Acid Bis Research Articles

Structure and vibrational features of the protic ionic liquid 1,8-diazabicyclo[5.4.0]-undec-7-ene-8-ium bis(trifluoromethanesulfonyl)amide, [DBUH][TFSI

The Protic Ionic Liquid (PIL) formed by neutralization of the super-strong base 1,7-diazabicyclo[5.4.0]undec-7-ene (DBU) with the super-strong acid bis(trifluoromethanesulfonyl)-imide (TFSI), indicated as [DBUH][TFSI], has been investigated. Its chemical physical properties and structural features have been explored using a synergy of experimental and computational tools. Molecular Dynamics-rationalised X-ray diffraction patterns highlight the major role played by hydrogen bonding (HB) in affecting morphology in this PIL. A comparison between HB features in this and in related PILs has been presented, on the base of far-IR experiments and DFT analysis. Indications of a weaker HB interaction in [DBUH][TFSI] in comparison with [DBUH][TfO], consistently with their ΔpKa difference, have been observed and rationalised in terms of geometrical properties of the main conformers contributing to the experimental spectra. In the liquid phase of [DBUH][TFSI] a particularly large conformational disorder is observed and the corresponding large dispersion of the frequencies of the HB stretching modes leads to a broad absorption band without a well defined peak. On the contrary, well detectable HB related absorptions are observable in the solid phase of [DBUH][TFSI] and at all temperatures in [DBU][TfO], where less configurational disorder occurs.

GC-MS ANALYSIS OF THREE PLANTS ESSENTIAL OILS AND THEIR EFFECT ON BACTERIAL SPOT DISEASE OF TOMATO

The aim of this present study is to evaluate the antimicrobial activities of three plants essential oils, Nigella (Nigella sativa), Eucalyptus (Cinnamomum camphora) and clove (Syzygium aromaticum) against plant pathogenic bacteria Xanthomonas vesicatoria and their influences on controlling the bacterial spot disease of tomato plants. The chemical composition of the oils was calculated by gas chromatograph/mass spectrometer (GC/MS) analysis. The results revealed that the major constituents of Nigella oil were fatty acid i.e. oleic acid (4.09%%), Fumaric acid (0.13%), Palmitic acid (4.95-1.65 %), Octadec-9-enoic acid (0.53%), myristic acid (0.78%), Cyclohexadecane (0.01%) and Hexanedioic acid bis (2-ethylhexyl) ester (75.02%). In addition, the main components of Eucalyptus oil were D-camphor (40.01%), linalool (20.57%), and cineole (10.86%). The chemical analysis showed also that clove oil contained eugenol (22.94%), eugenyl acetate (16.65%), caryophyllene (10.37 %) and 2-Pyridineethanol (6.08 %). In in vitro bioassay against X.anthomonas vesicatoria, the results demonstrated that among the three tested plant oils, Eucalyptus oil (10 %) recorded the maximum value was (1.73 cm) bacterial inhibition zone followed by Clove oil (1.50 cm). Results also showed spraying plants with the tested essential oils two days before bacterial inoculation recorded the lowest disease index comparing to the treatment where plants were treating with essential oils two days after bacterial inoculation. The obtained results also clearly illustrated that, Peroxidase (PO), polyphenoloxidase PPO and chitinase activities increased as a result of spraying tomato plants with the tested oils. Moreover, protein analysis confirmed that new protein bands with low molecular weight had a progressive relationship with reduction of bacterial spot disease severity on plants treated with the tested oils.

Synthesis and Reactions of 1,3,5-Tri- and 1,3,5,7-Tetracarbonyl Compounds

AbstractThe reaction of 1,3-bis(silyloxy)-1,3-butadienes with functionalized and nonfunctionalized acid chlorides and bis(acid chlorides) gives rise to the formation of a great variety of 1,3,5-tri- and 1,3,5,7-tetracarbonyl compounds and cyclic products derived from them. Examples include functionalized and nonfunctionalized 3,5-dioxopentanoates, 3,5-dioxopimelates, 3-alkylidene-3H-isobenzofuran-1-ones, salicylates, 3(2H)furanones, and 3-oxo-4-sulfonylesters. Methylation and cyclopropanation reactions of 1,3,5-tri- and 1,3,5,7-tetracarbonyl compounds do not provide access to the expected permethylated and cyclopropanated polycarbonyl compounds. However, the latter could be prepared by stepwise protocols. The reaction of 1,3,5-tri- and 1,3,5,7-tetracarbonyl compounds with dinucleophiles resulted in cyclization reactions to give a variety of heterocyclic structures.1 Introduction2 Reactions of 1,3-Bis(silyloxy)-1,3-butadienes with Acid Chlorides3 Reactions of 1,3,5-Tri- and 1,3,5,7-Tetracarbonyl Compounds4 Conclusion

Double molecular recognition ligands modified CPDS/CMCS/Fe3O4-rGO hybrid with enhanced enrichment capacity for glycoproteins at neutral environment

Abstract In order to achieve specific enrichment of target glycoproteins, double molecular recognition ligands functionalized surface solid-phase adsorption materials that can play a role under physiological pH conditions, have obvious advantages. In this work, a novel strategy was proposed for the synthesis of double molecular recognition functionalized magnetic graphene nanocomposites. Horseradish peroxidase was selected as the template proteins for evaluating the selectivity and binding capacity of the adsorption material. The bimolecular recognition was realized by introducing 4-carboxyphenylboronic acid (CPBA) and Suberic acid bis(3-sulfo-N-hydroxysuccinimide ester) sodium salt (Sulfo-DSS) as functional ligands. The abundant oxygen-containing groups in the complex (abbreviated as CPDS/CMCS/Fe3O4-rGO) were beneficial to reduce the pKa value of CPBA. Finally, CPDS/CMCS/Fe3O4-rGO realized the selective adsorption of glycoproteins in the neutral environment (pH 7.0). The resultant CPDS/CMCS/Fe3O4-rGO exhibited a high adsorption capacity of 1280.6 mg g−1 and excellent specificity toward glycoproteins compared to nonglycoproteins. Moreover, CPDS/CMCS/Fe3O4-rGO with strong magnetic responses (59.29 emu·g−1), could achieve rapid aggregation and separation under the external magnetic field. The results demonstrated the great potential of CPDS/CMCS/Fe3O4-rGO composites to separate and enrich glycoproteins from the complex biological sample for the glycoproteins analysis.

Removal of Hg2+ and CH3Hg+ by a polyphosphonate ligand from water

The potential of employing a polyphosphonate ligand, diethylenetriamine-N,N,N′,N″,N″-pentakis(methylenephosphonic) acid (DTPMP), in the removal from water of Hg2+ and (CH3)Hg+ was studied. Metal-ligand systems were investigated by potentiometry in aqueous solution at t = 25°C, 0.1 < I / mol L1 < 1 for Hg2+, I = 0.1 mol L1 for (CH3)Hg+. The formation of several complex species was evidenced. The analysis of the results showed that species stability of Hg2+ complex species was significantly higher than that of (CH3)Hg+. The sequestering capacity, determined under typical conditions of natural waters, showed highest potential towards Hg 2+ , also respect to those of other polyphosphonate ligand, such as etidronic acid ((1-Hydroxy-1,1-ethanediyl)bis(phosphonic) acid, HEDPA). This quantitative study is useful to evaluate the possible employment of this polyphosphonate in the decontamination of natural waters from toxic metals.

Echinops taeckholmiana Amin: Optimization of a Tissue Culture Protocol, Biological Evaluation, and Chemical Profiling Using GC and LC-MS.

There have been no reports published on the rare Echinops taeckholmiana growing wildly in Egypt. So, this study aimed to preserve it through method optimization of in vitro seed germination, besides callus formation from induced seedlings. Chemical profiling using gas chromatography-mass spectrometry (GC-MS) analysis of the n-hexane fraction afforded 29 identified components, mainly fatty acids esters, sesquiterpenes, triterpenes, one thiophene, and bis(2-ethylhexyl) phthalate. Ultra-performance liquid chromatography-electron spray ionization/tandem mass spectrometry (UPLC-ESI/MS-MS) analysis of total alcoholic root and induced calli extracts resulted in 68 metabolites. Taraxeryl acetate, β-sitosterol, stigmasterol-3β-d-glucoside, and 1,1,1-kestopentaose were identified from the defatted root extract, which inhibited α-amylase (IC50 54.6 μg/mL) and α-glucosidase (60.4 μg/mL) enzymes compared with acarbose (IC50 values of 30.57 and 34.71 μg/mL, respectively). Moreover, it showed moderate activity against HepG2 (IC50 31.1 ± 1.4 μg/mL) and no activity against M-NFS-60 cell lines compared to cisplatin (IC50 3.25 ± 1.4 and 8.37 ± 0.25, respectively).

Allelochemicals Analysis of Rumex vesicarius L. and Zygophyllum coccineum L., and Their Effect on Seed Germination and Seedling Growth of Wheat, Triticum aestivum L.

Plants samples were gathered from Ramadi, University of Anbar. Extraction processes performed from foliage in labs belonging to Center for Desert Studies using methanolic and aqueous extracts to assess their Allelopathy. Allelopathic bioassay applied with three concentrations 0.5, 1 and 2% On Germination%, Germination Rate, Germination Speed, Average Germination Speed, Response Index, Radicle and Plumule Length of wheat seed. Phytochemicals detection of the R. vesicarius presented highest percentage of alkaloids, flavonoids, phenols and Glycosides. GC/MS analysis proofed that R. vesicarius and Z. coccineum methanolic extracts contained highest 2-pyrrolidone-5-carboxylic acid (alkaloid) of 35.98% and 1,2-benzendicarboxyylic acid bis(-methylhexyl) ester (hydrocarbonate chain) of 35.06%, in each species extract, respectively. Methanolic and aqueous extract (%2) of R. vesicarius possessed lowest rate of germination (%13.3), (%50.7), respectively. On the other hand, methanolic and aqueous extract (%2) of Z. coccineum gave lowest germination rate of 30.6 and 81.3%, respectively. so, this extracts of R. vesicarius and Z. coccineum could be used as eco-friendly bioherbicide, and may be integrated into harmful weed control strategies.

Aqueous N-H acid bis(trifluoromethylsulfonyl) imide Solution - [C4mim][Tf2N] Ionic Liquid Biphasic System: an Original Investigation by Diffusion Ordered Spectroscopy Nuclear Magnetic Resonance

Transfers of solutes from an aqueous solution to an ionic liquid and vice versa has been well studied for years. On the other hand, influence of transferred solutes on the ionic liquid's network is not yet evaluated. Therefore, we focus on the aqueous - ionic liquid biphasic system composed of two immiscible solutions containing N-H acid bis(trifluoromethylsulfonyl) imide and [C4mim][Tf2N] ionic liquid. After mixing and separation of the two phases, a part of water, H3O+, [Tf2N−] and H[Tf2N] anions are transferred into [C4mim][Tf2N] ionic liquid because H[Tf2N] has a salting in effect. The presence of this solutes might modify the local structure of [C4mim][Tf2N] ionic liquid. So far, our goal is to evaluate this structural change using several tools. For this, one dimensional 1H, 19F and Diffusion Ordered Spectroscopy Nuclear Magnetic Resonance were carried out on [C4mim][Tf2N] ionic liquid. We observed that some of water molecules are free and formed local microstructure as water pocket inside the ionic liquid network. The others are hydrogen bonded to [Tf2N−] anions as Tf2N−….H-O-D….Tf2N− for example. As long as the mole fraction of water in the ionic liquid remains less than or equal to that of [C4mim+] or [Tf2N−] the structure of the network is maintained. Free water moves at its own speed and bound water is an inclusion in the [C4mim][Tf2N] network. As soon as the mole fraction of the water is greater than that of [C4mim+] or [Tf2N−], the network of [C4mim][Tf2N] ionic liquid is gradually dislocated. Charged clusters composed with [C4mim+], [Tf2N−] and bond water are build and free water flow between them.

Terephthalic Acid Bis-(2-ethylhexyl) Ester; an Isomeric Phthalate from Deinbollia pinnata Leaves

The family Sapindaceae are tropical and sub-tropical continental plants. In this study, terephthalic acid bis-(2-ethylhexyl) ester (1) and phthalic acid bis-(2-ethylhexyl) ester (2) were isolated as isomeric compounds from the ethanolic leaf extracts of Deinbollia pinnata for the first time together with methyl gallate (3), ethyl gallate (4), and pyrogallol (5). The separation of the isomeric mixture was by freezing the sub-fraction with methanol for seventy-two hours; followed by filtration, isolation, and purification.

Oxovanadium(IV) Complex with 1-Hydroxyethane-1,1-Diphosphonic Acid and Bis(2-pyridyl-1,2,4-Triazol-3-yl)methane

The synthesis of oxovanadium(IV) complex with 1-hydroxyethane-1,1-diphosphonic acid (H4EDP) anion and bis(2-pyridyl-1,2,4-triazol-3-yl)methane (H2L) is described. The reaction of VOSO4 with H4EDP and H2L followed by neutralization of the reaction mixture with Et3N gives the trinuclear complex [(VO)4(H2L)2(EDP)2(H2O)2]·4H2O (I), which was studied by IR and ESR spectroscopy. The molecular and crystal structures of complex I were determined by X-ray diffraction (CIF file CCDC no. 2022772).

Differential dielectroscopic data on the relation of erythrocyte membrane skeleton to erythrocyte deformability and flicker.

Two dielectric relaxations, βsp (1.5MHz) and γ1sp (7MHz), have been detected on spectrin-based membrane skeleton (MS) of red blood cells (RBCs) using the plot of admittance changes at the spectrin denaturation temperature (Ivanov and Paarvanova in Bioelectrochemistry 110: 59-68, 2016, Electrochim Acta 317: 289-300, 2019a). In this study, we treated RBCs and RBC ghost membranes with agents that make membranes rigid and suppress membrane flicker, and studied the effect on βsp and γ1sp relaxations. Diamide (diazene dicarboxylic acid bis-(N,N-dimethylamide)) (up to 0.85mM), taurine mustard (tris(2-chloroethyl)amine) (up to 2mM), known to specifically cross-link and stiffen spectrin, and glutaraldehyde (up to 0.044%) all inhibited the relaxations in RBC ghost membranes. Similar inhibition was obtained resealing RBC ghost membranes with 2,3-diphosphoglicerate (up to 15mM), binding WGA (wheat germ agglutinin) (up to 0.025mg/ml) to exofacial aspect of RBCs, incubating RBCs in hypotonic (200mOsm) and hypertonic (600-900mOsm) media and depleting RBCs of ATP. By contrast, concanavalin A (1mg/ml) and DIDS (4,4'-diiso-thiocyanato stilbene-2,2'-disulfonic acid) (75μM, pH 8.2), both known to bind specifically band 3 integral protein of RBCs without effect on RBC membrane rigidity, did not affect the relaxations. We conclude there might be a relation between the strength of dielectric relaxations on MS spectrin and the deformability and flicker of RBC membrane.

Response of Trichogramma papilionis to semiochemicals induced by host oviposition on plants

Parasitoid wasps may rely on chemical volatiles from herbivorous insects and their plant hosts for finding their preferred host. This study was conducted to test the reaction of Trichogramma papilionis Nagarkatti (Hymenoptera: Trichogrammatidae) to chemical volatiles that from host eggs and egg infested plants. Several volatile compounds were selected, singly, and as combinations of chemicals to determine whether these volatile compound blends could enhance orientation responses of T. papilionis wasps toward the source of the stimulus. In a Y-tube olfactometer, female wasps were significantly attracted to only two chemical volatiles among the seven compounds tested. The compounds were: trans-isoeugenol, anisole, β-myrcene, cis-3-Hexenyl butyric acid (bis(2-ethylhexyl) phthalate, bis(2-ethylhexyl) phthalate, acetophenone, and α-farnesene (>95% purity). Only anisole and bis(2-ethylhexyl) phthalate were attractive to T. papilionis wasps when used separately in olfactometer experiments. The wasps showed a significant attraction to a blend of anisole and bis(2-ethylhexyl) phthalate at a ratio of 25 μL/100 μL. There was no significant response to the other bled ratios of that combination of chemicals. Greenhouse studies showed that the wasps were not significantly attracted to anisole alone, but exhibited short-distance attraction to the above blend.

Efficient Synthesis of Novel 1,3,4-Oxadiazoles Bearing a 4-N,N-Dimethylaminoquinazoline Scaffold via Palladium-Catalyzed Suzuki Cross-Coupling Reactions.

Two series of novel (symmetrical and unsymmetrical) quinazolinylphenyl-1,3,4-oxadiazole derivatives were synthesized using palladium-catalyzed Suzuki cross-coupling reactions. The presented synthetic methodology is based on the use of bromine-substituted 2-phenyl-4-N,N-dimethylaminoquinazolines and either a boronic acid pinacol ester or a diboronic acid bis(pinacol) ester of 2,5-diphenyl-1,3,4-oxadiazole. The reactions are conducted in a two-phase solvent system in the presence of catalytic amounts of [1,1′-bis(diphenylphosphino)ferrocene]-dichloropalladium(II), sodium carbonate, and tetrabutylammonium bromide, which plays the role of a phase-transfer catalyst. The luminescence properties of the obtained compounds are discussed in the context of applying these compounds in optoelectronics. Specifically, two highly-conjugated final products: N,N-dimethyl-2-phenyl-6-(4-(5-phenyl-1,3,4-oxadiazol-2-yl)phenyl)quinazolin-4-amine (8f) and 6,6′-(4,4′-(1,3,4-oxadiazole-2,5-diyl)bis(4,1-phenylene))bis(N,N-dimethylquinazolin-4-amine (9f), which contain a 1,3,4-oxadiazole moiety connected to a quinazoline ring by a 1,4-phenylene linker at the 6 position, exhibit strong fluorescence emission and high quantum yields.

Antibacterial activity of Mn(I) and Re(I) tricarbonyl complexes conjugated to a bile acid carrier molecule.

A bifunctional cholic acid-bis(2-pyridylmethyl)amine (bpa) ligand featuring an amide linker was coordinated to a manganese(i) or rhenium(i) tricarbonyl moiety to give [M(bpacholamide)(CO)3] with M = Mn, Re in good yield and very high purity. Strong antibacterial activity was observed against four strains of methicillin-susceptible (MSSA) and methicillin-resistant (MRSA) Staphylococcus aureus, with minimum inhibitory concentrations (MICs) in the range of 2-3.5 μM. No difference in response was observed for the MSSA vs. MRSA strains. Activity was also independent of the nature of the metal center, as the Mn and Re complexes showed essentially identical MIC values. In contrast to some other metal carbonyl complexes, the activity seems to be unrelated to the release of carbon monoxide, as photoactivation of the Mn complex reduced the potency by a factor of 2-8. Both metal complexes were non-toxic in Galleria mellonella larvae at concentrations of up to 100× the MIC value. In vivo testing in Galleria larvae infected with MRSA/MSSA demonstrated a significant increase in overall survival rates from 46% in the control to 88% in the group treated with the metal complexes. ICP-MS analysis showed that the Mn and Re cholamide complexes are efficiently internalized by E. coli cells and do not interfere with membrane integrity, as evident from a lack of release of intracellular ATP. An increased sensitivity was observed in acrB, acrD, and mdt mutants that are defective in multidrug exporters, indicating that the compounds have an intracellular mechanism of action. Furthermore, E. coli mntP mutants defective in the gene encoding an Mn exporter were more sensitive than the wildtype, while inactivation of the regulator that controls expression of the Mn uptake proteins MntP and MntH slightly increased sensitivity to the compound. Single knockout mutants defective in genes linked to bile salt and oxidative stress response (dinF, yiaH, sodA, katE, and soxS) did not show increased sensitivity relative to the wild type. Overall, neither the cholic acid moiety nor the metal-carbonyl fragment alone appear to be responsible for the biological activity observed and thus the search for the primary intracellular target continues.

Study on the Extraction and Separation of Samarium from Chloride Medium Using D2EHPA and [P66614][D2EHP] and Their Application to Monazite Ore

The present work deals with the investigation of solvent extraction of Sm(III) from chloride medium using di-(2-ethylhexyl)phosphoric acid (D2EHPA) and trihexyl tetradecyl phosphonium bis(2-ethylhexyl)phosphate ([P66614][D2EHP]) as extractants. In the extraction stage, the effect of contact time, aqueous phase pH, extractant concentration, NaCl concentration, temperature effect, stripping and O:A ratio variation are investigated to compare the extraction abilities of D2EHPA and the ionic liquid made from that. The complex formation ability and extraction mechanism of samarium with two extractants are explained by FTIR spectra and slope analysis method. Solvent extraction of samarium is better noticeable with D2EHPA than that of [P66614][D2EHP]. It is evident that with rise in pH of the aqueous medium, the extraction percentage of samarium is increased for both the extractants. Optimum extraction (100%) of Sm3+ is obtained with 0.1 mol/L D2EHPA and 0.1 mol/L [P66614][D2EHP], respectively. HNO3 is the best stripping agent for back-extraction of samarium from the loaded extractants. Separation studies are carried out in the presence of transition metal ions (mostly present in magnets) to know the efficiency of D2EHPA and ionic liquid [P66614][D2EHP]. The extraction studies with mixture of other rare earth metal ions similar to monazite composition follow the order as Gd(III) > Sm(III) > Nd(III) > Ce(III) > La(III) for both the extractants. Using 0.03 mol/L D2EHPA, complete separation of Gd and Sm from the rare earth mixtures is found at two stages with O:A ratio of unity.

Etidronic acid adduct and bis (2-pyridyl-1,2,4-triazolyl-3) butane: properties and effect on pain sensitivity

The article presents the results of experimental studies on the effect of etidrononic acid adduct and bis(2-pyridyl-1,2,4-triazolyl-3)butane (EA+BTB) on the pain sensitivity of male and female rats. This substance is created on the precursors basis, which have a pronounced analgesic activity in acute pain when injected once into male and female rats. Experiments were performed on 30 male and 30 female adult Wistar rats weighing 200-220 gr. Pain sensitivity of animals was assessed 1 hour after a single intraperitoneal injection of the studied solution substances by acute pain tests (“tail-flick” test, Randall-Sellitto test, “hot plate” test). It was found out that EA+BTB, when injected once in doses of 5 and 50 mg/kg, significantly changes the pain sensitivity of male and female rats in acute pain tests, showing gender specificity of the analgesic effect with the participation of various pain mechanisms (spinal and supraspinal) and nociception components (perceptual and mechanical). The compound EA+BTB is recommended for further in-depth preclinical tests of its analgesic activity, decoding its physiological and molecular mechanisms in order to create an improved prototype of a new generation drug based on EA+BTB.

Interconnected conductive gel binder for high capacity silicon anode for Li-ion batteries

A new design for conjugation and crosslinking combined with a conjugated polymer and its application for high capacity Li-ion battery are demonstrated. Polyfluorene (PF), poly(phenylene) (PP), with lateral substituents, namely carboxylic acids, as a potential building block for conjugation was synthesized and characterized. The synthesis was achieved through Suzuki polycondensation reaction in the presence of Pd(PPh3)4 catalyst by using dibromo benzoic acid in conjunction with dioctylfluorene-diboronic acid bis(1,3-propanediol) ester. Thermal chemical cross-linking between carboxylic acid in the polymer backbone and free hydroxyl groups in poly(vinyl alcohol) (PVA) has been performed in the presence of Si. This approach enables a polymer binder with multi-functionality providing a high electronic conductivity and good cycling stability. Overall, we report on a Si-anode with capacity of 1932 mAh/g at C/3, demonstrating the improvement of the electrode using gel polymer binder.

Biotransformation of Tris(2-chloroethyl) Phosphate (TCEP) in Sediment Microcosms and the Adaptation of Microbial Communities to TCEP

Tris(2-chloroethyl) phosphate (TCEP), a typical chlorinated organophosphate ester (OPE), is an emerging contaminant of global concern because of its frequent occurrence, potential toxic effects, and persistence in the environment. In this study, we investigated the microbial TCEP biotransformation and the development of microbial communities in sediment microcosms with repeated TCEP amendments. The TCEP degradation fitted pseudo-zero-order kinetics, with reaction rates of 0.068 mg/(L h) after the first spike of 5 mg/L and 1.85 mg/(L h) after the second spike of 50 mg/L. TCEP was mainly degraded via phosphoester bond hydrolysis, evidenced by the production of bis(2-chloroethyl) phosphate (BCEP) and mono-chloroethyl phosphate (MCEP). Bis(2-chloroethyl) 2-hydroxyethyl phosphate (TCEP-OH), phosphoric bis(2-chloroethyl) (2-oxoethyl) ester (TCEP-CHO), phosphoric acid bis(2-chloroethyl)(carboxymethyl) ester (TCEP-COOH), and 2-chloroethyl 2-hydroxyethyl hydrogen phosphate (BCEP-OH) were also identified as microbial TCEP transformation products, indicating that TCEP degradation may follow hydrolytic dechlorination and oxidation pathways. Microbial community compositions in TCEP-amended microcosms shifted away from control microcosms after the second TCEP spike. Burkholderiales and Rhizobiales were two prevalent bacterial guilds enriched in TCEP-amended microcosms and were linked to the higher abundances of alkaline and acid phosphatase genes and genes involved in the metabolism of 2-chloroethanol, a side product of TCEP hydrolysis, indicating their importance in degrading TCEP and its metabolites.

Distribution and risk assessment of phthalates in water and sediment of the Pearl River Delta.

Phthalate esters (PAEs) are widely used industrial raw materials that are well known for their environmental contamination and toxicological effects as "endocrine disruptors." In this study, environmental levels of PAEs and eco-toxicological risk assessments were determined in the eight estuaries of the Pearl River (Estuaries), main upstream tributary (Xijiang River), urban river network (River network), and nature reserve reservoir (Reservoirs). Water and sediment samples from the above water systems were collected during the low-water period (May) and the high-water period (August) between 2012 and 2014. Solid phase and ultrasonic methods were used to extract 14 different PAEs that were analyzed by gas chromatography. The analytical average recovery of PAEs in water and sediment was 75.4% ± 4.9% and 121.5% ± 8.9%, respectively. The results showed that PAEs were detected in all of the samples, and the di-n-butyl phtalate (DBP) and benzyl butyl phthalate (BBP) monomers had a detection rate of 100% in water. Similarly, in sediment samples, the detection rates of diisobutyl phthalate (DiBP), DBP, dimethoxyethyl phthalate (DMEP), BBP, di-n-octyl phthalate (DnOP), and DNP ranged from 66.7 to 100%. Among these, in sediment samples, di(2-ethylhexyl) phthalate (DEHP) and phthalic acid bis(2-butoxyethyl) ester (DBEP) had detection rates of 95.8% to 100% in the Estuaries, Xijiang River, and River network. The concentrations of Σ14PAEs in water samples and sediments ranged from 12.95 ± 1.97 to 6717.29 ± 112.37 ng/L and 71.99 ± 8.72 to 17,340.04 ± 227.83 ng/g-dw, respectively. During the low-water period, the average concentration of Σ14PAEs in water and sediment was 1159.58 ± 97.22 ng/L and 2842.50 ± 178.21 ng/g-dw, respectively, and during the high-water period, 822.83 ± 53.19 ng/L and 1936.42 ± 111.31 ng/g-dw, respectively. In water, the average concentration of Σ14PAEs in 2013 and 2014 was 963.39 ± 19.55 ng/L and 2815.35 ± 176.32 ng/L, respectively. In sediment, the average concentrations of Σ14PAEs in 2012 to 2014 were 990.10 ± 23.33 ng/g-dw, 1084.20 ± 112.12 ng/g-dw, and 1816.89 ± 79.97 ng/g-dw, respectively, with concentrations showing an increasing trend year after year (2014 > 2013 > 2012). Potential risk assessment of water ecological, the results show that exceeding environmental risk level (ERL) value in higher molecular weight plasticizer (DEHP, DMEP, DNOP, DNP) was mainly distributed in water, the lower molecular weight plasticizer (BMP, DiBP) was mainly distributed in sediment.

Recovery of yttrium and europium from spent fluorescent lamps using pure levulinic acid and the deep eutectic solvent levulinic acid-choline chloride.

A solvometallurgical approach for the recovery of rare-earth elements from lamp phosphor waste was developed. The solubility of individual phosphors in different deep-eutectic solvents (DESs) was measured. The DES levulinic acid–choline chloride (xChCl = 0.33) showed high solubility of the YOX phosphor (Y2O3:Eu3+) and low solubility of the HALO phosphor (Sr,Ca)10(PO4)(Cl,F)2:Sb3+,Mn2+, which does not contain any rare-earth element. This DES was selected for further investigation. When the DES was compared to pure levulinic acid, very similar leaching behaviour was observed, showing that the proton activity is more important than the chloride as a metal ligand. The leaching of YOX and HALO using levulinic acid–choline chloride (xChCl = 0.33) or pure levulinic acid was optimised in terms of water content, temperature and leaching time. The optimised parameters were validated in a synthetic mixture of phosphors and in real lamp phosphor waste. The co-dissolution of HALO is higher in the real waste than in the synthetic mixture. The real waste was also leached with an aqueous solution of hydrochloric acid, which was non-selective against dissolution of YOX, and with the functionalised ionic liquid betainium bis(trifluoromethylsulfonyl)imide. The ionic liquid gave a similar selectivity as levulinic acid, but is much more expensive. The recovery of the metals from the pregnant leach solution was tested via precipitation with oxalic acid and solvent extraction. Oxalic acid precipitation was not suitable for the DES system. The metals could be extracted via solvent extraction with the acidic extractant bis(2-ethylhexyl)phosphoric acid (D2EHPA) and stripped by an aqueous hydrochloric acid solution. Pure levulinic acid was found to be more suitable than the corresponding ChCl-based DES for the selective recovery of YOX.