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1.
Molecules ; 29(16)2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39202820

RESUMEN

In this study, a glaze slurry was prepared with different contents of tricalcium phosphate. It was then applied to a fly ash microcrystalline ceramic billet and sintered at 1180 °C for 30 min to prepare the complex. The aim was to obtain a high value-added application of fly ash in order to reduce environmental pollution. The study systematically investigated the influence of the Ca3(PO4)2 content on the crystal phase evolution, physical-mechanical properties, and micro-morphology of the complex. The results showed that products sintered at 1180 °C with 8 wt% Ca3(PO4)2 demonstrated better performance, with a water absorption of 0.03% and a Vickers microhardness of 6.5 GPa. Additionally, the study observed a strong correlation between the Ca3(PO4)2 content and the opacity effect. A feasible opacity mechanism was also proposed to explain the variation of glaze colors and patterns with different contents of Ca3(PO4)2.

2.
Materials (Basel) ; 17(16)2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39203331

RESUMEN

The expansion of vermiculite using microwave irradiation is an environmentally friendly and efficient method that can enhance the material's adsorption performance. This study investigated the microwave irradiation of vermiculite with five different particle sizes (4/2/1/0.5/0.2 mm) and found that the adsorption capacity for Pb2+ increased with larger particle sizes. The equilibrium adsorption capacity reached 15.98 mg/g at 4 mm, representing a 45.01% improvement compared to 0.2 mm. The pseudo-second-order kinetic model effectively described the adsorption kinetics. No significant differences were observed in the specific surface area and pore size distribution of all samples. Thermogravimetric quantitative analysis revealed that larger particle sizes retained interlayer water more effectively. As the particle size decreased, the interlayer water content generally showed a decreasing trend. Fourier-transform infrared spectroscopy analysis also indicated that the -OH groups in larger particle sizes exhibited higher stability. The results suggest that the high content and stability of -OH groups may be key factors in the enhanced adsorption performance for Pb2+. This provides new insights for the preparation of environmentally friendly adsorbent materials rich in hydroxyl groups.

3.
Diabetes Metab Syndr Obes ; 17: 1761-1767, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38645660

RESUMEN

Background: Type 2 diabetes mellitus (T2DM) poses a huge threat to population health globally, and more drugs need to be explored for treatment. In this study, we investigated the mechanism of active ingredient catalpol in Rehmannia glutinosa on reduces blood glucose in diabetic. Methods: The T2DM model was constructed by intraperitoneal injection of streptozotocin into Sprague-Dawley (SD) rats, which were randomly grouped into diabetes model group, pioglitazone group, Rehmannia glutinosa group, catalpol high-dose group, catalpol low-dose group and normal control group.The intervention was continued for 28 d, and changes in body weight, fasting blood glucose, insulin and lipid levels were observed. Results: Of all the drugs, pioglitazone had the most pronounced hypoglycemic effect, which began to decline after 2 weeks of treatment in the low-dose catalpol group and had no hypoglycemic effect in the high-dose catalpol group. Among them, Rehmannia glutinosa was able to increase serum triglyceride level, and pioglitazone effectively reduced total cholesterol level in rats. The low dose of catalpol decreased the concentration of low-density lipoprotein cholesterol (LDL), while the high dose of catalpol increased the concentration of LDL. Conclusion: As an active ingredient in Rehmannia glutinosa, catalpol has the potential to lower blood glucose and improve blood lipids in diabetes treatment, and its action may be achieved by regulating the adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) signaling pathway, which provides a new idea for the development of new diabetes therapeutic approaches.

4.
Front Med (Lausanne) ; 10: 1285753, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38046412

RESUMEN

In this report, the case of a 65-year-old immunosuppressed female who presented with recurring redness and irritation in her right eye for 2 months is described. Ocular examination revealed conjunctival congestion, feather-like greyish-white corneal deep stromal infiltrate, white, floccular material sprawling from the anterior chamber angle and hypopyon. The in vivo confocal microscopy (IVCM) instantly confirmed fungal keratitis, and empirical antifungal therapy was thus administered. The patient exhibited therapeutic penetrating keratoplasty, however, due to the progression of infection and the lack of identified pathogens. The fungal isolate was identified as Corynespora cassiicola by metagenomic next-generation sequencing (mNGS) of the host cornea. The patient responded well to intensive conservative therapy and subsequent surgical therapy. To our knowledge, this case represents the first case of C. cassiicola infection from China, highlighting the emergence of a rare fungus that causes keratitis. Furthermore, mNGS has the capability to facilitate prompt identification and timely management of challenging ocular infections that are difficult to diagnose.

6.
Environ Microbiol Rep ; 15(6): 545-556, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37537784

RESUMEN

Salinity is an important environmental factor in microbial ecology for affecting the microbial communities in diverse environments. Understanding the salinity adaptation mechanisms of a microbial community is a significant issue, while most previous studies only covered a narrow salinity range. Here, variations in seawater prokaryotic communities during the whole salt drying progression (salinity from 3% to 25%) were investigated. According to high-throughput sequencing results, the diversity, composition, and function of seawater prokaryotic communities varied significantly along the salinity gradient, expressing as decreased diversity, enrichment of some halophilic archaea, and powerful nitrate reduction in samples with high salt concentrations. More importantly, a sudden and dramatic alteration of prokaryotic communities was observed when salinity reached 16%, which was recognized as the change point. Combined with the results of network analysis, we found the increasing of complexity but decreasing of stability in prokaryotic communities when salinity exceeded the change point. Moreover, prokaryotic communities became more deterministic when salinity exceeded the change point due to the niche adaptation of halophilic species. Our study showed that substantial variations in seawater prokaryotic communities along an extremely wide salinity gradient, and also explored the underlying mechanisms regulating these changes.


Asunto(s)
Archaea , Microbiota , Archaea/genética , Salinidad , Células Procariotas , Agua de Mar , Cloruro de Sodio
7.
Materials (Basel) ; 16(7)2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-37049137

RESUMEN

Titanium-extracted tailing slag (TETS) has high activity, but the content of chloride ions is high. To effectively bind the chloride ions, CaO was used to activate the TETS, and the solidified cementitious material of CaO-activated TETS was prepared. The effects of CaO content and curing age on the strength of solidified samples, chloride binding capacity, and chloride binding mechanism were studied. By means of XRD, FTIR, SEM, and EDS, the hydration reaction products, microstructure, morphology, and micro-components of the solidified sample were characterized. The results show that the chloride ions can be effectively bound by using CaO to activate TETS with higher mechanical strength. When the CaO content is 10 wt%, the strength of the 28-day-cured body can reach more than 20 MPa, the chloride ion binding amount is 38.93 mg/g, and the chloride binding rate is as high as 68%. The new product phases of the solidified sample are mainly Friedel's salt (FS) and calcite, in which the amount of FS production and the degree of crystal development are affected by the CaO content and curing age. The chloride binding ions in the solidified sample are mainly the chemical binding by FS. The FS diffraction peak strength increases with the increase of CaO content and curing age, but the calcite diffraction peak strength is less affected by them. FS mainly accumulates and grows in the pores of the solidified sample. It can optimize the pore structure of the solidified sample and improve the strength of the solidified sample while binding chloride ions. The results can provide useful information for the resource utilization of chlorine-containing TETS, the improvement of durability of Marine concrete, and the application of sea sand in concrete.

8.
Exp Ther Med ; 25(4): 157, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36911369

RESUMEN

The present study aimed to examine the clinical and pathogenic characteristics, diagnosis and treatment of primary canaliculitis to provide further guidance for its clinical management. The present prospective study enrolled 50 patients (50 eyes) diagnosed with primary canaliculitis between May 2018 and April 2021 at Department of Ophthalmology, Affiliated Wuxi Clinical College of Nantong University, Wuxi, China. The patients' general clinicopathological information, clinical characteristics, microbiological profiles and treatment outcomes were analyzed and summarized. All the patients presented with persistent red eyes and eye discharge. Examination of discharge smears revealed that 96% of patients tested positive for Actinomyces and all smears were negative for fungi. Microbial cultures indicated that 82% of cases were positive for bacteria. A total of 51 bacterial strains were cultured; of these, 27.5% were aerobes, 35.3% were anaerobes and 37.2% were facultative anaerobes. A total of 56.9% of strains were gram-positive and 43.1% were gram-negative. The three most common bacteria, including Streptococcus spp., Capnocytophaga spp. and Propionibacterium, were analyzed. Only 3 cases (6%) of microbial cultures were positive for Actinomyces and all cases were negative for fungi in microbial cultures. Among the 50 cases, 45 were cured with conservative treatment [intracanalicular ointment infiltration (IOI)]. Five patients responded poorly to conservative treatment; however, they were cured with surgical treatment. In the current study, the majority of canaliculitis cases were caused by mixed infections, predominantly Actinomyces. The results revealed that the culture positivity rate of Actinomyces was low; however, the smear staining positivity rate was high. Fungus was smear- and culture-negative in all cases. In conclusion, patients with canaliculitis had a good prognosis after timely diagnosis and treatment.

9.
Materials (Basel) ; 16(3)2023 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-36769944

RESUMEN

Hardened pastes with different mass percentages of steel slag (SS)/titanium-extracted tailing slag (TETS) were prepared under fixed CaO content to determine the influencing mechanism of TETS on the strength of CaO SS hardened paste. Furthermore, the effects and laws of curing time and SS/TETS ratios on the strength of hardened pastes were also investigated in this study. Importantly, hydration products, microstructures and the micro-area compositions of hardened pastes were analysed using X-ray diffraction, Fourier-transform infrared spectroscopy and scanning electron microscopy-energy dispersive spectrometer, respectively, to reveal the influencing mechanism of TETS on the CaO SS hardened pastes. The results demonstrated that the early strength of hardened pastes increases considerably following the inclusion of TETS. Specifically, the strength of the sample with an SS/TETS ratio of 22.5:67.5 at 1 d can be increased by more than 14 times. Notably, its strength at 90 days reached 19.36 MPa. Moreover, the diffraction peaks of calcite and C-S-H in the samples were also strengthened. Meanwhile, a diffraction peak of hydrocalumite appeared, and the calcites in the samples were curled up. When the SS/TETS ratio was equal to or more than 45:45, a diffraction peak of Ca(OH)2 appeared in the sample. Only a diffraction peak of Ca(OH)2 and weak diffraction peaks of calcite and C-S-H were observed in the samples without TETS, but there was no diffraction peak of hydrocalumite. The strength at 90 days was only 4.92 MPa. The increased strength of the hardened paste is closely related to the production of new phases after adding TETS. Solid particles in the hardened paste are cemented into a whole because of the hydration of C-S-H. Calcite forms the skeleton of the hardened pastes, whereas hydrocalumite fills in the pores among particles in hardened pastes, thus making them more compacted. As a result, there is increased.

10.
Molecules ; 28(3)2023 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-36770619

RESUMEN

In this study, the effect of citric acid on iron leaching from titanium gypsum (TiG) was systematically investigated. The conditions for the leaching of valuable metals were optimized while varying such parameters as the leaching time, citric acid mass fraction, leaching temperature, and the liquid-solid ratio. It was found that under the conditions of a citric acid mass fraction of 10%, at a 80 °C leaching temperature, a leaching duration of 80-90 min and a liquid-solid ratio of 8, the whiteness of titanium gypsum (TiG) increased from 8.1 to 36.5, and the leaching efficiencies of iron reached 84.37%. The kinetic analysis indicated that the leaching process of iron from TiG was controlled by the reaction product layer from 0-20 min, while the leaching process of iron from TiG was controlled by internal diffusion from 20-90 min. The apparent activation energy of the leaching reactions was 33.91 kJ/mol and 16.59 kJ/mol, respectively. High-value-added calcium oxalate and ferrous oxalate were prepared from the calcium and iron in the filtrate of the oxalic acid extraction. The leaching liquid could be recycled, which will provide a new way to utilize titanium gypsum.

11.
Molecules ; 28(2)2023 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-36677875

RESUMEN

The structure and activity of vermiculite can be maintained by expanding vermiculite (Vrm) with hydrogen peroxide. However, it is time-consuming. In past studies, little attention has been paid to the catalytic properties of manganese dioxide on hydrogen peroxide to improve the swelling efficiency of vermiculite. In this experiment, this catalytic effect was utilized to swell Vrm in a short time. The samples were then used to adsorb Cd from the solution. Through a series of characterization tests. The results showed that the exothermic rate was 1960.42-2089.164 J/min and the total exothermic heat was 39,208.4-41,783.28 J when expanding 10 gVrm, which could have a good expansion effect. The expansion was completed in about 40 min. Compared with Vrm, the adsorption of Cd is enhanced by about 30%. It is consistent with the proposed secondary kinetic adsorption model. This study provides a new perspective and theoretical guidance for improving the efficiency of Vrm stripping by hydrogen peroxide. A kind of expanded Vrm with better Cd adsorption efficiency was also prepared.

12.
RSC Adv ; 12(54): 34990-35001, 2022 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-36540258

RESUMEN

The potential-pH diagrams of the main components of Ti-bearing blast furnace slag (air-cooled slag) at 298.15 K (25 °C) and an ion activity of 1.00 were drawn by thermodynamic calculation. Thermodynamic analysis showed that the main metal components, when the Ti-bearing blast furnace slag is roasted with concentrated sulfuric acid, could be converted to sulfate. From these analyses, it can be seen that under strong acid conditions, the major metal components could react to form sulfate, and the effective separation of Ti, Mg, and Al can be achieved from both Ca and Si. Further experiments were performed with a 5.0% dilute sulfuric acid solution used to leach a Ti-bearing blast furnace slag sample that had been calcined with concentrated sulfuric acid, at a liquid-solid ratio of 10, a reaction time of 60 min, and a reaction temperature of 338.15 K (65 °C). This led to a leaching ratio of Ti above 85.0%, leaching ratios of Mg and Al higher than 95.0%, and leaching ratios of Fe and Ca of 45.7% and 24.7%, respectively. All these values were higher than the leaching ratios of Ti-bearing blast furnace slag.

13.
Materials (Basel) ; 15(23)2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-36499902

RESUMEN

A series of three-dimensional porous composite α-MnO2/reduced graphene oxides (α-MnO2/RGO) were prepared by nano-assembly in a hydrothermal environment at pH 9.0-13.0 using graphene oxide as the precursor, KMnO4 and MnCl2 as the manganese sources and F- as the control agent of the α-MnO2 crystal form. The α-MnO2/RGO composites prepared at different hydrothermal pH levels presented porous network structures but there were significant differences in these structures. The special pore structure promoted the migration of ions in the electrolyte in the electrode material, and the larger specific surface area promoted the contact between the electrode material and the electrolyte ions. The introduction of graphene solved the problem of poor conductivity of MnO2, facilitated the rapid transfer of electrons, and significantly improved the electrochemical performance of materials. When the pH was 12.0, the specific surface area of the 3D porous composite material αMGs-12.0 was 264 m2·g-1, and it displayed the best super-capacitive performance; in Na2SO4 solution with 1.0 mol·L-1 electrolyte, the specific capacitance was 504 F·g-1 when the current density was 0.5 A·g-1 and the specific capacitance retention rate after 5000 cycles was 88.27%, showing that the composite had excellent electrochemical performance.

14.
Fish Shellfish Immunol ; 131: 1275-1281, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36400371

RESUMEN

The lysin motif (LysM)-containing protein is one of widespread pattern-recognition receptors in prokaryotes and eukaryotes. Numerous LysM-containing gene sequences are present in gene databases; however, few have been well characterized, especially in echinoderms. In this study, the full-length cDNA of a novel LysM-containing gene was obtained from the sea cucumber Apostichopus japonicus, named AjLysM-1, using polymerase chain reaction (PCR) combined with rapid amplification of cDNA ends. We prepared and expressed recombinant AjLysM-1 protein (rAjLysM-1) and determined its pathogen-recognition ability by enzyme-linked immunosorbent and immunofluorescence assays. We also analyzed the tissue expression pattern and response to immune challenges of AjLysM-1 using quantitative real-time reverse transcription-PCR and in situ hybridization. The AjLysM-1 protein was predicted to be an intracellular non-secreted LysM-containing protein, highly homologous to the same protein in other marine echinoderms. AjLysM-1 transcripts were highest expressed in coelomocytes and were strikingly induced by challenge with representative bacterial and fungal polysaccharides. rAjLysM-1 showed weak binding to mannan, Pseudoalteromonas nigrifaciens, and Shewanella baltica, implying that AjLysM-1 might provide inadequate defense against Gram-negative bacteria and fungi. Notably, rAjLysM-1 also interacted with tyrosine protein kinase and filamin-B, indicating that it could be involved in focal adhesion in A. japonicus. These findings improve our understanding of the functions of LysM-containing proteins in marine echinoderms.


Asunto(s)
Pepinos de Mar , Stichopus , Animales , Pepinos de Mar/genética , ADN Complementario/genética , ADN Complementario/metabolismo , Proteínas Recombinantes/metabolismo , Antibacterianos/metabolismo , Inmunidad Innata/genética
15.
Fish Shellfish Immunol ; 128: 67-73, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35921931

RESUMEN

The sea cucumber Apostichopus japonicus is one of the most dominant and economically important aquaculture species in China. Saponin, which possesses notable biological and pharmacological properties, is a key determinant of the nutritional and health value of A. japonicus. In the present study, we amplified the full-length cDNA of a phosphomevalonate kinase (PMK) gene (named AjPMK) using rapid amplification of cDNA ends (RACE). Subsequently, we engineered a recombinant AjPMK (rAjPMK) protein and assessed its enzymatic activity by enzyme-linked immunosorbent assay (ELISA). Proteins that interact with rAjPMK were screened and identified via pull-down assay combined with liquid chromatography with tandem mass spectrometry (LC-MS/MS). We found that the full-length cDNA of AjPMK contained 1354 bp and an open reading frame (ORF) of 612 bp. The AjPMK protein was predicted not to contain a signal peptide but to contain a phosphonolate kinase domain seen in higher eukaryotes and a P-loop with a relatively conserved nucleoside triphosphate hydrolase domain. The molecular weight of the AjPMK protein was estimated to be 23.81 kDa, and its isoelectric point was predicted to be 8.72. Phylogenetic analysis showed that AjPMK had a closer evolutionary relationship with genes from starfish than with those of other selected species. Besides, we found that rAjPMK synthesized mevalonate-5-diphosphate, interacted either directly or indirectly with crucial pattern recognition receptors (PRRs) and was regulated by immune-related processes, including antioxidative reactions, stress resistance responses and enzyme hydrolysis. Moreover, AjPMK also interacted with farnesyl pyrophosphate synthase, an enzyme reported to be involved in saponin biosynthesis. Together, our findings implied that AjPMK may be directly involved in saponin biosynthesis and the regulation of various innate immune processes.


Asunto(s)
Saponinas , Pepinos de Mar , Stichopus , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Cromatografía Liquida , Clonación Molecular , ADN Complementario/genética , ADN Complementario/metabolismo , Difosfatos , Hidrolasas/genética , Hidrolasas/metabolismo , Inmunidad Innata/genética , Ácido Mevalónico/análogos & derivados , Nucleósidos , Fosfotransferasas (Aceptor del Grupo Fosfato) , Filogenia , Señales de Clasificación de Proteína/genética , Pepinos de Mar/genética , Espectrometría de Masas en Tándem
16.
Materials (Basel) ; 15(11)2022 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-35683320

RESUMEN

A simple and efficient approach for the high-purity CaSO4·2H2O (DH) whiskers and α-CaSO4·0.5H2O (α-HH) whiskers derived from such phosphogypsum (PG) was proposed. The impact of different experimental parameters on supersaturated dissolution-recrystallization and preparation processes of α-CaSO4·0.5H2O was elaborated. At 3.5 mol/L HCl concentration, the dissolution temperature and time were 90 °C and 20 min, respectively. After eight cycles and 5-8 times cycles, total crystallization amount of CaSO4·2H2O was 21.75 and 9.97 g/100 mL, respectively, from supersaturated HCl solution. The number of cycles affected the shape and amount of the crystal. Higher HCl concentration facilitated CaSO4·2H2O dissolution and created a much higher supersaturation, which acted as a larger driving force for phase transformation of CaSO4·2H2O to α-CaSO4·0.5H2O. The HCl solution system's optimum experimental conditions for HH whiskers preparation involved acid leaching of CaSO4·2H2O sample, with HCl concentration 6.0 mol/L, reaction temperature 80 °C, and reaction time 30 min-60 min. Under the third cycle conditions, α-CaSO4·0.5H2O whiskers were uniform in size, clear, and distinct in edges and angles. The length range of α-CaSO4·0.5H2O whiskers was from 106 µm to 231 µm and diameter range from 0.43 µm to 1.35 µm, while the longest diameter ratio was 231. Purity of α-CaSO4·0.5H2O whiskers was approximately 100%, where whiteness reached 98.6%. The reuse of the solution enables the process to discharge no waste liquid. It provides a new reference direction for green production technology of phosphogypsum.

17.
Front Chem ; 10: 839680, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35372276

RESUMEN

The direct sintering process of coal fly ash for the preparation of glass-ceramics is the liquid-phase sintering process, from non-densification to densification. When the temperature exceeds the densification temperature point, the porosity of glass-ceramics on the contrary increases and the pore diameter increases. This provides a basis to prepare porous glass-ceramics by direct overfiring. Adding borax to coal fly ash can reduce the temperature of liquid phase formation, reduce the preparing temperature of porous glass-ceramics, achieve the purpose of energy saving. The effects of borax on the structure, properties and sintering kinetics of porous glass-ceramics prepared from coal fly ash by overfiring were investigated. It is found that the introduction of B-O bond can change the network structure of non-crystalline vitreous in coal fly ash, reduce the melting temperature, promote the formation of liquid phase, and thus increase the porosity of porous glass-ceramics. This paper provides a certain experimental basis for the preparation of porous glass-ceramics by direct overfiring of coal fly ash at low temperature without adding pore-forming agent, and provides a new possibility for the high-value resource utilization of coal fly ash.

18.
Environ Microbiol ; 24(9): 3882-3897, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35297145

RESUMEN

Nowadays, the true economic and nutritional value of food is underpinned by both origin and quality traits, more often expressed as increased quality benefits derived from the origin source. Gut microbiota contribute to food metabolism and host health, therefore, it may be suitable as a qualifying indicator of origin and quality of economic species. Here, we investigated relationships between the gut microbiota of the sea cucumber (Apostichopus japonicus), a valuable aquaculture species in Asia, with their origins and quality metrics. Based on data from 287 intestinal samples, we generated the first biogeographical patterns for A. japonicus gut microbiota from origins across China. Importantly, A. japonicus origins were predicted using the random forest model that was constructed using 20 key gut bacterial genera, with 97.6% accuracy. Furthermore, quality traits such as saponin, fat and taurine were also successfully predicted by random forest models based on gut microbiota, with approximately 80% consistency between predicted and true values. We showed that substantial variations existed in the gut microbiota and quality variables in A. japonicus across different origins, and we also demonstrated the great potential of gut microbiota to track A. japonicus origins and predict their quality traits.


Asunto(s)
Microbioma Gastrointestinal , Saponinas , Pepinos de Mar , Stichopus , Animales , Stichopus/microbiología , Taurina
19.
Artículo en Inglés | MEDLINE | ID: mdl-35055438

RESUMEN

Non-biodegradable copper (Cu) and lead (Pb) contaminants in water are highly toxic and have series adverse effects. Therefore, it is very important to extract heavy metals from wastewater before it is discharged into the environment. Adsorption is a cost-effective alternative method for wastewater treatment. Choosing a low-cost adsorbent can help reduce the cost of adsorption. In this study, conversion of reside after extracting aluminum (REA) produced by sub-molten salt method transform high-alumina coal fly ash (CFA) into 11Å-tobermorite to adsorb Cu(II) and Pb(II) from aqueous solutions at room temperature. The synthesis of the adsorbent was confirmed using scanning electron microscope (SEM), X-ray diffractometer (XRD) and Brunauer-Emmett-Teller (BET) method surface analysis. To study the adsorption characteristics, factors such as initial Cu(II) and Pb(II) concentration, pH, contact time, adsorption characteristics and temperature were investigated in batch mode. The maximum adsorption capacity of Cu(II) and Pb(II) was 177.1 mg·g-1 and 176.2 mg·g-1, respectively. The Langmuir adsorption model was employed to better describe the isothermal adsorption behavior and confirm the monolayer adsorption phenomenon. The pseudo-second-order kinetic model was used to highlight Cu(II) and Pb(II) adsorption kinetics. Thermodynamic analysis indicated the removal Cu(II) and Pb(II) by TA-adsorbent was a nonspontaneous and exothermic reaction. The obtained results are of great significance to the conversion of industrial waste to low-cost adsorbent for Cu(II) and Pb(II) removal from water.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , Adsorción , Óxido de Aluminio , Carbón Mineral , Ceniza del Carbón , Concentración de Iones de Hidrógeno , Iones , Cinética , Plomo , Agua
20.
Materials (Basel) ; 16(1)2022 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-36614572

RESUMEN

Preparing ceramic materials is a meaningful way to treat and utilize industrial slags. In this work, high-performance and low-deformation industrial slag ceramics were prepared from Ti-extraction blast furnace slag and illitic clay. The phase composition and contents, microstructure, physical properties, and pyroplastic deformation of ceramic samples were investigated. With the increasing proportion of illitic clay, the main crystalline phase of ceramic samples changed from akermanite to Fe-bearing diopside. Moreover, the minor crystalline phases changed from perovskite and spinel to anorthite and titanite. The proportion of illitic clay was linearly related to the amorphous phase content. The dense microstructure comprised concentrated short-columnar and granular grains with a few isolated pores, whereas plate-like grains destroyed their denseness. An appropriate proportion of illitic clay helped to improve the physical properties, increase the high-temperature viscosity and reduce the deformation of the ceramics. The optimal proportion of illitic clay was 30%, and the prepared ceramic sample had a dense microstructure and excellent physical properties. Its bulk density was 2.82 g/cm3, bending strength was 62.17 MPa, and water absorption was 0.21%.

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