Electrocatalytic Degradation of Rhodamine B on the Sb-Doped SnO2/Ti Electrode in Alkaline Medium.

To realize efficient electrocatalytic degradation of organic compounds in alkaline wastewater, an Sb-doped SnO2/Ti electrode was fabricated and employed for the removal of Rhodamine B (RhB), and the electrocatalytic oxidation performance of this electrode was assessed in an alkaline medium. In an alkaline solution (pH 11), the complete fading of 50 mg·L-1 RhB could be achieved after 150 min of degradation, the removal efficiency of the chemical oxygen demand reached 56.1% at 300 min, and the degradation process of RhB followed the pseudo-first-order kinetic model very well. Under the attack of hydroxyl radicals, partial RhB was degraded to low-molecular-weight organic acids through N-demethylation and the destruction of the conjugated chromophore. Various techniques including scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and cycle voltammetry were used to examine the changes in the morphology and structure, as well as the activity of the Sb-doped SnO2/Ti electrode before and after use. The Sb-doped SnO2/Ti electrode could be reproduced in batches, and each electrode was reused up to eight times without a significant decrease in degradation ability; the leaching amount of antimony was significantly lower than the national emission standard. The electrocatalytic oxidation of the dye wastewater sample was also performed with the desired results, indicating that electrochemical oxidation is a very promising technology for the treatment of alkaline dye wastewater using a Sb-doped SnO2/Ti electrode.

Enhanced Reactive Brilliant Blue Removal Using Chitosan-Biochar Hydrogel Beads.

To address the challenges associated with the weak affinity and difficult separation of biochar, we developed chitosan-biochar hydrogel beads (CBHBs) as an efficient solution for removing reactive brilliant blue (RBB KN-R) from wastewater. The adsorption behavior and mechanism of RBB KN-R onto CBHBs were extensively studied. Notably, the adsorption capacity of RBB KN-R showed pH-dependence, and the highest adsorption capacity was observed at pH 2. The adsorption process was well fitted with the pseudo-second-order kinetic model and the intraparticle diffusion model. Film diffusion and intraparticle diffusion were both responsible for the adsorption of RBB KN-R onto CBHBs. At 298.15 K, the maximum adsorption capacity qm was determined to be 140.74 mg/g, with higher temperatures favoring the adsorption process. A complex mechanism involving π-π interactions, electrostatic attraction, hydrophobic interaction, and hydrogen bonding was found to contribute to the overall adsorption process. The experimental data discovered the coexisting substances and elevated ionic strength hindered the adsorption capacity. Significantly, after three cycles of adsorption-desorption, the CBHBs maintained an adsorption capacity above 95% for RBB KN-R. These promising results imply that CBHBs are a durable and cost-effective adsorbent for efficient removal of dyes from wastewater.

Preparation of multi-walled carbon nanotubes based magnetic multi-template molecularly imprinted polymer for the adsorption of phthalate esters in water samples.

Taking the advantages of surface imprinting, multi-template imprinting and magnetic separation, a novel magnetic multi-template molecularly imprinted polymer (mag-MMIP@MWCNTs) was prepared by using MWCNTs as support material, Fe3O4 as magnetic core, and dimethyl phthalate (DMP), diethyl phthalate (DEP), and dibutyl phthalate (DBP) as template molecules. This composite was characterized by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), vibrating sample magnetometer (VSM), and the Brunauer-Emmett-Teller (BET) analysis, and was used for the simultaneous adsorption of DMP, DEP, and DBP in aqueous solution. The effects of solution pH, contact time, PAEs initial concentration, temperature, adsorption selectivity, and reusability were investigated and discussed in detail. The results demonstrated that mag-MMIP@MWCNTs exhibited fast kinetics, good magnetic separation, and excellent selectivity for the adsorption of three phthalate esters (PAEs). The adsorption kinetics followed pseudo second-order kinetic model and the adsorption thermodynamics followed Langmuir isothermal model very well, and the maximum adsorption capacities (Qmax) of DMP, DEP, and DBP were obtained as 0.95, 1.38, and 7.09 mg g-1, respectively. The Scatchard analysis revealed that the template-polymer system had a two-site binding behavior. The adsorption thermodynamic studies indicated that the adsorption processes were exothermic and spontaneous, and dominated by physical adsorption relying on hydrogen bond, hydrophobic interaction, and van der Waals force. Mag-MMIP@MWCNTs also showed good reproducibility and reusability for simultaneous adsorption of the three PAEs. The potential application of mag-MMIP@MWCNTs was proved by the removal of DMP, DEP, and DBP spiked in environmental water samples.

Clinical features and underlying genetic causes in neonatal encephalopathy: A large cohort study.

This study aimed to investigate the potential genetic causes of neonatal encephalopathy (NE) in a large cohort of Chinese patients. We included 366 neonates with encephalopathy. Whole exome sequencing was performed to assess the potential molecular defects. In this study, 43 patients (11.7%) were identified with pathogenic or likely pathogenic variants and 10 patients (2.7%) carried variants with unknown significance. Compared with patients without genetic findings (28.9%), patients with genetic findings (96.2%) displayed a significant higher incidence of seizure (P = .0009); however, a lower frequency of abnormal magnetic resonance imaging (MRI) results (P < .0001). Epileptic encephalopathy related genes account for nearly half (46.4%) of all genetic defects of NE with seizures. Follow-up results revealed genetic diagnosis, seizure and severe abnormal electroencephalograph results were significantly associated with high risk of developmental delay (P < .05). This study increases the understanding of genetic contribution to NE. Our findings suggest that the full-term NE patients with seizure, the greater the possibility of genetic diseases. However, for newborns especially the preterm babies with abnormal MRI findings, there is smaller possibility of genetic diseases. NE caused from genetic diseases have poor prognosis, and intensive intervention and follow-up is necessary for these newborns.

Electrochemical degradation of three phthalate esters in synthetic wastewater by using a Ce-doped Ti/PbO2 electrode.

A Ce-doped Ti/PbO2 electrode was prepared in a deposition solution containing Ce3+ and Pb2+ ions by electrodeposition, and the surface morphology, crystal structure and elemental states were characterized by SEM, XRD and XPS. The electrode was used to investigate the simultaneous degradation of three phthalate esters (PAEs), i.e., dimethyl phthalate (DMP), diethyl phthalate (DEP) and dibutyl phthalate (DBP) in synthetic wastewaters. The results showed that the electrode exhibited excellent electrocatalytic activity and good reusability and stability, and the removal efficiencies of 5 mg L-1 DBP, DMP and DEP in 0.05 M Na2SO4 (pH 7) reached 98.2%, 95.8% and 81.1% at current density of 25 mA cm-2 after 10 h degradation, respectively. The degradation processes followed pseudo first-order kinetic model very well, and the observed rate constants of DBP, DEP and DMP were 0.42, 0.40 and 0.29 h-1, respectively. The energy consumption in three PAEs degradation was also assessed. The main degradation products of the three PAEs were identified by using liquid chromatography-tandem mass spectrometry, and the possible degradation pathways mainly included dealkylation, hydroxyl addition, decarboxylation and benzene ring cleavage. This work is a promising candidate for efficient treatment of multiple PAEs in wastewater and protection of the aquatic ecological environment.

Electrocatalytic reduction of low-concentration thiamphenicol and florfenicol in wastewater with multi-walled carbon nanotubes modified electrode.

The electrocatalytic reduction of thiamphenicol (TAP) and florfenicol (FF) was investigated with multi-walled carbon nanotubes (MWCNTs) modified electrode. MWCNTs was dispersed in pure water with the assistance of dihexadecyl phosphate (DHP), and then modified on glassy carbon electrode (GCE). The electrocatalytic reduction conditions, such as bias voltage, supporting electrolyte and its initial pH, and the initial concentrations of TAP and FF, were also optimized. The experimental results indicated that the removal efficiencies of 2mgL-1 TAP and FF in 0.1M NH3·H2O-NH4Cl solution (pH 7.0) reached 87% and 89% at a bias voltage of -1.2V after 24h electrocatalytic reduction, respectively. The removal process could be described by pseudo first-order kinetic model, and the removal rate constants of TAP and FF were obtained as 0.0837 and 0.0915h-1, respectively. The electrocatalytic reduction products of TAP and FF were identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS), and the possible reduction mechanisms were preliminarily analyzed. Electrocatalytic reduction is promising to remove low-concentration TAP and FF in wastewater with the MWCNTs modified electrode, and may cut down their toxicity through dehalogenation and carbonyl reduction.

Determination of ephedrine and pseudoephedrine by field-amplified sample injection capillary electrophoresis.

A simple and rapid capillary electrophoresis method was developed for the separation and determination of ephedrine (E) and pseudoephedrine (PE) in a buffer solution containing 80 mM of NaH2PO4 (pH 3.0), 15 mM of ß-cyclodextrin and 0.3% of hydroxypropyl methylcellulose. The field-amplified sample injection (FASI) technique was applied to the online concentration of the alkaloids. With FASI in the presence of a low conductivity solvent plug (water), an approximately 1,000-fold improvement in sensitivity was achieved without any loss of separation efficiency when compared to conventional sample injection. Under these optimized conditions, a baseline separation of the two analytes was achieved within 16 min and the detection limits for E and PE were 0.7 and 0.6 µg/L, respectively. Without expensive instruments or labeling of the compounds, the limits of detection for E and PE obtained by the proposed method are comparable with (or even lower than) those obtained by capillary electrophoresis laser-induced fluorescence, liquid chromatography-tandem mass spectrometry and gas chromatography-mass spectrometry. The method was validated in terms of precision, linearity and accuracy, and successfully applied for the determination of the two alkaloids in Ephedra herbs.

Acoustic radiation force impulse (ARFI) imaging of preliminary mucosa associated lymphoid tissue (MALT) lymphoma in the breast: a case report.

Primary lymphoma is a rare neoplasm in the breast accounting for between 0.04% and 0.5% of all malignant mammary tumors. The majority of cases lack typical features of breast malignancy or lymphoma, and likely to be misdiagnosed during daily clinical practice. In this report we describe a case of primary breast lymphoma assessed with acoustic radiation force impulse (ARFI) technology.

Monolithic molecular imprinted polymer fiber for recognition and solid phase microextraction of ephedrine and pseudoephedrine in biological samples prior to capillary electrophoresis analysis.

A novel capillary electrophoresis (CE) method coupled with monolithic molecular imprinted polymer (MIP) fiber based solid phase microextraction (SPME) was developed for selective and sensitive determination of ephedrine (E) and pseudoephedrine (PE). With in situ polymerization in a silica capillary mold and E as template, the MIP fibers could be produced in batch reproducibly and each fiber was available for 50 extraction cycles without significant decrease in extraction ability. Using the MIP fiber under optimized extraction conditions, CE detection limits of E and PE were greatly lowered from 0.20 to 0.00096 µg/mL and 0.12 to 0.0011 µg/mL, respectively. Analysis of urine and serum samples by the MIP-SPME-CE method was also performed, with results indicating that E and PE could be selectively extracted. The recoveries and relative standard deviations (RSDs) for sample analysis were found in the range of 91-104% and 3.8-9.1%, respectively.

Simultaneous stacking of cationic and anionic compounds in single run capillary zone electrophoresis by two-end field amplified sample injection.

In order to extend the application of field amplified sample injection (FASI) in high throughput analysis, a convenient and simple procedure, namely two-end field amplified sample injection (TE-FASI), was developed for the simultaneous stacking of cationic and anionic compounds in a single run capillary zone electrophoresis (CZE). Following the capillary-filling with a buffer of high conductivity, water plug was loaded into each end of the capillary; and two high-field strength zones were generated at both heads of the column when high voltage was applied. Therefore, under suppressed EOF cations and anions can be selectively FASI stacked at anode and cathode head, respectively. After separation, the stacked anions and cations are detected by a common detector placed in the center of the capillary. Under the optimized conditions, the limits of detection for the model cationic (matrine and oxymatrine) and anionic (5-sulfosalicylic acid) compounds were determined as 0.2, 0.2 and 0.06 ng/mL, respectively. Compared with non-stacking conditions, the sensitivities of these compounds were enhanced 1003-, 1330- and 1380-fold, respectively. The results of reproducibility, linearity and real sample analysis show that the proposed procedure is promising to be applied for the simultaneous quantification detection of trace cationic and anionic analytes.