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1.
Environ Sci Pollut Res Int ; 31(11): 17481-17493, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38342832

ABSTRACT

Excessive phosphorus will lead to eutrophication in aquatic environment; the efficient removal of phosphorus is crucial for wastewater engineering and surface water management. This study aimed to fabricate a nanorod-like sepiolite-supported MgO (S-MgO) nanocomposite with high specific surface area for efficient phosphate removal using a facile microwave-assisted method and calcining processes. The impact of solution pH, adsorbent dosage, contact time, initial phosphate concentrations, Ca2+ addition, and N/P ratio on the phosphate removal was extensively examined by the batch experiments. The findings demonstrated that the S-MgO nanocomposite exhibited effective removal performance for low-level phosphate (0 ~ 2.0 mM) within the pH range of 3.0 ~ 10.0. Additionally, the nanocomposite can synchronously remove phosphate and ammonium in high-level nutrient conditions (> 2.0 mM), with the maximum removal capacities of 188.49 mg P/g and 89.78 mg N/g. Quantitative and qualitative analyses confirmed the successful harvesting of struvite in effluent with high-phosphate concentrations, with the mechanisms involved attributed to a synergistic combination of sorption and struvite crystallization. Due to its proficient phosphate removal efficiency, cost-effectiveness, and substantial removal capacity, the developed S-MgO nanocomposite exhibits promising potential for application in phosphorus removal from aquatic environments.


Subject(s)
Magnesium Silicates , Nanocomposites , Water Pollutants, Chemical , Phosphorus/chemistry , Struvite/chemistry , Magnesium Oxide , Nitrogen , Phosphates/chemistry
2.
Environ Sci Pollut Res Int ; 30(41): 94401-94413, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37531060

ABSTRACT

A novel hierarchically nanostructured magnetite (Fe3O4) was manufactured using microwave-assisted reflux method without surfactants. The nanostructured Fe3O4 is formed via the co-precipitation of Fe(III) and Fe(II), followed by a nanocrystal aggregation-based mechanism. Moreover, the effects of solution pH, contact time, initial Sb concentration, coexisting anions, and recycle numbers on the adsorption of nanostructured Fe3O4 toward Sb were extensively examined in the batch adsorption tests. The results demonstrated that the obtained Fe3O4 exhibited excellent adsorption ability toward Sb with the maximum adsorption capacities of 154.2 and 161.1 mg.g-1 for Sb(III) and Sb(V), respectively. The prepared Fe3O4 could be easily regenerated and reused for adsorption/desorption studies multiple times without compromising the Sb adsorption ability. Further exploration indicated that the oxidation or reduction reactions infrequently occurred during Sb adsorption processes. The proposed hierarchically nanostructured Fe3O4 thus could be potentially used for sustainable and efficient antimony removal.


Subject(s)
Antimony , Water Pollutants, Chemical , Antimony/chemistry , Ferric Compounds/chemistry , Adsorption , Microwaves , Oxidation-Reduction
3.
Acad Radiol ; 27(6): e140-e147, 2020 06.
Article in English | MEDLINE | ID: mdl-31582193

ABSTRACT

RATIONALE AND OBJECTIVES: To determine the optimal keV for the visualization of gastric cancer and to investigate its value in depicting lesions and in identifying depth invasion using virtual monoenergetic images (VMIs) on a novel dual-layer spectral detector CT. MATERIALS AND METHODS: Eighty-two gastric cancer patients were retrospectively enrolled, and 41 patients who did not undergo surgery were evaluated for image quality in VMIs at different keVs (40 keV-70 keV with 10 keV increments) and in conventional 120 kVp polyenergetic images (PEIs) reconstructed from the portal venous phase. Objective image quality was assessed by the contrast-to-noise ratio of the gastric cancer, while subjective performance was compared using a 5-point Likert scale. Another 41 patients who underwent surgery were examined to compare the diagnostic performance of the VMIs taken at the optimal keV and that of the 120 kVp-PEIs. RESULTS: The contrast-to-noise ratio of gastric cancer at 40 keV (10.4 ± 4.6) was the highest among all the VMIs and was significantly superior to that of the 120 kVp-PEIs (3.5 ± 1.5, p < 0.001). Gastric-specific image quality was rated highest for the 40 keV-VMIs (4.92 ± 0.26), which was significantly superior to that of the 120 kVp-PEIs (4.15 ± 0.82, p < 0.001). In the diagnostic group, there were 13 pT1, 10 pT2, 9 pT3, and 9 pT4 gastric cancer patients. Compared with the 120 kVp-PEIs, the VMIs at 40 keV tended to have a higher detection rate of gastric cancer (82.9% vs. 92.7%, respectively, p = 0.125) and a significantly improved diagnostic accuracy in the T stage (from 41.5% to 78.11%, respectively) (p < 0.001), particularly in pT1 patients, whose diagnostic accuracy was improved by 53.8% (7.7% vs. 61.5%, respectively, p = 0.016). CONCLUSION: VMIs at 40 keV performed the best, both objectively and subjectively, for gastric cancer, leading to improved lesion depiction and higher T stage accuracy.


Subject(s)
Radiography, Dual-Energy Scanned Projection , Stomach Neoplasms , Humans , Retrospective Studies , Signal-To-Noise Ratio , Stomach Neoplasms/diagnostic imaging , Tomography, X-Ray Computed
4.
World Neurosurg ; 122: e1381-e1387, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30465955

ABSTRACT

OBJECTIVE: Data reporting percutaneous vertebroplasty (PVP) or percutaneous balloon kyphoplasty (PKP) application to the midthoracic vertebrae remain limited. This study aimed to summarize our experiences and explore the efficacy and safety of PVP or PKP in dealing with osteoporotic vertebral compression fracture (OVCF) in the midthoracic vertebrae. METHODS: Patients receiving PVP or PKP for midthoracic OVCF in our institution from January 2015 to January 2018 were retrospectively enrolled. All patients were grouped according to cement augmentation procedure types, surgical approaches, and puncture routes. All patients underwent a postoperative follow-up of 2-36 months. Visual analog scale (VAS) and ECOG Scale of Performance Status scores were evaluated pre- and postoperatively. Cement distribution and rate of cement leakage were assessed by radiographs. Associations of these variables and clinical scores and radiographic indices were analyzed. RESULTS: A total of 101 consecutive patients with 111 fractured centrums were enrolled. Both VAS and ECOG Scale of Performance Status scores of all patients decreased significantly after the operation, and progressively decreased at the final follow-up. The cement distribution of the bipedicular group was significantly better than the unipedicular group, but the total leakage rate of the former (71.7%) was significantly higher than the latter (43.1%). The rate of epidural cement leakage in the PKP group (5.4%) was significantly lower than that of the PVP group (20.3%), whereas the left puncture group (28.6%) was significantly higher than that of the right puncture group (2.7%). CONCLUSIONS: PKP and a bipedicular approach can help improve cement distribution and reduce the epidural cement leakage rate and therefore should be preferred over PVP or a unipedicular approach in OVCF of the midthoracic vertebrae.


Subject(s)
Fractures, Compression/surgery , Kyphoplasty/methods , Osteoporotic Fractures/surgery , Spinal Fractures/surgery , Vertebroplasty/methods , Aged , Aged, 80 and over , Bone Cements/therapeutic use , Extravasation of Diagnostic and Therapeutic Materials/prevention & control , Female , Humans , Male , Middle Aged , Pain, Postoperative/etiology , Postoperative Complications/etiology , Retrospective Studies , Thoracic Vertebrae/surgery , Treatment Outcome
5.
J Colloid Interface Sci ; 510: 280-291, 2018 Jan 15.
Article in English | MEDLINE | ID: mdl-28957744

ABSTRACT

Ag2O nanoparticles anchored on the Mg(OH)2 nanoplates (Ag2O@Mg(OH)2) were successfully prepared by a facile one-step method, which combined the Mg(OH)2 formation with Ag2O deposition. The synthesized products were characterized by a wide range of techniques including powder X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and nitrogen physisorption analysis. It was found that Ag2O nanoparticles anchored on the Mg(OH)2 nanoplates show good dispersion and less aggregation relative to the single Ag2O nanoaggregates. In addition, iodide (I-) removal by the Ag2O@Mg(OH)2 nanocomposite was studied systematically. Batch experiments reveal that the nanocomposite exhibits extremely high I- removal rate (<10min), and I- removal capacity is barely affected by the concurrent anions, such as Cl-, SO42-, CO32- and NO3-. Furthermore, I- and UO22+ could be simultaneously removed by the nanocomposite with high efficiency. Due to the simple synthetic procedure, the excellent removal performances for iodine and uranium, and the easy separation from water, the Ag2O@Mg(OH)2 nanocomposite has real potential for application in radioactive wastewater treatment, especially during episodic environmental crisis.

6.
ACS Appl Mater Interfaces ; 6(13): 10556-65, 2014 Jul 09.
Article in English | MEDLINE | ID: mdl-24892188

ABSTRACT

Hollow core/shell hematite microspheres with diameter of ca. 1-2 µm have been successfully achieved by calcining the precursor composite microspheres of pyrite and polyvinylpyrrolidone (PVP) in air. The synthesized products were characterized by a wide range of techniques including powder X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), and Brunauer-Emmett-Teller (BET) gas sorptometry. Temperature- and time-dependent experiments unveil that the precursor pyrite-PVP composite microspheres finally transform into hollow core/shell hematite microspheres in air through a multistep process including the oxidation and sulfation of pyrite, combustion of PVP occluded in the precursor, desulfation, aggregation, and fusion of nanosized hematite as well as mass transportation from the interior to the exterior of the microspheres. The formation of the hollow core/shell microspheres dominantly depends on the calcination temperature under current experimental conditions, and the aggregation of hematite nanocrystals and the core shrinking during the oxidation of pyrite are responsible for the formation of the hollow structures. Moreover, the adsorption ability of the hematite for Sm(III) was also tested. The results exhibit that the hematite microspheres have good adsorption activity for trivalent samarium, and that its adsorption capacity strongly depends on the pH of the solution, and the maximum adsorption capacity for Sm(III) is 14.48 mg/g at neutral pH. As samarium is a typical member of the lanthanide series, our results suggest that the hollow hematite microspheres have potential application in removal of rare earth elements (REEs) entering the water environment.

7.
Yao Xue Xue Bao ; 45(2): 215-23, 2010 Feb.
Article in Chinese | MEDLINE | ID: mdl-21351431

ABSTRACT

HIV-1 integrase (IN) is an essential enzyme for retroviral replication. There is no analogue for this enzyme in human cells so that inhibition of IN will not bring strong effect on human body. Thus, HIV-1 IN has become a rational target for therapy of AIDS. This review provides a comprehensive report of alpha, gamma-diketo IN inhibitors discovered in recent years. Compilation of such data will prove to be beneficial in developing QSAR, pharmacophore hypothesis generation and validation, virtual screening and synthesis of compounds with higher activity.


Subject(s)
Anti-HIV Agents , HIV Integrase Inhibitors , HIV-1/drug effects , Keto Acids , Anti-HIV Agents/chemical synthesis , Anti-HIV Agents/chemistry , Anti-HIV Agents/pharmacology , HIV Integrase/chemistry , HIV Integrase/physiology , HIV Integrase Inhibitors/chemical synthesis , HIV Integrase Inhibitors/chemistry , HIV Integrase Inhibitors/pharmacology , Humans , Keto Acids/chemical synthesis , Keto Acids/chemistry , Keto Acids/pharmacology , Molecular Structure , Quantitative Structure-Activity Relationship
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