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... Vacuum ultraviolet (VUV) photolysis is recognized as an environmental-friendly treatment process. Nitrate (NO₃⁻) and natural organic matter (NOM) are widely present in water source. We investigated trichloronitromethane (TCNM) formation during chlorination after VUV photolysis, because TCNM is an unregulated highly toxic disinfection byproduct. In this study: (1) we found reactive nitrogen species ...
byproducts, etc ; environment; ovens; wastewater treatment; Show all 4 Subjects
Abstract:
... Currently, the characteristics of volatile organic compounds (VOC) released from coking industry are still vague, and the widely used VOC emission factors (EFs) were still from the measurements of 1990s. Hence, focusing on coking industry, we conducted an in-situ measurement campaign in several typical plants, developed a set of VOC EFs for various release units, and estimated the current emission ...
byproducts, etc ; benzaldehyde; hydrogen; oxidation; oxygen; Show all 5 Subjects
Abstract:
... Here a palladium-catalyzed oxidation method for converting alkylarenes into the aromatic ketones or benzaldehydes with water as the only oxygen donor is reported. This C–H bond oxidation functionalization does not require other oxidants and hydrogen acceptors, and H₂ is the only byproduct. The oxygen atom introduced into the products is confirmed to be from water by the MS analysis on the product ...
byproducts, etc ; biosynthesis; density functional theory; Show all 3 Subjects
Abstract:
... Synthetic approaches to bicyclo[4.2.0]octadiene natural products frequently employ the synthesis of linear tetraenes to initiate a biosynthetic 8π/6π-electrocyclization cascade. This work forges a functionalized bicyclo[4.2.0]octadiene in two steps from cyclooctatetraene. The versatility of this method is demonstrated through natural product synthesis, including the first total synthesis of kingia ...
byproducts, etc ; alkanes; physical chemistry; spectroscopy; temperature; Show all 5 Subjects
Abstract:
... Although long-chain aliphatic hydrocarbons are documented in meteorites, their origin is poorly understood. A key question is whether they are pristine or a byproduct of terrestrial alteration? To understand if these long-chain hydrocarbons are indigenous, it will be important to explore their thermodynamic and mechanical stability at conditions experienced by extraterrestrial objects during atmos ...
byproducts, etc ; bioeconomics; sewage sludge; wastewater treatment; Show all 4 Subjects
Abstract:
... Being an inevitable byproduct of the operation of wastewater treatment plants (WWTPs), sewage sludge may cause serious environmental problems. Thus, the proper treatment and management of such waste is currently a challenge of great importance. Due to the significant concentration of various contaminants, the direct application of sewage sludge in agriculture is often limited. Nevertheless, this w ...
byproducts, etc ; condensates; convection; silicon; solidification; temperature; Show all 6 Subjects
Abstract:
... Silicon scraps, as the by-product of solar cells, have received more and more attention for its recycling with the continuing development of the cleaner production. However, hard particles and metal impurities in the silicon scraps are always difficult to remove deeply in industry. In this paper, electron beam melting coupled with directional solidification was used to purify silicon scraps and a ...
... Drilling cuttings, the primary byproduct from the exploration and mining of shale gas, are potentially hazardous wastes that are associated with the serious depletion of land resources and environmental safety problems. In this work, the distribution of polycyclic aromatic hydrocarbons (PAHs) in oil-based residues of shale gas drilling cuttings was studied. Furthermore, a column leaching test was ...
byproducts, etc ; Escherichia coli; acetates; energy; metabolism; transcriptomics; Show all 6 Subjects
Abstract:
... A novel Escherichia coli efficient expression system had been constructed in our previous study. The system was based on the overexpression of endogenous genes prpD and malK to enhance the expression of exogenous genes. In this study, a general regulatory mechanism of prpD and malK was first revealed through transcriptome analysis and many experimental verifications. We surprisingly proved that ov ...
byproducts, etc ; alkenes; carbon dioxide; enantioselectivity; ligands; rhodium; Show all 6 Subjects
Abstract:
... Through the initial screening and further rational design of chiral cyclopentadienyl ligands, a chiral rhodium-catalyzed enantioselective 1,2-carboamidation of aromatic tethered alkenes was developed, enabling the asymmetric preparation of various chiral 2,3-dihydro-3-benzofuranmethanamides with an enantioenriched all-carbon quaternary center at the β position of amide. This robust transformation ...
byproducts, etc ; endophytes; evolution; host plants; mutualism; saprotrophs; symbionts; Show all 7 Subjects
Abstract:
... Plant roots are abundantly colonized by dark septate endophytic (DSE) fungi in virtually all ecosystems. DSE fungi are functionally heterogeneous and their relationships with plants range from antagonistic to mutualistic. Here, we consider the role of by-product benefits in DSE and other root–fungal symbioses. We compared host investments against symbiont-derived benefits for the host plant and ca ...
byproducts, etc ; cement; fly ash; sludge; toxicity; wastewater treatment; Show all 6 Subjects
Abstract:
... Controlled low-strength material (CLSM), a widely used replacement for conventional compacted filling material, is self-leveling and self-compacting, currently used in many structural applications. The properties of a CLSM mixture made from cement, fly ash, and waste water treatment sludge (WTS) were examined in this study. The CLSM mixtures were prepared using several water-to-binder (w/b) ratios ...
byproducts, etc ; locomotion; models; ontogeny; parentage; phenotype; probability; wind; Show all 8 Subjects
Abstract:
... Dispersal emerges as a consequence of how an individual's phenotype interacts with the environment. Not all dispersing individuals have the same phenotype, and variation among individuals can generate complex variation in the distribution of dispersal distances and directions. While active locomotion performance is an obvious candidate for a dispersal phenotype, its effects on dispersal are diffic ...
byproducts, etc ; liquids; ozone; ozone depletion; solar radiation; stratosphere; Show all 6 Subjects
Abstract:
... Polar stratospheric clouds (PSCs), of which the surface is a dynamic liquid water layer and might consist of aqueous HNO₃ and H₂O₂, is a well-known key meteorological condition contributing to the ozone hole in the polar stratosphere. PSCs has been considered to provide abundant surface for the heterogeneous reactions causing the formation of the Cl₂ and HOCl, which are further photolyzed into Cl ...
byproducts, etc ; carbon dioxide; composite polymers; hydrophilicity; nanopores; porosity; ultrafiltration; Show all 7 Subjects
Abstract:
... Due to the predominance of CO₂ as a new trigger with source abundance, non-toxicity, good reversibility and no byproduct accumulation compared to other triggers, CO₂-responsive membranes recently attract wide interest in stimuli-switchable separation. Here we report on the development of CO₂-responsive nanoporous membranes with poly(2-dimethylaminoethyl methacrylate)-block-polystyrene (PDMAEMA-b-P ...
byproducts, etc ; ambient temperature; disulfides; electrochemistry; electrolytes; electrosynthesis; hydrogen; sulfur; Show all 8 Subjects
Abstract:
... An electrochemical oxidative synthesis of S-thiocarbamates by a carbamothioation reaction via a three-component coupling reaction (disulfide, water and isocyanide) is developed, which avoids the use of external oxidants and generates only hydrogen gas as the by-product. With NH₄I as the mediator and electrolyte, the desired S-thiocarbamates were obtained in good yields in an undivided cell at room ...
byproducts, etc ; alcoholysis; biodiesel; carbonates; glycerol; hydrotalcite; process design; urea; Show all 8 Subjects
Abstract:
... Glycerol carbonate is an important chemical in industrial chemistry. It could be synthesized from glycerol, which is a byproduct in the biodiesel production process. Alcoholysis of urea with glycerol is a promising approach for the synthesis of glycerol carbonate. Catalysts are indispensable for the reaction of alcoholysis of urea with glycerol. Summarizing the developed catalysts and unraveling t ...
byproducts, etc ; Vitis vinifera; cultivars; food chemistry; grapes; stilbenoids; vineyards; Show all 7 Subjects
Abstract:
... Stilbenoids in grape cane (Vitis vinifera L.) are bioactive compounds relevant for plant defense and the potential valorization of this byproduct. Our screening of grape cane from 102 varieties showed constitutive stilbenoid levels in a wide range (557–7748 mg/kg of dry weight). Analyses of genetically distinct clones of selected cultivars unraveled that intravarietal variability (e.g., cv. Riesli ...
byproducts, etc ; ambient temperature; carbon; carbon fibers; ceramics; humidity; microstructure; slurries; Show all 8 Subjects
Abstract:
... Continuous carbon fibre ceramic matrix composites capable of tolerating multiple thermal-shock cycles and resisting ablation are needed for aerospace and hypersonic systems. Carbon fibre around 50 vol% and ultra-refractory matrices are fundamental parameters. The influence of rare earth (RE) oxides on the microstructure and mechanical properties of carbon fibre-ZrB₂/SiC composites was investigated ...
byproducts, etc ; biofiltration; biomass production; environmental science; human health; photolysis; toxicity; Show all 7 Subjects
Abstract:
... The continuous emissions of volatile organic compounds (VOCs) from the industrial process cause serious environmental problems and pose a threat to human health. Photodegradation technology and biofiltration technology are efficient to control VOCs emissions. Recently, the researches on combined photodegradation and biofiltration technology have been attractive, since it could overcome the challen ...