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solvents, etc ; aerosols; air pollution; air quality; alkenes; aromatic compounds; combustion; pollution control; urban areas; volatile organic compounds; China; Show all 11 Subjects
Abstract:
... Understanding the emission sources of volatile organic compounds (VOCs) is critical for air pollution mitigation. Continuous measurements of atmospheric VOCs were conducted from January to February in Hangzhou in 2021. The average measured concentration of total VOCs (TVOCs) was 38.2 ± 20.9 ppb, > 42% lower than that reported by previous studies at the urban center in Hangzhou. The VOC concentrati ...
... End group engineering on the side chain of π-conjugated donor polymers is explored as an effective way to develop efficient photovoltaic devices. In this work, we designed and synthesized three new π-conjugated polymers (PBDT-BZ-1, PBDT-S-BZ, and PBDT-BZ-F) with terminal aryl end groups on the side chain of chlorine-substituted benzo[1,2-b:4,5b′]dithiophene (BDT). End group modifications showed no ...
... An AIE-active pyran derivative bearing bromine, but no alkyl chains or amide units was found to be able to gelate organic solvent aided by the halogen-assisted balanced intermolecular π-π interactions. Moreover, the pyran derivative exhibits tri-colored high-contrast mechanochromism based on the transition between monomer and different π dimers. ...
solvents, etc ; acetylene; air; air pollution control; alkenes; aromatic compounds; cities; evaporation; inventories; models; natural gas; oil and gas industry; ozone; China; Show all 14 Subjects
Abstract:
... Both concentrations and emissions of many air pollutants have been decreasing due to implement of control measures in China, in contrast to the fact that an increase in emissions of non-methane hydrocarbons (NMHCs) has been reported. This study employed seven years continuous NMHCs measurements and the related activities data of Shanghai, a megacity in China, to explore evolution of emissions and ...
... The cyclization–coupling reaction of 2-bromoaryl ketones and terminal alkynes is first realized by copper catalysis, which produces polyfunctional naphthyl aryl ethers in moderate to excellent yields with broad substrate scope and good functional group tolerance. This reaction proceeds via 6-endo-dig cyclization and C(sp²)–O coupling using green H₂O as the unique solvent and 5-bromopyrimidin-2-ami ...
... The rational electrolyte design with weak solvation is regarded as an effective way to regulate the electrolyte/electrode interface (SEI) that profoundly affects the performance of Li-metal batteries. Herein, we propose a newly developed siloxane-based weakly solvating electrolyte (SiBE) with contact ion pairs (CIPs) or aggregates (AGGs) dominating the solution structure, which enables the dendrit ...
... Chemically or physically distinct patches can be induced on the micelles of amphiphilic block copolymers, which facilitate directional binding for the creation of hierarchical structures. Hence, control over the direction of patches on the micelles is a crucial factor to attain the directionality on the interactions between the micelles, particularly for generating colloidal molecules mimicking th ...
... The essence behind metal solvent extraction is the interaction between metal species and organic extractants. Aqueous metal species tuning at the molecular level is critical to improve the extraction efficiency and selectivity of the target metal. Herein, we demonstrate a quantitative metal species tuning strategy which is capable of extracting the most critical metals (e.g., V, W, and Mo) in extr ...
solvents, etc ; countercurrent chromatography; separation; Show all 3 Subjects
Abstract:
... In counter‐current chromatography, the separation efficiency greatly depends on the partitioning ability of the separated substance between the stationary phase and the mobile phase. Partitioning ability is mainly represented by the parameter partition coefficient which is one of the important parameters to evaluate the separation effect of counter‐current chromatography. The scope of the partitio ...
... In this study, a series of non-fused thiophene ring-based small molecular acceptors (4T1–4T7) of A-D-A type are developed by the replacement of the end-groups of the 4TR molecule. The optoelectronic characteristics of the 4TR and 4T1–4T7 molecules are investigated employing the MPW1PW91 functional with the 6-31G (d,p) basis set, and solvent-state computations are studied using the TD-SCF. All the ...
... A metal-free and unprecedented strategy has been established for the construction of S-alkyl phosphorothioates through visible-light-driven four-component reactions of α-diazoesters, cyclic ethers, elemental sulfur and H-phosphonates. This strategy simply utilizes DBU as additive and elemental sulfur as the cheap and odorless sulfur source, providing an efficient and attractive approach to access ...
solvents, etc ; carbon; carbonates; electrolytes; phosphates; Show all 5 Subjects
Abstract:
... We introduce a fire-retarding phosphate-based electrolyte, 1 M NaBF₄ in triethyl phosphate with 3% vinylene carbonate as an SEI-forming additive, for sodium-ion batteries. With this electrolyte formulation, we achieved stable cycling performance with a capacity of 80.5 mA h g⁻¹ and a retention of 77.8% after 200 cycles in the Na-ion full cell of Na₃.₂V₁.₈Zn₀.₂(PO₄)₃vs. hard carbon. ...
... Electromembrane extraction (EME) is an extraction method on the micro scale, in which charged compounds are extracted from a donor phase (sample solution) into an acceptor phase via a supported liquid membrane (SLM) containing a water-immiscible organic solvent. To enhance the extraction efficiency and selectivity in this method, some studies have focused on the modification of the SLM, and thus m ...
solvents, etc ; cold; convection; prediction; temperature; Show all 5 Subjects
Abstract:
... The thermophoretic motion of nonionic colloids in an inhomogeneous temperature field is due to the solvent–colloid dispersion interactions. The latter form an attractive near-particle “gravity” field that leads to sinking of the colder solvent layers toward a colloid. The spatial extension of this microconvective motion is comparable to the size of the colloids, which prove to be small enough to o ...
solvents, etc ; droplets; imbibition; nanopores; photons; Show all 5 Subjects
Abstract:
... Hypothesis Self-assembly of colloidal particles enables the versatile fabrication of highly ordered structures and materials for optical, sensing, and other applications. Nevertheless, many traditional assembly processes are inefficient, because there exists an inevitable contradiction between time efficiency and crystalline quality. In this work, we introduce an ultrafast, robust, and scalable ap ...
solvents, etc ; aqueous solutions; computers; dissociation; Show all 4 Subjects
Abstract:
... We study NaCl ion-pair dissociation in a dilute aqueous solution using computer simulations both for the full system with long-range Coulomb interactions and for a well-chosen reference system with short-range intermolecular interactions. Analyzing results using concepts from Local Molecular Field (LMF) theory and the recently proposed AI-based analysis tool “State predictive information bottlenec ...
... In conventional classification, soft robots feature mechanical compliance as the main distinguishing factor from traditional robots made of rigid materials. Recent advances in functional soft materials have facilitated the emergence of a new class of soft robots capable of tether-free actuation in response to external stimuli such as heat, light, solvent, or electric or magnetic field. Among the v ...
... Stimuli-responsive organic materials with controllable luminescence are of enormous importance because of their potential applications in sensing, data security, and display devices. In this study, a multistimuli-responsive squaraine dyad (SQ-d) composed of two rigid squaraine moieties and a flexible ethylene linker was rationally designed and synthesized. SQ-d exhibits polymorphic luminescence, w ...
... Two types of unprecedented organic phosphine-catalyzed trifunctionalization of ynones have been achieved under mild and environmentally benign conditions using ⁱPrOH as the solvent, delivering a range of synthetically valuable acyloxy allylidene malonates and γ-alkylidenebutenolides in good yields with high stereoselectivities. A series of uncommon bond cleavage and bond formation processes have b ...
solvents, etc ; energy; fabrics; solubilization; thermoplastics; Show all 5 Subjects
Abstract:
... Integration of piezoelectric materials in composite and textile structures is promising for creating smart textiles with sensing or energy harvesting functionalities. The most direct integration that combines wearability, comfort, and piezoelectric efficiency consists of using fibers made of piezoelectric materials. The latter include inorganic ceramics or organic polymers. Ceramics have outstandi ...