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1.
Chemosphere ; 355: 141834, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38565376

RESUMEN

Membrane fouling caused by the organics-coated particles was the main obstacle for the highly efficient shale gas produced water (SGPW) treatment and recycling. In this study, a novel hybrid electrocoagulation (EC) and E-peroxone process coupled with UF (ECP-UF) process was proposed to examine the efficacy and elucidate the mechanism for UF fouling mitigation in assisting SGPW reuse. Compared to the TMP (transmembrane pressure) increase of -15 kPa in the EC-UF process, TMP in ECP-UF system marginally increased to -1.4 kPa for 3 filtration cycles under the current density of 15 mA/cm2. Both the total fouling index and hydraulically irreversible fouling index of the ECP-UF process were significantly lower than those of EC-UF process. According to the extended Derjaguin-Landau-Verwey-Overbeek theory, the potential barriers was the highest for ECP-UF processes due to the substantial increase of the acid-base interaction energy in ECP-UF process, which was well consistent with the TMP and SEM results. Turbidity and TOC of ECP-UF process were 63.6% and 45.8% lower than those of EC-UF process, respectively. According to the MW distribution, the variations of compounds and their relative contents were probably due to the oxidation and decomposing products of the macromolecular organics. The number of aromatic compound decreased, while the number of open-chain compounds (i.e., alkenes, alkanes and alcohols) increased in the permeate of ECP-UF process. Notably, the substantial decrease in the relative abundance of di-phthalate compounds was attributed to the high reactivity of these compounds with ·OH. Mechanism study indicated that ECP could realize the simultaneous coagulation, H2O2 generation and activation by O3, facilitating the enhancement of ·OH and Alb production and therefore beneficial for the improved water quality and UF fouling mitigation. Therefore, the ECP-UF process emerges as a high-efficient and space-saving approach, yielding a synergistic effect in mitigating UF fouling for SGPW recycling.


Asunto(s)
Ultrafiltración , Purificación del Agua , Gas Natural , Peróxido de Hidrógeno , Membranas Artificiales , Purificación del Agua/métodos , Electrocoagulación
2.
BMC Pulm Med ; 23(1): 253, 2023 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-37430308

RESUMEN

BACKGROUND: The role of echocardiography in the diagnostic and prognostic assessment of pulmonary hypertension (PH) has been widely studied recently. However, these findings have not undergone normative evaluation and may provide confusing evidence for clinicians. To evaluate and summarize existing evidence, we performed an umbrella review. METHODS: Systematic reviews and meta-analyses were searched in PubMed, Embase, Web of Science, and Cochrane Library from inception to September 4, 2022. The methodological quality of the included studies was assessed using Assessment of Multiple Systematic Reviews (AMSTAR), and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was used to evaluate the quality of evidence. RESULTS: Thirteen meta-analyses (nine diagnostic and four prognostic studies) were included after searching four databases. The methodological quality of the included studies was rated as high (62%) or moderate (38%) by AMSTAR. The thirteen included meta-analyses involved a total of 28 outcome measures. The quality of evidence for these outcomes were high (7%), moderate (29%), low (39%), and very low (25%) using GRADE methodology. In the detection of PH, the sensitivity of systolic pulmonary arterial pressure is 0.85-0.88, and the sensitivity and specificity of right ventricular outflow tract acceleration time are 0.84. Pericardial effusion, right atrial area, and tricuspid annulus systolic displacement provide prognostic value in patients with pulmonary arterial hypertension with hazard ratios between 1.45 and 1.70. Meanwhile, right ventricular longitudinal strain has independent prognostic value in patients with PH, with a hazard ratio of 2.96-3.67. CONCLUSION: The umbrella review recommends echocardiography for PH detection and prognosis. Systolic pulmonary arterial pressure and right ventricular outflow tract acceleration time can be utilized for detection, while several factors including pericardial effusion, right atrial area, tricuspid annular systolic displacement, and right ventricular longitudinal strain have demonstrated prognostic significance. TRIAL REGISTRATION: PROSPERO (CRD42022356091), https://www.crd.york.ac.uk/prospero/ .


Asunto(s)
Fibrilación Atrial , Hipertensión Pulmonar , Derrame Pericárdico , Humanos , Ecocardiografía , Hipertensión Pulmonar/diagnóstico por imagen , Pronóstico , Revisiones Sistemáticas como Asunto , Metaanálisis como Asunto
5.
ACS Appl Mater Interfaces ; 13(18): 21379-21389, 2021 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-33914506

RESUMEN

The rational design of continuous covalent organic framework (COF)-based membranes is challenging for desalination applications, mainly due to the larger intrinsic pore size of COFs and defects in the crystalline film, which lead to a negligible NaCl rejection ratio. In this work, we first demonstrated a COF-based desalination membrane with in situ cross-linking of a COF-TpPa layer by trimesoyl chloride (TMC) to stitch the defects between COF crystals and cross-link the COF cavity with high-cross-linking degree networks to enhance NaCl rejection. With the addition of TMC monomers, both small spherical nodules and some elongated "leaf-like" features were observed on the membrane surface due to the appearance of nanovoids during cross-linking. The resulting COF-based desalination membrane had a water permeability of approximately 0.81 L m-2 h-1 bar-1 and offered substantial enhancement of the NaCl rejection ratio from being negligible to 93.3% at 5 bar. Mechanistic analysis indicated that the amidation reaction of the secondary amine in keto COF with TMC induced the formation of a highly porous network structure both in the cavity and on the exterior of COF, thereby successfully forming a continuous and nanovoid-containing selective layer for desalination. In addition, the membrane exhibited excellent desalting performance for real industrial wastewater with both low and high salinity. This study proposed that the introduction of a cross-linker to react with the terminal amine group and secondary amine in the backbone of the keto form of COF or its derivatives could provide a facile and scalable approach to fabricate a COF-based membrane with superior NaCl rejection. This opens a new fabrication route for COF-based desalination membranes, as well as extended applications in water desalination.

6.
Chemosphere ; 262: 127968, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33182104

RESUMEN

Electrocoagulation (EC) coupled with E-peroxone process (ECP) was a promising and cost-effective integrated technology for shale gas fracturing flowback water (SGFFW) treatment. In this study, the ECP process was comprehensively compared with two sequential processes (EC followed by E-peroxone (EC-E-peroxone) and E-peroxone followed by EC (E-peroxone-EC)) to elucidate the synergistic effect of this coupled process. In EC-E-peroxone process, COD decreased by 89.2%, while COD decreased by 82.5% for 180 min in E-peroxone-EC process. However, COD removal efficiency was 82.4% in ECP for only 90 min. Average current efficiency of the ECP process was 29.9%, which was twice than that of the sequential processes. The enhancement factor was calculated to be 1.63, demonstrating the substantial significant synergistic effects for ECP. Only low MW components could be observed for the EC-E-peroxone (average MW = 533 Da with PD ≈ 1) and ECP process (MW = 538 Da with PD ≈ 1). These results suggested that EC-E-peroxone and ECP process had much stronger oxidation ability, demonstrating the enhancement of OH production induced by the Al-based coagulants might be responsible for the significant enhancement of COD removal. These results indicated there could be a synergistic effect between EC and ozone in addition to EC and E-peroxone reactions. Compared to the two sequential processes, ECP was a high efficiency and space-saving electrochemical system with simultaneous coagulation and enhanced OH generation by the products of anode and the cathode.


Asunto(s)
Técnicas Electroquímicas/métodos , Peróxido de Hidrógeno/química , Gas Natural/análisis , Ozono/química , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Análisis de la Demanda Biológica de Oxígeno , China , Electrodos , Floculación , Fracking Hidráulico , Oxidación-Reducción , Aguas Residuales/química
7.
Chemosphere ; 244: 125386, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32050321

RESUMEN

Polysulfone ultrafiltration (UF) and polypiperazine-amide nanofiltration (NF) membranes were first fabricated by phase inversion and interfacial polymerization, and then modified by the commonly used TiO2 on the membrane surface, respectively. Compared with the pristine UF and NF membranes, pure water flux decreased by 40.66% for modified UF membrane and 12.92% for modified NF membrane, while the contact angle of the modified membranes decreased from 66.5° to 35.3° for UF membrane and from 48.2° to37.7° for NF membrane. However, the membrane modified by TiO2 nanoparticles for both UF and NF membranes exhibited much better anti-fouling and separation performance for two types of oil-in-water emulsions with different droplet size (i.e., prepared oil-in-water emulsion with low salinity and oil produced water in Shengli oilfield, China). It was obvious that water flux of modified UF only slightly decreased and the stable water flux was 2.2 times and 15.6% higher than that of pristine membranes for the prepared oil-in-water emulsion and produced water, respectively. According to the five fouling models for UF, the TiO2 modified UF membrane could alleviate the fouling on membrane surface and greatly increase water flux by reducing the adsorption, deposition, blockage of membrane pores and formation of cake layer for two types of oil-in-water emulsion. For NF, water flux of the modified membrane increased by 66.1% and 22.8% for prepared oil-in-water emulsion and produced water, respectively. TiO2 coating effectively alleviated the oil adhesion and cake layer formation on the membrane surface.


Asunto(s)
Emulsiones/química , Membranas Artificiales , Contaminación por Petróleo , Piperazina/química , Polímeros/química , Sulfonas/química , Purificación del Agua/métodos , China , Emulsiones/aislamiento & purificación , Aceites Industriales , Nanopartículas , Yacimiento de Petróleo y Gas , Ultrafiltración/métodos , Ultrafiltración/normas
8.
J Clin Ultrasound ; 47(4): 247-252, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30614010

RESUMEN

Right ventricular (RV) wall dissection following ventricular septal rupture related to inferior myocardial infarction (MI) is an extremely rare complication with a high mortality rate. We report the case of a 61-year-old man who was admitted to our hospital because of syncope and intermittent chest pain with a precordial murmur. Transthoracic echocardiography showed a rupture at the basal infero-posterior septum and RV free-wall dissection forming an echolucent cavity that extended beyond the septum and subsequently re-entered into RV chamber. The patient's overall cardiac and renal functions deteriorated and he died 24 days after the diagnosis. We present a literature review of the published cases of complex dissecting tracts through the septum and RV wall in ischemic context.


Asunto(s)
Ecocardiografía/métodos , Infarto de la Pared Inferior del Miocardio/complicaciones , Infarto de la Pared Inferior del Miocardio/diagnóstico por imagen , Rotura Septal Ventricular/diagnóstico por imagen , Rotura Septal Ventricular/etiología , Enfermedad Aguda , Resultado Fatal , Ventrículos Cardíacos/diagnóstico por imagen , Humanos , Infarto de la Pared Inferior del Miocardio/terapia , Contrapulsador Intraaórtico , Masculino , Persona de Mediana Edad , Rotura Septal Ventricular/terapia
9.
Chemosphere ; 218: 252-258, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30471506

RESUMEN

Colloids and organics in shale gas fracturing flowback water (SGFFW) during shale gas extraction are of primary concerns. Coagulation combined with oxidation might be a promising process for SGFFW treatment. In this study, a novel electrocoagulation-peroxone (ECP) process was developed for SGFFW treatment by simultaneous coagulation and oxidation process with a Al plate as the anode and a carbon-PTFE gas diffusion electrode as the cathode, realizing the simultaneous processes of coagulation, H2O2 generation and activation by O3 at the cathode. Compared with electrocoagulation (EC) and peroxi-electrocoagulation (PEC), COD removal efficiency mainly followed the declining order of ECP, PEC and EC under the optimal current density of 50 mA cm-2. The appearance of medium MW fraction (1919 Da) during ozonation and PEC but disappearance in ECP indicated that these intermediate products couldn't be degraded by ozonation and PEC but could be further oxidized and mineralized by the hydroxyl radical produced by the cathode in ECP, demonstrating the hydroxyl radical might be responsible for the significant enhancement of COD removal. The pseudo-first order kinetic model can well fit ozonation and EC process but not the PEC and ECP process due to the synthetic effect of coagulation and oxidation. However, the proposed mechanism based model can generally fit ECP satisfactorily. The average current efficiency for PEC was 35.4% and 12% higher than that of ozonation and EC, respectively. This study demonstrated the feasibility of establishing a high efficiency and space-saving electrochemical system with integrated anodic coagulation and cathodic electro-peroxone for SGFFW treatment.


Asunto(s)
Técnicas Electroquímicas/métodos , Electrocoagulación/métodos , Fracking Hidráulico/métodos , Gas Natural , Compuestos Orgánicos/aislamiento & purificación , Purificación del Agua/métodos , Carbono , Electrodos , Radical Hidroxilo/química , Cinética , Oxidación-Reducción , Ozono , Ácidos Sulfúricos/química , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/aislamiento & purificación
10.
Medicine (Baltimore) ; 97(21): e10814, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29794766

RESUMEN

RATIONALE: Hashimoto's encephalopathy (HE) is associated with autoimmune thyroid disease and is complex, diverse, and easily misdiagnosed. However, if HE is diagnosed and treated in a timely manner, an optimal prognosis may be achieved. PATIENT CONCERNS: We presented a case of a 63-year-old female patient with paroxysmal dizziness, unsteady gait, emotion apathy, progressive cognitive impairment, and unusual magnetic resonance imaging (MRI) findings. DIAGNOSES: After suffering for almost 8 years, the patient was diagnosed with HE based on clinical manifestation, abnormal electroencephalogram, unusual MRI findings, sensitivity to cortisol treatment, and characteristic high antithyroid peroxidase antibody (TpoAb) titer. INTERVENTIONS: The patient continued regular glucocorticoids therapy after intravenous methylprednisolone pulse therapy, neurotrophic drugs, traditional Chinese medicine and rehabilitation to relieve hypermyotonia and cognitive impairment. OUTCOMES: After combined treatment, the patient's symptoms, electroencephalogram (EEG), MRI, and the TpoAb titer gradually improved. However, the patient had to stop glucocorticoids treatment because of severe osteoporosis, fractures and other adverse reactions. Her symptoms fluctuated, and her TpoAb titer increased again. LESSONS: HE may cause highly heterogeneous clinical features, particularly MRI findings. Withdrawal of the systematic glucocorticoids treatment can lead to varied outcomes in these patients.


Asunto(s)
Encefalopatías/complicaciones , Encefalitis/diagnóstico , Enfermedad de Hashimoto/complicaciones , Metilprednisolona/uso terapéutico , Administración Intravenosa , Autoanticuerpos/metabolismo , Encefalopatías/diagnóstico por imagen , Encefalopatías/patología , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/etiología , Mareo/diagnóstico , Mareo/etiología , Electroencefalografía , Encefalitis/complicaciones , Encefalitis/metabolismo , Encefalitis/terapia , Femenino , Trastornos Neurológicos de la Marcha/diagnóstico , Trastornos Neurológicos de la Marcha/etiología , Glucocorticoides/administración & dosificación , Glucocorticoides/efectos adversos , Glucocorticoides/uso terapéutico , Enfermedad de Hashimoto/diagnóstico , Enfermedad de Hashimoto/metabolismo , Enfermedad de Hashimoto/terapia , Humanos , Imagen por Resonancia Magnética , Metilprednisolona/administración & dosificación , Metilprednisolona/efectos adversos , Persona de Mediana Edad , Quimioterapia por Pulso/métodos , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
11.
Chemosphere ; 198: 83-91, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29421764

RESUMEN

In order to study the degradation of polycyclic aromatic hydrocarbons (PAHs) in an aged and highly contaminated soil, four bioremediation strategies (indigenous microorganisms, microbial bioaugmentation with a PAH-degrading and bioemulsifier-producing strain, Rhodococcus ruber Em1, plant bioaugmentation with Orychophragmus violaceus and their combination) were compared and the enhanced degradation mechanism was investigated in soil mesocosms. Degradation rates over a period of 175 days showed that Em1 combined with Orychophragmus violaceus promoted a significant enhancement of PAHs degradation. In inoculated microcosms with Rhodococcus ruberEm1, mineralization reached a lower level in the absence than in the presence of plants. Elimination of PAHs was significantly enhanced (increased by 54.45%) in the bioaugmented mesocosms. Quantitative PCR indicated that copy numbers of linA and RHD-like gene (encoding PAH-ring hydroxylating dioxygenase) in the mesocosm with plant were three and five times higher than those in the mesocosm without plant, respectively. Transcript copy numbers of RHD-like gene and 16S rRNA gene of strain Em1 in mesocosm with plant were two and four times higher than those in the mesocosm without plant, respectively. Taken together, the results of this study show that plants or Rhodococcus ruber Em1 enhance total PAHs removal, moreover their effects are necessarily cumulative by combined strains and plants.


Asunto(s)
Biodegradación Ambiental , Hidrocarburos Policíclicos Aromáticos/metabolismo , Rhodococcus , Microbiología del Suelo , Suelo/química , Brassicaceae/metabolismo , Hidrocarburos Policíclicos Aromáticos/análisis , ARN Ribosómico 16S/metabolismo , Rhodococcus/metabolismo
12.
Environ Sci Pollut Res Int ; 24(22): 18400-18409, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28643277

RESUMEN

Interactions of trace organic compounds (TOrCs) with polymeric nanofiltration (NF) membrane can affect their rejection. It is desirable to investigate whether solubility which depends on the free energy of interaction between these solutes and water correlates with rejection/adsorption and the potential to be incorporated in the partitioning terms of current NF model. A total of ten neutral disinfection by-products (DBPs) were selected as the model compounds for TOrCs to comprehensively investigate the role of solubility on rejection and adsorption. Pearson correlation analysis indicated that the correlation between MW and rejection ratio was highly significant (r = 0.778, p = 0.008) and that between solubility and rejection ratio was moderately significant (r = -0.636, p = 0.48) in a cross-flow system. By fitting Freundlich equation from adsorption isotherm experiment, the adsorption affinity (K f) of DBPs was roughly correlated with their solubility with regard to the comparison of n value with 1. α was then introduced as a parameter of solute-membrane interaction from the perspective of partitioning term in the hydrodynamic model. Exponential relationship can be observed between the solubility and α, demonstrating the possibility of incorporating solubility into the partitioning terms in NF model to accurately predict the rejection of DBPs.


Asunto(s)
Desinfectantes/análisis , Filtración/métodos , Membranas Artificiales , Compuestos Orgánicos/análisis , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Adsorción , Desinfectantes/química , Desinfección , Modelos Teóricos , Compuestos Orgánicos/química , Solubilidad , Contaminantes Químicos del Agua/química
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