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1.
Nat Commun ; 11(1): 4368, 2020 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-32868758

RESUMO

Increased extracellular sodium activates Th17 cells, which provide protection from bacterial and fungal infections. Whilst high salt diets have been shown to worsen autoimmune disease, the immunological consequences of clinical salt depletion are unknown. Here, we investigate immunity in patients with inherited salt-losing tubulopathies (SLT). Forty-seven genotyped SLT patients (with Bartter, Gitelman or EAST Syndromes) are recruited. Clinical features of dysregulated immunity are recorded with a standardised questionnaire and immunological investigations of IL-17 responsiveness undertaken. The effects of altering extracellular ionic concentrations on immune responses are then assessed. Patients are hypokalaemic and hypomagnesaemic, with reduced interstitial sodium stores determined by 23Na-magnetic resonance imaging. SLT patients report increased mucosal infections and allergic disease compared to age-matched controls. Aligned with their clinical phenotype, SLT patients have an increased ratio of Th2:Th17 cells. SLT Th17 and Tc17 polarisation is reduced in vitro, yet STAT1 and STAT3 phosphorylation and calcium flux following T cell activation are unaffected. In control cells, the addition of extracellular sodium (+40 mM), potassium (+2 mM), or magnesium (+1 mM) reduces Th2:Th17 ratio and augments Th17 polarisation. Our results thus show that the ionic environment typical in SLT impairs IL-17 immunity, but the intracellular pathways that mediate salt-driven Th17 polarisation are intact and in vitro IL-17 responses can be reinvigorated by increasing extracellular sodium concentration. Whether better correction of extracellular ions can rescue the immunophenotype in vivo in SLT patients remains unknown.


Assuntos
Síndromes de Imunodeficiência/etiologia , Interleucina-17/metabolismo , Túbulos Renais Distais/patologia , Adolescente , Adulto , Idoso de 80 Anos ou mais , Animais , Pré-Escolar , Doença Crônica , Estudos de Coortes , Feminino , Doenças Genéticas Inatas , Humanos , Magnésio/metabolismo , Masculino , Pessoa de Meia-Idade , Potássio/metabolismo , Sais/metabolismo , Sais/uso terapêutico , Sódio/metabolismo , Cloreto de Sódio/metabolismo , Cloreto de Sódio na Dieta/uso terapêutico , Células Th17/metabolismo , Células Th2/metabolismo , Adulto Jovem
2.
Aquat Toxicol ; 226: 105568, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32791376

RESUMO

An emerging Multi-Ion Toxicity (MIT) model for assessment of environmental salt pollution is based on the premise that major ion toxicity to aquatic organisms is related to a critical disturbance of the trans-epithelial potential across the gills (ΔTEP), which can be predicted by electrochemical theory. However, the model has never been evaluated physiologically. We directly tested key assumptions by examining the individual effects of eight different salts (NaCl, Na2SO4, MgCl2, MgSO4, KCl, K2SO4, CaCl2, and CaSO4) on measured TEP in three different fish species (fathead minnow, Pimephales promelas = FHM; channel catfish, Ictalurus punctatus = CC; bluegill, Lepomis macrochirus = BG). A geometric concentration series based on previously reported 96-h LC50 values for FHM was used. All salts caused concentration-dependent increases in TEP to less negative/more positive values in a pattern well-described by the Michaelis-Menten equation. The ΔTEP responses for different salts were similar to one another within each species when concentrations were expressed as a percentage of the FHM LC50. A plateau was reached at or before 100 % of the LC50 where the ΔTEP values were remarkably consistent, with only 1.4 to 2.2-fold variation. This relative uniformity in the ΔTEP responses contrasts with 28-fold variation in salt concentration (in mmol L-1), 9.6-fold in total dissolved solids, and 7.9-fold in conductivity at the LC50. The Michaelis-Menten Km values (salt concentrations causing 50 % of the ΔTEPmax) were positively related to the 96-h LC50 values. ΔTEP responses were not a direct effect of osmolarity in all species and were related to specific cation rather than specific anion concentrations in FHM. These responses were stable for up to 24 h in CC. The results provide strong physiological support for the assumptions of the MIT model, are coherent with electrochemical theory, and point to areas for future research.


Assuntos
Cyprinidae/fisiologia , Epitélio/fisiologia , Brânquias/efeitos dos fármacos , Potenciais da Membrana/efeitos dos fármacos , Perciformes/fisiologia , Sais/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Eletrodos , Brânquias/fisiologia , Concentração Osmolar
3.
J Chromatogr A ; 1626: 461381, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32797855

RESUMO

A reliable and sensitive analytical approach has been optimized for the extraction of seven polychlorinated biphenyls (PCBs) from human breast milk. Hollow fiber liquid phase microextraction (HF-LPME) was applied for the first time for the extraction and pre-concentration of the analytes. Analytes were separated by gas chromatography with electron capture detector (GC-µECD) for the sensitive detection and mass spectrometry for the unequivocal identification. A rotable central composite design (RCCD) was performed for the multivariate optimization of the method. The best results were obtained at 40 °C during 30 min and 600 rpm of stirring speed using a hollow fiber length of 5 cm and toluene as an extractant phase and salt addition was not required. The detection limits were in the range 7-14 ng L-1 for PCBs. The coefficients of determination of the calibration curves indicated good linearity (R2> 0.96) and the enrichment factors ranged from 74 to 143. This type of study is of great importance due to the deleterious effect that the presence of contaminants can produce in infants health related to the immature character of the defense system. Moreover, exclusive breastfeeding is recommended by neonatologists up to six months of life and as complementary food during the first two years.


Assuntos
Microextração em Fase Líquida/métodos , Leite Humano/química , Bifenilos Policlorados/análise , Cromatografia Gasosa , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Bifenilos Policlorados/isolamento & purificação , Porosidade , Reprodutibilidade dos Testes , Sais/química
4.
J Chromatogr A ; 1628: 461424, 2020 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-32822969

RESUMO

Block copolymers that exhibit both an upper critical solution temperature and a lower critical solution temperature are difficult to characterize due to inherent solubility difference between the two blocks. For example, accurate determination of both the molar mass and molar mass distribution is challenging for polyzwitterion-block-N-isopropyl acrylamide (NIPAM) copolymers in aqueous solutions due to self-assembly. However, there are a few examples of using size exclusion chromatography (SEC) for characterization, in which hexafluoro isopropanol (HFIP) is used in all cases. Yet, researchers are hesitant to use this solvent due to how expensive and hazardous HFIP is. Therefore, alternatives to HFIP for SEC analysis would be desirable. Here, a systematic methodology featuring aqueous SEC is demonstrated using several solvent conditions to enable the elution of polyzwitterion-block-NIPAM copolymers on Agilent PolarGel† and Tosoh TSKgel† column sets. These SEC conditions include 0.2 M KI in water on the PolarGel columns and 0.2 M KI/ 30% DMF in water on the PolarGel and TSKgel columns. These aqueous systems can be utilized for the characterization of similar water-soluble block copolymers that are relevant for drug delivery and other biomedical applications.


Assuntos
Acrilamidas/química , Cromatografia em Gel/métodos , Polímeros/química , Acrilamidas/síntese química , Polimerização , Polímeros/síntese química , Sais/química , Solventes/química , Ácidos Sulfônicos/síntese química , Ácidos Sulfônicos/química , Temperatura , Água
5.
J Chromatogr A ; 1628: 461429, 2020 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-32822971

RESUMO

Recent studies have shown that by combining orthogonal, non-affinity chromatography steps, it is possible to rapidly develop efficient purification processes for molecules of interest. Here, we build upon previous work to develop a flexible framework for identifying resins that remove optimally orthogonal sets of impurities for a wide variety of products. Our approach involves screening a library of proteins with diverse properties (pI ranging from 5.0-11.4 and varying hydrophobicity measured by retention in a HIC gradient) on a library of resins and quantifying each resin's ability to separate every protein pair in the library. Orthogonality is then defined as the degree to which two resins separate mutually exclusive sets of protein pairs. We applied this approach to a library of model proteins and a series of strong, salt tolerant, and multimodal ion exchangers and evaluated which resin combinations performed well and which performed poorly. In particular, we found that strong cation and strong anion exchangers were orthogonal, while strong and salt tolerant anion exchangers were not orthogonal. Interestingly, salt tolerant and multimodal cation exchangers were found to be orthogonal and the best resin combination included a multimodal cation exchange resin and a tentacular anion exchange resin. This approach for quantifying orthogonality is valuable in that it can be used both as a criteria for resin design as well as process design. We envision that, using this framework, it will be possible to design a set of next generation chromatography ligands that are explicitly engineered to optimize separability and orthogonality.


Assuntos
Resinas de Troca de Ânions/química , Resinas de Troca de Cátion/química , Cromatografia por Troca Iônica/métodos , Animais , Bovinos , Galinhas , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Ligantes , Proteínas/análise , Proteínas/química , Sais/química , Suínos
6.
J Chromatogr A ; 1626: 461351, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32797831

RESUMO

Traditional polymer-separation methods, such as size-exclusion chromatography and (gradient) liquid adsorption chromatography, cannot provide separations exclusively based on the number of deprotonated carboxylic-acid groups along the backbone chain of polymers. A novel separation method, based on non-aqueous ion-exchange chromatography (NAIEX), was developed, which allows such a separation of acid-functional polymers that are soluble in organic solvents. The polar, aprotic N-methyl-2-pyrrolidone was found to be a suitable solvent. It features a high relative permittivity (favouring dissociation of ion pairs into free ions) and it is a good solvent for polymers and organic salts, such as triethyl-ammonium formate. A negative charge is established on these polymers by deprotonation of the carboxylic-acid groups in the presence of an organic superbase (tetramethyl guanidine). Traditional potent organic bases, such as triethylamine, do not possess the base strength to compensate for the increase in pKa of polymeric carboxylic acid groups in non-aqueous conditions. Triethyl-ammonium formate is proposed as an alternative to traditional salts used for elution in aqueous ion-exchange chromatography. Separation was performed on an industry-standard strong-anion-exchange column and (near-)universal detection of the polymers was performed by high-temperature evaporative-light-scattering detection. The NAIEX method yielded a separation based on the acid-functionality distribution of the polymer. NAIEX was compared with traditional normal- and reversed-phase liquid-chromatography approaches for the separation of acid-functional copolymers.


Assuntos
Cromatografia por Troca Iônica/métodos , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Polímeros/química , Espectroscopia de Prótons por Ressonância Magnética , Sais/química , Solventes/química
7.
J Chromatogr A ; 1626: 461324, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32797817

RESUMO

Sorption of PFASs onto surfaces of laboratory materials has been frequently reported. Due to the often complex and poorly understood nature of such sorption, workarounds have often included use of whole samples only, accompanied by sample vessel rinsing to desorb active surfaces. The resulting methods tend to require considerable sample preparation times and preclude typical activities such as aliquoting and dilution of water samples prior to extraction. This manuscript reports an approach for PFAS analysis which uses subsampling of water matrices from vessels including centrifuge tubes and autosampler vials, through the optimized use of solvent to reduce PFAS retention on subsampling vessels. Online solid phase extraction (SPE) using a weak anion exchange resin is then used to concentrate sample aliquots to improve sensitivity and allow for removal of matrix interferences. With the technique of ultra performance liquid chromatography (UPLC) coupled to isotope dilution tandem mass spectrometry, statistically based quantitation limits ranged from sub ng/L to single digit ng/L for carboxylate, sulfonate, and sulfonamide PFASs analytes from C4 to C12. Linear calibration ranges were from 0.25 to 4000 ng/L. Matrix effects relevant for drinking water treatment studies, such as cations, organic carbon, and competing PFAS compounds, were evaluated and found to not impact method performance within QC criteria consistent with study data quality objectives.


Assuntos
Fluorcarbonetos/análise , Indicadores e Reagentes/análise , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão , Fluorcarbonetos/isolamento & purificação , Água Doce/análise , Indicadores e Reagentes/isolamento & purificação , Marcação por Isótopo , Sais/química , Extração em Fase Sólida , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/isolamento & purificação
8.
PLoS One ; 15(8): e0237884, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32841243

RESUMO

The Solanum tuberosum plant specific insert (StPSI) has a defensive role in potato plants, with the requirements of acidic pH and anionic lipids. The StPSI contains a set of three highly conserved disulfide bonds that bridge the protein's helical domains. Removal of these bonds leads to enhanced membrane interactions. This work examined the effects of their sequential removal, both individually and in combination, using all-atom molecular dynamics to elucidate the role of disulfide linkages in maintaining overall protein tertiary structure. The tertiary structure was found to remain stable at both acidic (active) and neutral (inactive) pH despite the removal of disulfide linkages. The findings include how the dimer structure is stabilized and the impact on secondary structure on a residue-basis as a function of disulfide bond removal. The StPSI possesses an extensive network of inter-monomer hydrophobic interactions and intra-monomer hydrogen bonds, which is likely the key to the stability of the StPSI by stabilizing local secondary structure and the tertiary saposin-fold, leading to a robust association between monomers, regardless of the disulfide bond state. Removal of disulfide bonds did not significantly impact secondary structure, nor lead to quaternary structural changes. Instead, disulfide bond removal induces regions of amino acids with relatively higher or lower variation in secondary structure, relative to when all the disulfide bonds are intact. Although disulfide bonds are not required to preserve overall secondary structure, they may have an important role in maintaining a less plastic structure within plant cells in order to regulate membrane affinity or targeting.


Assuntos
Dissulfetos/metabolismo , Simulação de Dinâmica Molecular , Proteínas de Plantas/metabolismo , Saposinas/metabolismo , Solanum tuberosum/metabolismo , Cisteína/metabolismo , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Proteínas de Plantas/química , Multimerização Proteica , Estabilidade Proteica , Estrutura Secundária de Proteína , Sais/química , Enxofre/metabolismo
9.
Acta Crystallogr C Struct Chem ; 76(Pt 8): 746-752, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32756037

RESUMO

A series of five binary complexes, i.e. three cocrystals and two molecular salts, using 2-chloro-4-nitrobenzoic acid as a coformer have been produced with five commonly available compounds, some of pharmaceutical relevance, namely, 2-chloro-4-nitrobenzoic acid-isonicotinamide (1/1), C7H4ClNO4·C6H6N2O, 2-chloro-4-nitrobenzoic acid-3,3-diethylpyridine-2,4(1H,3H)-dione (2/1), 2C7H4ClNO4·C9H13NO2, 2-chloro-4-nitrobenzoic acid-pyrrolidin-2-one (1/1), C7H4ClNO4·C4H7NO, 2-carboxypiperidinium 2-chloro-4-nitrobenzoate, C6H12NO2-·C7H3ClNO4-, and (2-hydroxyethyl)ammonium 2-chloro-4-nitrobenzoate, C2H8NO+·C7H3ClNO4-. The coformer falls under the classification of a `generally regarded as safe' compound. All five complexes make use of a number of different heteromeric hydrogen-bonded interactions. Intermolecular potentials were evaluated using the CSD-Materials module.


Assuntos
Clorobenzoatos/química , Sais/química , Cristalografia por Raios X , Preparações Farmacêuticas
10.
Food Chem ; 333: 127493, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32659659

RESUMO

The effects of the addition of salt ions and molecular weights (Mw) of CH on Mesona chinensis polysaccharide (MCP)-chitosan (CH) hydrogel were investigated. Result indicated both low concentration of monovalent salt ions (Na+ and K+), divalent cations (Ca2+) and oxoanions (SO42-) could promote the gel properties of MCP-CH hydrogel. The Mw of CH has huge impact on the formation and properties of hydrogel. Combining the relationship between rheology and structural, monovalent salt ions such as Na+ and K+ affect gel formation and its properties by influencing electrostatic interaction and chain conformation. Both divalent cations (Ca2+) and oxoanions (SO42-) facilitated the formation of gel networks via electrostatic interaction, coordination bonds and hydrogen bonds. Moreover, Mw of CH influenced formation and texture of MCP-CH hydrogel via affecting the conformation of CH molecular chain. These findings will provide a few theoretical bases to understand the formation mechanism of MCP-CH hydrogel.


Assuntos
Quitosana/química , Hidrogéis/química , Lamiaceae/química , Extratos Vegetais/química , Polieletrólitos/química , Sais/química , Ânions/química , Cálcio/química , Hidrogéis/síntese química , Peso Molecular , Polissacarídeos/química , Potássio/química , Reologia , Sódio/química
11.
Chemosphere ; 260: 127623, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32668363

RESUMO

The global demand of lithium is rising steadily, and many industrially advanced countries may find it hard to secure an uninterrupted supply of lithium for meeting their manufacturing demands. Thus, innovative processes for lithium recovery from a wide range of natural reserves should be explored for meeting the future demands. In this study, a novel integrated approach was investigated by combining nanofiltration (NF), membrane distillation (MD) and precipitation processes for lithium recovery from salt-lake brines. Initially, the brine was filtered with an NF membrane for the separation of lithium ions (Li+) from competing ions such as Na+, K+, Ca2+ and Mg2+. The extent of permeation of metal ions by the NF membrane was governed by their hydrated ionic radii. Rejection by NF membrane was 42% for Li, 48% for Na and 61% for K, while both the divalent cations were effectively rejected (above 90%). Importantly, in the NF-permeate, Mg2+/Li+ mass ratio reduced to less than 6 (suggested for lithium recovery). The result showed that MD can enrich lithium with a concentration of 2.5 for raw brine and 5 for NF-treated brine. Following the enrichment of NF-permeate by the MD membrane, a two-stage precipitation method was used for the recovery of lithium. X-ray diffraction confirmed the precipitation of lithium as well as the formation of lithium carbonate crystals.


Assuntos
Lagos/química , Lítio/análise , Poluentes Químicos da Água/análise , Cátions Bivalentes , Destilação , Íons , Lítio/química , Sais , Sódio , Cloreto de Sódio , Poluentes Químicos da Água/química
12.
J Chromatogr A ; 1625: 461305, 2020 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-32709348

RESUMO

A novel kind of magnetic porous carbon nano-fibers (Fe3O4@P-CNFs) materials was successfully prepared and used as an adsorbent. Based on the above-mentioned adsorbent, a simple and effective magnetic disperse solid-phase extraction (MSPE) method was developed and first utilized to the enrichment and purification of five Sudan dyes (including Sudan I, Sudan II, Sudan III, Sudan IV, and Sudan Red 7B) in foodstuffs for the first time. High-performance liquid chromatography was used to determine the content of the Sudan dyes. The parameters affecting the extraction performance were studied and optimized, including the amount of the adsorbent and inorganic salt, type and the volume of the eluent, pH of the sample solution and extraction time. Under the optimized experimental conditions, the results show that the proposed method has a good linear relationship (r≥ 0.9993). The limits of detection range from 0.88 µg L-1 to 1.27 µg L-1. The recoveries range from 86.6% to 99.7% with the relative standard deviations ranging from 0.6% to 7.9% in the methodology validation. The above-mentioned results indicate that the proposed method is a sensitive and reliable procedure with good reproducibility for the detection of Sudan dyes residues in foodstuffs.


Assuntos
Compostos Azo/análise , Fibra de Carbono/química , Corantes/análise , Análise de Alimentos , Fenômenos Magnéticos , Nanofibras/química , Adsorção , Compostos Azo/química , Corantes/química , Concentração de Íons de Hidrogênio , Limite de Detecção , Nanofibras/ultraestrutura , Porosidade , Análise de Regressão , Reprodutibilidade dos Testes , Sais/química , Fatores de Tempo
13.
J Environ Sci (China) ; 95: 65-72, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32653194

RESUMO

Mineral dust, soil, and sea salt aerosols are among the most abundant primary inorganic aerosols in the atmosphere, and their hygroscopicity affects the hydrological cycle and global climate. We investigated the hygroscopic behaviors of six Na- and K-containing salts commonly found in those primary organic aerosols. Their hygroscopic growths as a function of relative humidity (RH) agree well with thermodynamic model prediction. Temperature dependence of deliquescence RH (DRH) values for five of those salts was also investigated, which are comparable to those in literature within 1%-2% RH, most showing negative dependence on temperature. Hygroscopic growth curves of real-world soil and sea salt samples were also measured. The hygroscopic growths of two more-hydroscopic saline soil samples and of sea salt can be predicted by the thermodynamic model based on the measured water-soluble ionic composition. The substantial amounts of water-soluble ions, including Na+ and K+, in saline soil samples imply that even nascent saline soil samples are quite hygroscopic at high-RH (>80%) conditions. For three less-hygroscopic dust samples, however, measurements showed higher water uptake ability than that predicted by the thermodynamic model. The small amount of water taken up by less-hygroscopic dust samples suggests that dust particles might contain thin layers of water even to very low RH. The results of this study provide a comprehensive characterization of the hygroscopicity of Na- and K-containing salts as related to their roles in the hygroscopic behaviors of saline mineral dusts and sea salt aerosols.


Assuntos
Poluentes Atmosféricos/análise , Poeira , Aerossóis/análise , Minerais , Potássio , Sais , Sódio , Molhabilidade
14.
Environ Sci Process Impacts ; 22(8): 1759-1767, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32697206

RESUMO

Magnesium and calcium chloride salts contribute to the global atmospheric aerosol burden via emission of sea spray and mineral dust. Their influence on aerosol hygroscopicity and cloud forming potential is important but uncertain with ambiguities between results reported in the literature. To address this, we have conducted measurements of the hygroscopic growth and critical supersaturation of dried, size selected nano-particles made from aqueous solution droplets of MgCl2 and CaCl2, respectively, and compare experimentally derived values with results from state-of-the-art thermodynamic modelling. It is characteristic of both MgCl2 and CaCl2 salts that they bind water in the form of hydrates under a range of ambient conditions. We discuss how hydrate formation affects the particles' water uptake and provide an expression for hydrate correction factors needed in calculations of hygroscopic growth factors, critical super-saturations, and derived κ values of particles containing hydrate forming salts. We demonstrate the importance of accounting for hydrate forming salts when predicting hygroscopic properties of sea spray aerosol.


Assuntos
Sais , Água , Aerossóis , Poeira , Molhabilidade
15.
Medicine (Baltimore) ; 99(29): e20186, 2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-32702808

RESUMO

It has been well established that dietary patterns play important roles in the pathogenesis and development of hypertension. Our aim was to investigate the association between pregnancy dietary patterns and the risk of hypertension among nulliparous pregnant Chinese women.A cross-sectional, case-control study.Three hospitals in Haikou, the capital of Hainan Province, South China.A total of 2580 participants who reported dietary intake using a validated food frequency questionnaire (FFQ).Four primary dietary patterns were identified by principal component factor analysis and labeled as traditional Chinese, animal food, Western food, and salty snacks patterns. Women with high scores on pattern characterized by salty snacks were at increased risk.This study suggests that dietary pattern characterized by salty snack increases the risk of hypertension during pregnancy.


Assuntos
Dieta Ocidental/efeitos adversos , Dieta/efeitos adversos , Hipertensão Induzida pela Gravidez/epidemiologia , Sais/efeitos adversos , Adulto , Estudos de Casos e Controles , China/epidemiologia , Estudos Transversais , Dieta/tendências , Ingestão de Alimentos/psicologia , Comportamento Alimentar/psicologia , Feminino , Humanos , Hipertensão Induzida pela Gravidez/etiologia , Incidência , Paridade/fisiologia , Gravidez , Inquéritos e Questionários
16.
Water Res ; 183: 116059, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32721705

RESUMO

Thermal-based Zero Liquid Discharge (ZLD) process has been used for managing industrial brine. However, conventional thermal ZLD process is very energy intensive. In view of this, pre-concentration techniques have been applied prior to thermal process to reduce energy consumption of ZLD systems. Capacitive Deionization (CDI) is an emerging desalination technique and has yet to be extensively explored for the treatment of industrial brine especially for ZLD applications. High concentration of total dissolved solids (TDS) and high fouling potential of industrial brine are two major challenges in CDI process. This paper reviews the possible factors for optimizing CDI process in industrial brine treatment, namely, cell architectures, strategies in operation and fouling control. Cell architectures of membrane CDI (MCDI) and flow-electrode CDI (CDI) are preferred options for treating industrial brine compared with classic CDI in terms of energy consumption and fouling propensity. There are other operational strategies that could enhance the feasibility of using CDI process for ZLD application. These include reversed voltage desorption, multi-stage operation, brine recirculation and fouling control. Fouling control methods comprise pretreatment, antifouling modification, antiscalant and chemical cleaning. These methods could be integrated to optimize fouling mitigation. In addition to providing insights on feasibility of using CDI to concentrate industrial brines, this review also proposed guidelines for optimizing CDI process applied to treat industrial brines for ZLD applications.


Assuntos
Purificação da Água , Eletrodos , Sais
17.
Food Chem ; 332: 127371, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32622188

RESUMO

A simple and sensitive salting out-assisted dispersive liquid-liquid microextraction method using deep eutectic solvent combined with back extraction and micellar electrokinetic capillary chromatography (SO-DLLME-DES-BE-MECC) was developed for the determination of fluoroquinolones in milk, honey and water samples. Several parameters affecting the extraction efficiency including DES volume, vortex time, centrifugation time, salt type and amount, sample pH and volume, etc. were investigated. Good linearity were obtained for fluoroquinolones in a range of 0.020-3.200 µg mL-1 and 0.030-4.800 µg mL-1 with LODs less than 0.010 µg mL-1. The recoveries were in the ranges of 95.0-104.9%, 90.1-110.2% and 87.8-114.1% for water, honey and milk samples, respectively. The relative standard deviations for reproducibility were all below 7.6%. Under the optimized conditions, the enrichment factors for analytes were achieved in the range from 531 to 858 folds. The presented method was successfully applied for the determination of fluoroquinolones in milk, honey and water samples.


Assuntos
Cromatografia Capilar Eletrocinética Micelar , Fluoroquinolonas/análise , Mel/análise , Microextração em Fase Líquida/métodos , Leite/química , Solventes/química , Água/química , Animais , Fluoroquinolonas/química , Fluoroquinolonas/isolamento & purificação , Limite de Detecção , Sais/química
18.
Environ Sci Pollut Res Int ; 27(27): 34388-34397, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32557047

RESUMO

Increasing knowledge of nitrate removal using denitrifying bioreactors has illustrated the usefulness of this management practice for treating discharge water from agricultural land uses. The objective of this study was to assess the viability of almond shell, chopped carob, olive bone, and citrus woodchip as carbon media for denitrification of brine with high nitrate load (EC ≈ 20 dS m-1, NO3--N concentration ≈ 65-80 mg NO3--N L-1) in bioreactors. To the authors' knowledge, this is the first test of denitrifying brine using organic wastes as the carbon substrate, and the first use of these carbon media for that purpose. Nitrate removal efficiency and efficiency:cost ratio were considered. The results indicated that the best removal efficiency and cheapest cost were provided by citrus woodchip (3.02 ± 0.15 mg NO3--N m-3 d-1) at a cost of ≈ 6€ m-3, followed by almond shell (1.54 ± 0.20 mg NO3--N m-3 d-1) at a cost of ≈ 19€ m-3. Chopped carob and olive bone showed negligible nitrate removal in the brine; chopped carob generated acidic leachate with extremely high dissolved organic carbon, and olive bone resulted in a highly saline leachate. Of the four media tested, the results of this study indicated that citrus woodchip was the most suitable media for denitrification of the brine.


Assuntos
Desnitrificação , Água Subterrânea , Reatores Biológicos , Nitratos , Sais , Espanha
19.
Chemosphere ; 257: 127214, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32505039

RESUMO

Reverse Osmosis (RO) desalination is an important step of wastewater reuse as it can remove salts and trace contaminants. However, RO also generates high salinity brines that need to be dealt with. Membrane distillation (MD), a process largely unaffected by salinity, provides a way to treat desalination brines up to high water recovery and has been proposed as a solution for RO brine management. However, pore wetting of membranes in MD is one of the major hurdles that prevents its implementation in wastewater treatment systems, as amphiphilic organic compounds present in wastewater can lead to pore wetting and loss of selectivity over time. The objective of this study was to identify a pre-treatment strategy to prevent wetting in MD treatment of municipal wastewater RO brines. We compared three pre-treatments with different separation or removal mechanisms: foam fractionation, advanced oxidation, and ultrafiltration. We evaluated membrane wetting by measuring the change in conductivity in the distillate and identified the most effective pre-treatment to prevent wetting in MD. The results show that wetting is prevented by pre-treating the brine with foam fractionation. The effectiveness of foam fractionation as a wetting control strategy was confirmed for a high wetting propensity synthetic water using sodium dodecyl sulfate as a model wetting compound. Finally, the effect of the pre-treatments on the desalination brine was evaluated to understand the nature of the compounds removed by each treatment. The results of this study will help implement MD as a treatment process for desalination brines in municipal wastewater reuse systems.


Assuntos
Eliminação de Resíduos Líquidos/métodos , Destilação , Membranas Artificiais , Osmose , Oxirredução , Salinidade , Sais , Águas Residuárias , Água , Purificação da Água/métodos , Molhabilidade
20.
Bioresour Technol ; 313: 123641, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32535522

RESUMO

The metal(loid)-enriched Avicennia marina biomass obtained from phytoremediation was impregnated with two ferric salts (FeCl3 and Fe(NO3)3) prior to pyrolysis at 300-700 °C, aiming to study the influence on pyrolytic product properties and heavy metal(loid) deportment. Results showed that the impregnated ferric salts increased the fixed carbon content of biochars, hydrocarbon fractions in bio-oils, and the evolution of CO and H2 in gases. Cd in biomass could be effectively removed from the biomass by FeCl3 impregnation. During pyrolysis, the ferric salts enhanced the elemental recovery of As, Cr, Ni and Pb in the biochars and decreased their distribution in gases. Notably, the ferric salt pre-treatment inhibited the mobility and bio-availability of most elements in the biochars. This study indicated that ferric salt impregnation catalysed the pyrolysis process of metal(loid) contaminated biomass, enabled the operation temperature at 500-700 °C with minimal environmental risks, providing a safe and value-added way to the phytoremediation-pyrolysis scheme.


Assuntos
Metais Pesados , Pirólise , Biomassa , Carvão Vegetal , Sais
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