). The expression level of Cg DNMT3 mRNA in haemocytes increased significantly after LPS primed (2.87 folds of that in control group, p < 0.05) in vitro or Vibrio splendidus challenging (1.94 folds of that in control group, p < 0.05) in vivo. Immunocytochemical analysis revealed that Cg DNMT3 protein was distributed mainly in cytoplasm and partial in nucleus of oyster haemocytes. After Cg DNMT3 was transfected and expressed in HEK293T cells, the DNA 5-methylcytosine (5-mc) level in the transfected group was significantly increased, which was 1.22 folds (p < 0.05) of the pcDNA-3.1 group. The expressions of oyster Cg IL17-1, Cg IL17-2 and Cg IL17-5 in haemocytes increased (13.05 folds, 4.78 folds and 9.41 folds of that in control group, respectively) at 12 h after V. splendidus challenging, but the increase were significantly inhibited when the oysters were pre-treated with DNA methyltransferase inhibitor 5-Azacytidine, which were 9 folds, 1.93 folds and 3.22 folds of that in control group, respectively. These results collectively suggested that Cg DNMT3 was a conserved member of DNA methyltransferase 3 family in oyster, and participated in regulating the expression of cytokines during immune response. • Cg DNMT3 is a conserved member of DNMT3 family in oysters. • Cg DNMT3 is constitutively expressed in adult tissues with slightly higher level in haemocyets. • LPS stimulation and Vibrio splendidus challenge up-regulated the expression of Cg DNMT3. • Cg DNMT3 was involved in the regulation of Cg IL17 expressions during immune response. [ABSTRACT FROM AUTHOR]

• Visbreaking of heavy oil with high metal and asphaltene content was investigated. • Coupling of porphyrin metals with asphaltenes promotes asphaltene aggregation. • Asphaltene condensation is accelerated by high content and aggregation. • Asphaltenes with highest metal content participate in condensation to coke first. The visbreaking of Canadian oil sands bitumen (OSB) and Tahe atmospheric residue (AR) with high metal and asphaltene content was studied to deepen the understanding of the utilization of ultra-inferior heavy oil. The total content of nickel and vanadium in the asphaltenes contained in Canadian OSB reaches 1300 ppm, promoting large-scale aggregation of asphaltenes. Driven by high asphaltene content of 19.3 wt% and large-scale aggregation of asphaltenes, Canadian OSB with an initial boiling point (IBP) of 500 °C exhibits rapid condensation during visbreaking. Furthermore, those asphaltenes with the highest metal content participate in condensation first, producing metallic nickel in the formed coke. By changing cutting strategy, the group composition and metal distribution of Canadian OSB can be adjusted. A viscosity reduction rate above 99 % is obtained during the visbreaking of Canadian OSB with an IBP of 350 °C, similar to the visbreaking of Tahe AR with an asphaltene content of 15.4 wt% and a total metal content of 300 ppm. [ABSTRACT FROM AUTHOR]

• Reaction kinetics analysis of heavy oil visbreaking in SC benzene was applied. • SCF visbreaking features low reaction temperature and shortened reaction time. • Competition between dealkylation and condensation exists throughout visbreaking. • Dealkylation-based visbreaking is accelerated by reducing diffusion limitation. • Condensation-based lumped reactions respond sensitively to temperature variation. To understand the reaction behavior of heavy oil visbreaking with reduced diffusion limitation, the visbreaking of an atmospheric residual oil in the solvent of supercritical benzene (SC benzene) was applied, followed by a reaction kinetics analysis based on a hybrid lumping with combination of boiling point distribution and group composition of oil components. The visbreaking under SC benzene environment was found to be much faster than that under nitrogen environment, proceeding effectively even at a temperature lower to 350 °C. Although the dealkylation-based lumped reactions responsible for light component production and viscosity reduction are supposed to dominate the visbreaking, a competition between dealkylation and condensation exists throughout the visbreaking. Because of the reduced diffusion limitation to reaction kinetics, the condensation-based lumped reactions with a higher activation energy up to 306 kJ.mol−1 respond more sensitively to the variation of reaction temperature, greatly shortening the reaction time window for the visbreaking at high temperatures. [ABSTRACT FROM AUTHOR]