Phase behavior of colloidal nanoparticles and their enhancement effect on the rheological properties of polymer solutions and gels.

The interaction between nanoparticles and polymers has been of great interest in colloidal theory and novel materials. For example, the properties of polyacrylamide solutions and gels, which are usually used for conformance control and water shut-off in oilfields, can be improved with the addition of nanoparticles. This underlying mechanism and its applicability are investigated in this paper.

Investigation on the interlayer coupling and bonding in layered nitride-halides ThNF and ThNCl.

Motivated by recent experimental observation [N. Z. Wang, , Inorg.

Synergistic advanced oxidation process for enhanced degradation of organic pollutants in spent sulfuric acid over recoverable apricot shell-derived biochar catalyst.

The sulfuric acid-based alkylation process, which leads the industrial application market, still struggles with effectively removing a large number of organic pollutants from hazardous spent sulfuric acid. A synergistic advanced oxidation process was constructed to degrade the organic pollutants with HO and sodium persulfate as the synergistic oxidants and apricot shell-derived biochar (OBC) as the catalyst. Taking the total organic carbon (TOC) and the color scale as the indices, the effects of critical experimental factors, , reaction temperature, initial oxidant concentration, catalyst dosage, and aeration rate, were optimized.

Formation and Distribution of Different Pore Types in the Lacustrine Calcareous Shale: Insights from XRD, FE-SEM, and Low-Pressure Nitrogen Adsorption Analyses.

Pore types and pore structure parameters are the important factors affecting the storage capacity of a shale oil reservoir. Pore morphology and mineralogical composition of shales have diverse effects on the upgrading of various phases of shale oil. To interpret the formation and distribution of different pore types and their structure parameters in the lacustrine calcareous shale, a combination of polarizing microscopy, X-ray diffraction, total organic carbon (TOC), field-emission scanning electron microscopy, and low-pressure nitrogen adsorption experiments were conducted on the Es3x shale of the Eocene Shahejie Formation in the Zhanhua Depression.

Rational Design and Effective Control of Gold-Based Bimetallic Electrocatalyst for Boosting CO Reduction Reaction: A First-Principles Study.

Electrochemical CO reduction reaction (CO RR) is an effective strategy converting CO to value-added products. Au is regarded as an efficient catalyst for electrochemical reduction of CO to CO, and the introduction of Pd can tune CO RR properties due to its strong affinity to CO. Herein, Au-Pd bimetallic electrocatalysts with different metal ratio were firstly investigated on CO RR mechanism by using density functional theory.

Dynamical behavior of a higher order stochastically perturbed SIRI epidemic model with relapse and media coverage.

This paper is intended to explore a higher order stochastically perturbed SIRI epidemic model with relapse and media coverage. Firstly, we derive sufficient criteria for the existence and uniqueness of an ergodic stationary distribution of positive solutions to the system by establishing a suitable stochastic Lyapunov function. Then we obtain adequate conditions for complete eradication and wiping out of the infectious disease.

High-performance aqueous sodium-ion battery using a hybrid electrolyte with a wide electrochemical stability window.

The practical application of aqueous sodium-ion batteries (ASIBs) is limited by the electrolysis of water, which results in a low working voltage and energy density of ASIBs. Here, a NaClO-based acetonitrile/water hybrid electrolyte (NaClO(HO)AN) is applied to ASIBs for the first time, which effectively extends the electrochemical stability window (ESW) to 3.0 V and reduces the internal resistance of the battery.

Giant surfactant-stabilized N-foam for enhanced oil recovery after water flooding.

A novel giant surfactant, APOSS-PS, possessing good surface activity, and viscosifying and reinforcing ability as a foam stabilizer, was synthesized successfully to enhance the physical properties of foaming solutions and foam. APOSS-PS was widely distributed at the foam gas-liquid interface and adjacent liquid layers through diffusion and adsorption, obviously decreasing the surface tension and improving the foamability and stability of the foam. Furthermore, the aggregation of APOSS-PS in the foam films resulted in the formation of a self-assembled nano-sized network through supramolecular interactions (such as hydrogen bonding, π-π stacking, and van der Waals attraction), thus increasing the foam viscoelasticity, including its interfacial viscoelastic modulus and apparent viscosity.

The behaviour of water on the surface of kaolinite with an oscillating electric field.

A quantitative understanding of oscillating electric field effects on the behaviour of water on the surface of kaolinite is vital for research in the field of clay-water systems. The behaviour of water molecules on the (0 0 1) and (0 0 -1) surfaces of kaolinite are systematically investigated in the absence or presence of an oscillating electric field using molecular dynamics simulations. The simulated results demonstrate that the applied oscillating electric fields parallel to kaolinite surface contribute to decreased amounts of adsorbed water molecules on the (0 0 1) surface of kaolinite.

Fungal community analysis in seawater of the Mariana Trench as estimated by Illumina HiSeq.

This study assessed the diversity and distribution of fungal communities in thirteen marine seawater samples from four sites (L1, L3, L4 and L7) of the Mariana Trench, with a depth range of 1000-4000 meters, using Illumine Hiseq sequencing with fungal-specific primers targeting the internal transcribed spacer (ITS) region of the ribosomal rRNA gene. Sedimentary fungal communities showed high diversity with 209 880 reads belonging to 91 operational taxonomic units (OTUs). Of these OTUs, 45 belonged to the Ascomycota, 37 to Basidiomycota, 3 to Chytridiomycota, 1 to Glomeromycota, 1 to Cryptomycota, and 4 to unknown fungi.

Preparation and characterization of petroleum-based mesophase pitch by thermal condensation with in-process hydrogenation.

A petroleum aromatic-rich component was used to prepare mesophase pitch by thermal condensation. In-process hydrogenation method was employed to achieve the hydrogenation reaction of intermediates generated during the thermal reaction using tetrahydronaphthalene (THN) as a hydrogen donor. Impacts of in-process hydrogenation on the properties of intermediates and mesophase pitches were investigated.

Laboratory evaluation and numerical simulation of the alkali-surfactant-polymer synergistic mechanism in chemical flooding.

Alkali-surfactant-polymer (ASP) flooding, which can reduce interfacial tension (IFT) and the mobility ratio between oil and water phases, has been proven to be effective for enhancing oil recovery in laboratory experiments and field pilots. However, the study of interactions within alkali-surfactant-polymers for chemical flooding is neither comprehensive nor complete until now. Laboratory experiments were conducted and a corresponding numerical simulation model was established to characterize multiple component interactions during the ASP flooding process.

Polydopamine-coated graphene nanosheets as efficient electrocatalysts for oxygen reduction reaction.

Polydopamine-modified graphene (G-PDA) materials were synthesized by polymerization of a dopamine monomer on the surface of graphene oxide. X-ray photoelectron spectroscopy (XPS) has confirmed that new N-containing functional groups are formed during the synthesis process, which result in the excellent electrocatalytic activity of the composite towards ORR in terms of onset potential, number of electron transferred and limiting current density. The electrocatalytic activity of the optimized G-PDA sample is better than N-doped graphene and comparable to the commercial 20 wt% Pt/C catalyst.

Hydroalkylation modification of naphthene-based aromatic-rich fraction and its influences on mesophase development.

Naphthene-based aromatic-rich fraction was modified by tetrahydronaphthalene and polyethylene glycol to obtain modified materials which were selected to prepare mesophase pitches by a direct condensation method. The structural composition of modified materials were characterized by simulated distillation (SIMDIS), elemental analysis, Fourier transform infrared spectrometry (FTIR) and H nuclear magnetic resonance (H NMR) spectroscopy. Influences of the naphthenic structures and alkyl chains in modified materials on the formation and development of mesophase structures were investigated by analyzing variations in optical texture, softening point, carbon residue, molecular and microcrystal structure of mesophase pitch.

Pressure-driven supercritical CO transport through a silica nanochannel.

A thorough understanding of supercritical CO (scCO) transport through nanochannels is of prime significance for the effective exploitation of shale resources and the mitigation of greenhouse gas emission. In this work, we employed the non-equilibrium molecular dynamics simulations method to investigate the pressure-driven scCO transport behavior through silica nanochannels with different external forces and pore sizes. The simulations reveal that the capability of scCO diffusion enhances both in the bulk region and the surface adsorbed layer with the increasing of pressure gradient or nanochannel size, in addition, the slip length increases nonlinearly with the external acceleration or nanochannel width increases and finally reaches a maximum value.

Controllable Photodynamic Therapy Implemented by Regulating Singlet Oxygen Efficiency.

With singlet oxygen (O) as the active agent, photodynamic therapy (PDT) is a promising technique for the treatment of various tumors and cancers. But it is hampered by the poor selectivity of most traditional photosensitizers (PS). In this review, we present a summary of controllable PDT implemented by regulating singlet oxygen efficiency.

Initial hydrogenations of pyridine on MoP(001): a density functional study.

The initial hydrogenations of pyridine on MoP(001) with various hydrogen species are studied using self-consistent periodic density functional theory (DFT). The possible surface hydrogen species are examined by studying interaction of H(2) and H(2)S with the surface, and the results suggest that the rational hydrogen source for pyridine hydrogenations should be surface hydrogen atoms, followed by adsorbed H(2)S and SH. On MoP(001), pyridine has two types of adsorption modes, i.

Theoretical investigation of the reaction of Mn+ with ethylene oxide.

The potential energy surfaces of Mn(+) reaction with ethylene oxide in both the septet and quintet states are investigated at the B3LYP/DZVP level of theory. The reaction paths leading to the products of MnO(+), MnO, MnCH(2)(+), MnCH(3), and MnH(+) are described in detail. Two types of encounter complexes of Mn(+) with ethylene oxide are formed because of attachments of the metal at different sites of ethylene oxide, i.