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... The high NO₃⁻ concentration in fine particulate matters (PM₂.₅) during heavy haze events has attracted much attention, but the formation mechanism of nitrates remains largely uncertain, especially concerning heterogeneous uptake of NOX by aqueous phase. In this work, the heterogeneous uptake of NO₂ by sodium acetate (NaAc) droplets with different NO₂ concentrations and relative humidity (RH) condi ...
acetates, etc ; Acidaminococcus; Clostridium; anaerobic digestion; biogas; biotransformation; carbon dioxide; energy; environment; gas production (biological); hydrogen; iron; liquids; markets; microbial activity; microbial communities; microbiome; polymers; synergism; Show all 19 Subjects
Abstract:
... Hydrogen (H₂) assisted ex-situ biogas upgrading and liquid chemicals production can augment the fossil fuel-dominated energy market, and alleviate CO₂-induced global warming. Recent investigations confirmed that nanoscale zero-valent iron (nZVI) enabled the enhancement of anaerobic digestion for biogas production. However, little is known about the effect of nZVI on the downstream ex-situ biogas u ...
... The increasing application of anammox processes suggests their enormous potential for nitrogen removal in wastewater treatment facilities. However, the functional potentials and ecological differentiation of cooccurring anammox species in complex ecosystems have not been well elucidated. Herein, by utilizing functional reconstruction and comparative genome analysis, we deciphered the cooccurring m ...
Luan V. Meirelles; Pedro P. de Castro; Saulo T. A. Passos; Bernardo B. P. P. Carvalho; Chris H. J. Franco; José R. Correa; Brenno A. D. Neto; Giovanni W. Amarante
... A transition metal-free protocol for the preparation of fluorescent and non-fluoresent 3-methylthio-4-arylmaleimides in a single step through a new rearrangement from thiazolidine-2,4-diones is described. By employing the optimized reaction conditions, a broad scope of derivatives was prepared in ≤97% yield. The reaction tolerated several substituted aryl groups, including the challenging preparat ...
... Several studies have reported that current produced by electro-active bacteria (EAB) is dependent on anode potential and substrate concentration. However, information about the relation between biofilm growth and current density is scarce. In this study, biofilm thickness was monitored in-situ and this relation explored at three anode potentials and three acetate concentrations. The highest curren ...
... Synthesis of highly strained fused substituted dihydrobenzopyran cyclopropyl lactones derived from coumarin carboxylates are reported. The substrate scope tolerates a variety of 6- and 8-substituents on the coumarin ring. Substitution at the 5- or 7-position is resistant to tricyclic lactone formation except with 7-methyl substitution. Benzamide-containing coumarins afford the tricyclic ketal. A p ...
acetates, etc ; electric potential difference; lighting; Show all 3 Subjects
Abstract:
... Wide-bandgap perovskites as a class of promising top-cell materials have shown great promise in constructing efficient perovskite-based tandem solar cells, but their intrinsic relatively low radiative efficiency results in a large open-circuit voltage (VOC) deficit and thereby limits the whole device performance. Reducing film flaws or optimizing interfacial energy level alignments in wide-bandgap ...
... Petit Verdot is widely used in blend wines but only few studies focus on the effect of microorganisms on the aroma formation of its monovarietal wine. This study explored the correlation between microorganisms and aromas during spontaneous fermentation (SF) and inoculated fermentation (IF). The changes of volatile compounds and microbial succession during the wine fermentation were monitored by HS ...
... Herein, we compared the effect of different extra iron and sulfur precursors on the sulfidation efficiency, physicochemical properties, and reactivity of post-sulfidated microscale zero-valent iron (S-ZVI). S⁰@ZVI was synthesized from in situ S⁰ generated via reaction of Fe(III) with S²⁻, which resulted in 23-fold higher Cr(VI) removal compared with S⁰cₒₘ/ZVI synthesized using commercial S⁰. The d ...
acetates, etc ; crystallization; formates; industrialization; propionic acid; Show all 5 Subjects
Abstract:
... As a green solvent, ionic liquids (ILs) are considered as a promising alternative to conventional polar aprotic solvents for the production of efficient and stable perovskite solar cells (PSCs). Moreover, with the use of IL solvents, perovskite films can be prepared without antisolvent treatments in an ambient environment instead of in a glovebox with inert gases, which simplifies the film manufac ...
acetates, etc ; amylose; cellulose; enantiomers; glycopeptides; vancomycin; Show all 6 Subjects
Abstract:
... To extend our previous studies concerning the enantioseparation of 4C-substituted pyrrolidin-2-one derivatives on polysaccharide-based chiral stationary phases with ethanol/n-hexane mobile phases, two commercially available immobilized chiral stationary phases [amylose derivatized with (S)-α-methylbenzylcarbamate, and cellulose derivatized with 3,5-dichlorophenylcarbamate] were studied. Also, effo ...
... High reactivity of trimethoxyphenyl (TMP)-iodonium(III) acetate for phenol O-arylation was achieved. It was first determined that the TMP ligand and acetate anion cooperatively enhance the electrophilic reactivity toward phenol oxygen atoms. The proposed method provides access to various diaryl ethers in significantly higher yields than the previously reported techniques. Various functional groups ...
acetates, etc ; liquids; permeability; plasticizers; vinyl acetate; Show all 5 Subjects
Abstract:
... Polymer inclusion membranes (PIMs) are far investigated for their ability to extract heavy metals and small organic compounds from aqueous media. Polyvinyl chloride (PVC) is one of the most widely used base polymers for the PIM elaboration. However, its use requires the incorporation of a relatively expensive liquid plasticizer. In the present work, poly(ethylene-co-vinyl acetate) (EVA) serves as ...
acetates, etc ; deprotonation; ethanol; glucosamine; uranyl ions; Show all 5 Subjects
Abstract:
... Reaction of 1,3,4,6-tetra-O-acetyl-N-(2-hydroxy)-naphthylidene glucosamine (HL(Ac)) with uranyl acetate in ethanol leads to formation of dinuclear [(UO₂)₂(L)₂] (1). In a second step 1 is quantitatively transferred into the trinuclear oxo-bridged complex [(UO₂)₃(μ₃–O)(L)₃]²⁻ (2²⁻) via deprotonation and coordination of a water molecule. This transformation was followed by NMR and UV/Vis spectroscopy ...
acetates, etc ; databases; exhibitions; journals; organic chemistry; Show all 5 Subjects
Abstract:
... Scatter plot analyses for 14,169 phenylethanes of the substructure Cᵦ-CαH₂-Ph with three open coordination positions at Cᵦ and 150,568 phenylethanes of Cᵦ-CαHX-Ph with an additional open coordination position X at Cα have been performed, based on searches in the Cambridge Structural Database. The correlation of rotation angle ψ = Cᵦ–Cα–Cᵢ–Cₒ with a pyramidalization angle θ = Cₒ–Cₒ′–Cᵢ–Cα in a 360° ...
acetates, etc ; iron; nanosheets; ultrasonic treatment; ultrasonics; Show all 5 Subjects
Abstract:
... The properties of sulfidated zero-valent iron (S-ZVI) are considered to be determined by the entire structure of Fe⁰ and FeₓSy as a whole, but few studies focus on the influence of the morphology and structure of the external FeₓSy layer on the performance of S-ZVI. In this study, after the sulfidation of microscale ZVI in acetate (HAc-NaAc) and 2-(N-morpholino) ethanesulfonic acid (MES) buffer so ...
acetates, etc ; gel chromatography; ginger; research; sesquiterpenoids; Show all 5 Subjects
Abstract:
... A new eusdesmane sesquiterpenoid, characterised as 5-acetoxy-9aβ-hydroxy-4aαH-3,5α, 8aβ-trimethyl-4, 4a, 6, 7, 8a, 9-hexahydronaphtho-([2, 3 b]-dihydrofuran-2-one)-8-one or phaeusmane F acetate (1) has been isolated from the rhizomes of the South African variety of wild ginger (iphonochilus aethiopicus (Schweinf) B.L. Burtt). The compound was obtained after a series of column and gel filtration ch ...
acetates, etc ; Bacteroides; Clostridium; Escherichia; Lachnospiraceae; Pulsatilla; blood serum; body weight; dextran; enzyme-linked immunosorbent assay; gas chromatography-mass spectrometry; genes; homeostasis; interleukin-10; interleukin-17; intestinal microorganisms; intestines; males; mechanism of action; metabolism; models; occludins; propionic acid; short chain fatty acids; sodium sulfate; therapeutics; tight junctions; traditional medicine; tumor necrosis factor-alpha; ulcerative colitis; Show all 30 Subjects
Abstract:
... Pulsatilla decoction (PD), is an herbal formula commonly used for the treatment of ulcerative colitis (UC) in clinical practice, but the mechanism of PD alters the colitis remains elusive. To evaluate the intervention effect of PD on Dextran Sodium Sulfate (DSS)-induced UC based on gut microbiota and intestinal short-chain fatty acid (SCFAs) metabolism, and to investigate the mechanism of action o ...
acetates, etc ; Alpinia galanga; formic acid; nanoemulsions; solvents; Show all 5 Subjects
Abstract:
... An isocratic RP-HPLC was developed and validated for isolation of 1΄-Acetoxychavicol acetate (ACA) from Alpinia galanga extract (AGE). Nucleodur C18 column was used as the stationary phase and mixture of acetonitrile/0.1% formic acid in water (60/40, v/v) were used as mobile phase. The elution was carried out with a flow rate of 1 mL/min. Further, the method was validated as per ICH Q2 [R1] guidel ...
acetates, etc ; enol ethers; mannose; moieties; organic chemistry; Show all 5 Subjects
Abstract:
... Carbohydrate-based oxepines are seven-membered-ring oxacycles containing an enol ether moiety. These compounds have been used as intermediates in the preparation of septanose carbohydrates by functionalization through their double bond. Reported here is a new synthesis of a carbohydrate based oxepine that uses 2,3;4,6-di-O-acetonide mannose as a key starting material. The oxepine is an important p ...