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1.
Sci Rep ; 14(1): 10798, 2024 05 11.
Article in English | MEDLINE | ID: mdl-38734777

ABSTRACT

The nucleation of carbonate-containing apatite on the biomaterials surface is regarded as a significant stage in bone healing process. In this regard, composites contained hydroxyapatite (Ca10(PO4)6(OH)2, HA), wollastonite (CaSiO3, WS) and polyethersulfone (PES) were synthesized via a simple solvent casting technique. The in-vitro bioactivity of the prepared composite films with different weight ratios of HA and WS was studied by placing the samples in the simulated body fluid (SBF) for 21 days. The results indicated that the the surface of composites containing 2 wt% HA and 4 wt% WS was completely covered by a thick bone-like apatite layer, which was characterized by Grazing incidence X-ray diffraction, attenuated total reflectance-Fourier transform infrared spectrometer, field emission electron microscopy and energy dispersive X-ray analyzer (EDX). The degradation study of the samples showed that the concentration of inorganic particles could not influence the degradability of the polymeric matrix, where all samples expressed similar dexamethasone (DEX) release behavior. Moreover, the in-vitro cytotoxicity results indicated the significant cyto-compatibility of all specimens. Therefore, these findings revealed that the prepared composite films composed of PES, HA, WS and DEX could be regarded as promising bioactive candidates with low degradation rate for bone tissue engineering applications.


Subject(s)
Biocompatible Materials , Bone Substitutes , Durapatite , Nanocomposites , Silicates , Durapatite/chemistry , Nanocomposites/chemistry , Bone Substitutes/chemistry , Bone Substitutes/pharmacology , Silicates/chemistry , Biocompatible Materials/chemistry , Calcium Compounds/chemistry , Drug Liberation , Dexamethasone/chemistry , Dexamethasone/pharmacology , Polymers/chemistry , Humans , X-Ray Diffraction , Materials Testing , Spectroscopy, Fourier Transform Infrared , Animals
2.
Luminescence ; 39(5): e4750, 2024 May.
Article in English | MEDLINE | ID: mdl-38733198

ABSTRACT

Ultra-high thermally stable Ca2MgWO6:xSm3+ (x = 0.5, 0.75, 1, 1.25, and 1.5 mol%) double perovskite phosphors were synthesized through solid-state reaction method. Product formation was confirmed by comparing the X-ray diffraction (XRD) patterns of the phosphors with the standard reference file. The structural, morphological, thermal, and optical properties of the prepared phosphor were examined in detail using XRD, Fourier transform infrared spectra, scanning electron microscopy, diffused reflectance spectra, thermogravimetric analysis (TGA), photoluminescence emission, and temperature-dependent PLE (TDPL). It was seen that the phosphor exhibited emission in the reddish region for the near-ultraviolet excitation with moderate Colour Rendering Index values and high colour purity. The optimized phosphor (x = 1.25 mol%) was found to possess a direct optical band gap of 3.31 eV. TGA studies showed the astonishing thermal stability of the optimized phosphor. Additionally, near-zero thermal quenching was seen in TDPL due to elevated phonon-assisted radiative transition. Furthermore, the anti-Stokes and Stokes emission peaks were found to be sensitive toward the temperature change and followed a Boltzmann-type distribution. All these marked properties will make the prepared phosphors a suitable candidate for multifield applications and a fascinating material for further development.


Subject(s)
Luminescence , Luminescent Agents , Samarium , Temperature , Tungsten Compounds , Tungsten Compounds/chemistry , Luminescent Agents/chemistry , Luminescent Agents/chemical synthesis , Samarium/chemistry , Luminescent Measurements , X-Ray Diffraction , Calcium Compounds/chemistry , Oxides/chemistry , Thermogravimetry
3.
J Environ Sci (China) ; 144: 212-224, 2024 Oct.
Article in English | MEDLINE | ID: mdl-38802232

ABSTRACT

In this work, the perovskite LaZnO3 was synthesized via sol-gel method and applied for photocatalytic treatment of sulfamethizole (SMZ) antibiotics under visible light activation. SMZ was almost completely degraded (99.2% ± 0.3%) within 4 hr by photocatalyst LaZnO3 at the optimal dosage of 1.1 g/L, with a mineralization proportion of 58.7% ± 0.4%. The efficient performance of LaZnO3 can be attributed to its wide-range light absorption and the appropriate energy band edge levels, which facilitate the formation of active agents such as ·O2-, h+, and ·OH. The integration of RP-HPLC/Q-TOF-MS and DFT-based computational techniques revealed three degradation pathways of SMZ, which were initiated by the deamination reaction at the aniline ring, the breakdown of the sulfonamide moieties, and a process known as Smile-type rearrangement and SO2 intrusion. Corresponding toxicity of SMZ and the intermediates were analyzed by quantitative structure activity relationship (QSAR), indicating the effectiveness of LaZnO3-based photocatalysis in preventing secondary pollution of the intermediates to the ecosystem during the degradation process. The visible-light-activated photocatalyst LaZnO3 exhibited efficient performance in the occurrence of inorganic anions and maintained high durability across multiple recycling tests, making it a promising candidate for practical antibiotic treatment.


Subject(s)
Anti-Bacterial Agents , Light , Oxides , Sulfamethizole , Titanium , Water Pollutants, Chemical , Anti-Bacterial Agents/chemistry , Titanium/chemistry , Oxides/chemistry , Sulfamethizole/chemistry , Water Pollutants, Chemical/chemistry , Calcium Compounds/chemistry , Catalysis , Photolysis , Models, Chemical
4.
Sci Total Environ ; 934: 173296, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-38761950

ABSTRACT

This study explored the redox-mediated changes in a lead (Pb) contaminated soil (900 mg/kg) due to the addition of solar cell powder (SC) and investigated the impact of biochar derived from soft wood pellet (SWP) and oil seed rape straw (OSR) (5% w/w) on Pb immobilization using an automated biogeochemical microcosm system. The redox potential (Eh) of the untreated (control; SC) and biochar treated soils (SC + SWP and SC + OSR) ranged from -151 mV to +493 mV. In SC, the dissolved Pb concentrations were higher under oxic (up to 2.29 mg L-1) conditions than reducing (0.13 mg L-1) conditions. The addition of SWP and OSR to soil immobilized Pb, decreased dissolved concentration, which could be possibly due to the increase of pH, co-precipitation of Pb with FeMn (hydro)oxides and pyromorphite, and complexation with biochar surface functional groups. The ability and efficiency of OSR for Pb immobilization were higher than SWP, owing to the higher pH and density of surface functional groups of OSR than SWP. Biochar enhanced the relative abundance of Proteobacteria irrespective of Eh changes, while the relative abundance of Bacteroidota increased under oxidizing conditions. Overall, we found that both OSR and SWP immobilized Pb in solar panel waste contaminated soil under both oxidizing and reducing redox conditions which may mitigate the potential risk of Pb contamination.


Subject(s)
Calcium Compounds , Charcoal , Lead , Oxidation-Reduction , Soil Microbiology , Soil Pollutants , Lead/analysis , Charcoal/chemistry , Soil Pollutants/analysis , Calcium Compounds/chemistry , Oxides/chemistry , Titanium/chemistry , Soil/chemistry , Bacteria
5.
Environ Pollut ; 351: 124063, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38697254

ABSTRACT

Soil stabilization/solidification is commonly employed remediation method for contaminated soils. Until now, limited attention has been given to the application of quicklime in polycyclic aromatic hydrocarbons (PAHs) contaminated soil. We treated a tectogenic industriosol spiked with 50 mg kg-1 of four PAHs (12.5 mg kg-1 each of fluorene (FLU), phenanthrene (PHE), fluoranthene (FLT) and pyrene (PYR)) using three different liming agents at 1% (w:w): quicklime (CaO), hydrated lime (Ca(OH)2) and carbonate calcium (CaCO3). All treated samples were leached in water at a solid-liquid ratio of 10, with subsequent analysis of leached soil and leachates for PAHs content. Results revealed that the addition of liming agents led to a reduction in FLU and PHE concentrations in treated soil by 6.81 ± 2.47% and 28.88 ± 4.18%, respectively, compared to a not-treated sol. However, no significant impact was observed on the 4-cycles PAHs (FLT and PYR). The addition of liming agents also significantly decreased the amount of PAHs in the leachate, by 100% for FLU and PHE, and by 74.9 ± 17.5% and 72.3 ± 34.8%, for FLT and PYR, respectively, compared to not limed soil. Among the liming agents, quicklime was the most effective in reducing the amount of 4 cycles PAHs in the leachate. Various mechanisms, such as encapsulation, volatilization and oxidation could contribute to this observed reduction. Quicklime treatment at a concentration of 1% w:w in PAHs-contaminated soil emerges as a promising technique to effectively reduce PAHs concentration in soils and mitigate PAHs mobility through leaching. This study also sheds light on the possibility to limit CO2 emissions and resources exploitation to assure the remediation process, thereby enhancing its overall environmental sustainability.


Subject(s)
Calcium Compounds , Environmental Restoration and Remediation , Oxides , Polycyclic Aromatic Hydrocarbons , Soil Pollutants , Polycyclic Aromatic Hydrocarbons/analysis , Calcium Compounds/chemistry , Oxides/chemistry , Environmental Restoration and Remediation/methods , Soil/chemistry , Fluorenes , Phenanthrenes/chemistry
6.
Environ Sci Pollut Res Int ; 31(24): 34881-34895, 2024 May.
Article in English | MEDLINE | ID: mdl-38714613

ABSTRACT

The structural, mechanical, vibrational, electronic, optical, SLME, thermoelectric, and thermodynamic properties of X2GaAgCl6 (X = Cs, Rb), a double perovskite material, were computed by employing Density Functional Theory (DFT). CASTEP and Quantum ESPRESSO were used to perform first-principles calculations. X2GaAgCl6 possesses a cubic structure with the space-group symmetry Fm-3 m. The lattice parameters of Cs2GaAgCl6 and Rb2GaAgCl6 were optimized using the energy-volume curves, resulting in values of 7.357 Å and 7.365 Å, respectively. The population analysis confirmed the charge transfer among transition metals and halogen atoms. The stability of crystal X2GaAgCl6 (X = Cs, Rb) is effectively demonstrated by analyzing phonon dispersion curves with no negative frequencies. The band structure calculations indicated the semiconducting nature of compounds with energy gaps of 0.96 eV and 0.88 eV for Cs2GaAgCl6 and Rb2GaAgCl6, respectively. The optical characteristics results confirm that the examined materials are suitable for devices working, primarily in the electromagnetic spectrum's visible region. SLME results showed that Cs2GaAgCl6 has 30% and Rb2GaAgCl6 has 27% efficiency, respectively, suggesting their use in photovoltaics. The thermoelectric properties of X2GaAgCl6 (X = Cs, Rb) were calculated by using the BoltzTraP code in the temperature range of 300 to 800 K. The quasi-harmonic Debye model was applied to calculate the thermodynamic characteristics.


Subject(s)
Calcium Compounds , Solar Energy , Thermodynamics , Titanium , Titanium/chemistry , Calcium Compounds/chemistry , Oxides/chemistry
7.
PeerJ ; 12: e17237, 2024.
Article in English | MEDLINE | ID: mdl-38699192

ABSTRACT

Background: Root perforation repair presents a significant challenge in dentistry due to inherent limitations of existing materials. This study explored the potential of a novel polydopamine-based composite as a root repair material by evaluating its sealing efficacy, radiopacity, and surface topography. Methods: Confocal microscopy assessed sealing ability, comparing the polydopamine-based composite to the gold standard, mineral trioxide aggregate (MTA). Radiopacity was evaluated using the aluminium step wedge technique conforming to ISO standards. Surface roughness analysis utilized atomic force microscopy (AFM), while field emission scanning electron microscopy (FESEM) visualized morphology. Results: The polydopamine-based composite exhibited significantly superior sealing efficacy compared to MTA (P < 0.001). Radiopacity reached 3 mm aluminium equivalent, exceeding minimum clinical requirements. AFM analysis revealed a smooth surface topography, and FESEM confirmed successful composite synthesis. Conclusion: This study demonstrates promising properties of the polydopamine-based composite for root perforation repair, including superior sealing efficacy, clinically relevant radiopacity, and smooth surface topography. Further investigation is warranted to assess its clinical viability and potential translation to endodontic practice.


Subject(s)
Aluminum Compounds , Calcium Compounds , Indoles , Oxides , Polymers , Root Canal Filling Materials , Silicates , Surface Properties , Polymers/chemistry , Indoles/chemistry , Silicates/chemistry , Calcium Compounds/chemistry , Oxides/chemistry , Root Canal Filling Materials/chemistry , Aluminum Compounds/chemistry , Humans , Drug Combinations , Microscopy, Electron, Scanning , Microscopy, Atomic Force/methods , Microscopy, Confocal , Materials Testing , Tooth Root/injuries , Tooth Root/diagnostic imaging , Tooth Root/surgery
8.
Chemosphere ; 358: 142237, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38705406

ABSTRACT

In this study, a novel Ce2MgMoO6/CNFs (cerium magnesium molybdite double perovskite decorated on carbon nanofibers) nanocomposite was developed for selective and ultra-sensitive detection of ciprofloxacin (CFX). Physical characterization and analytical techniques were used to explore the morphology, structure, and electrocatalytic characteristics of the Ce2MgMoO6/CNFs nanocomposite. The sensor has a wide linear range (0.005-7.71 µM and 9.75-77.71 µM), a low limit of detection (0.012 µM), high sensitivity (0.807 µA µM-1 cm-2 nM), remarkable repeatability, and an appreciable storage stability. Here, we used density functional theory to investigate CFX and oxidized CFX as well as the locations of the energy levels and electron transfer sites. Furthermore, the Ce2MgMoO6/CNFs-modified electrode was successfully tested in food samples (milk and honey), indicating an acceptable response with a recovery percentage and relative standard deviation of less than 4%, which is comparable to that of GC-MS. Finally, the developed sensor exhibited high selectivity and stability for CFX detection.


Subject(s)
Carbon , Ciprofloxacin , Honey , Milk , Nanocomposites , Nanofibers , Oxides , Nanocomposites/chemistry , Ciprofloxacin/analysis , Ciprofloxacin/chemistry , Oxides/chemistry , Milk/chemistry , Nanofibers/chemistry , Animals , Honey/analysis , Carbon/chemistry , Molybdenum/chemistry , Limit of Detection , Calcium Compounds/chemistry , Titanium/chemistry , Density Functional Theory , Electrochemical Techniques/methods , Cerium/chemistry , Food Contamination/analysis , Electrodes , Magnesium/chemistry , Magnesium/analysis
9.
Mikrochim Acta ; 191(6): 316, 2024 05 10.
Article in English | MEDLINE | ID: mdl-38724679

ABSTRACT

An ultra-sensitive photoelectrochemical (PEC) sensor based on perovskite composite was developed for the determination of alkaline phosphatase (ALP) in human serum. In contrast to CsPbBr3 or Y6 that generated anodic current, the heterojunction of CsPbBr3/Y6 promoted photocarriers to separate and generated cathodic photocurrent. Ascorbic acid (AA) was produced by ALP hydrolyzing L-ascorbic acid 2-phosphate trisodium salt (AAP), which can combine with the holes on the photoelectrode surface, accelerating the transmission of photogenerated carriers, leading to enhanced photocurrent intensity. Thus, the enhancement of PEC current was linked to ALP activity. The PEC sensor exhibits good sensitivity for detection of ALP owing to the unique photoelectric properties of the CsPbBr3/Y6 heterojunction. The detection limit of the sensor was 0.012 U·L-1 with a linear dynamic range of 0.02-2000 U·L-1. Therefore, this PEC sensing platform shows great potential for the development of different PEC sensors.


Subject(s)
Alkaline Phosphatase , Ascorbic Acid , Electrochemical Techniques , Electrodes , Limit of Detection , Oxides , Photochemical Processes , Titanium , Alkaline Phosphatase/chemistry , Alkaline Phosphatase/blood , Alkaline Phosphatase/metabolism , Humans , Electrochemical Techniques/methods , Electrochemical Techniques/instrumentation , Ascorbic Acid/chemistry , Ascorbic Acid/blood , Ascorbic Acid/analogs & derivatives , Titanium/chemistry , Oxides/chemistry , Calcium Compounds/chemistry , Biosensing Techniques/methods
10.
Anal Methods ; 16(18): 2857-2868, 2024 May 09.
Article in English | MEDLINE | ID: mdl-38639051

ABSTRACT

The pentavalent arsenic compound roxarsone (RSN) is used as a feed additive in poultry for rapid growth, eventually ending up in poultry litter. Poultry litter contains chicken manure, which plays a vital role as an affordable fertilizer by providing rich nutrients to agricultural land. Consequently, the extensive use of poultry droppings serves as a conduit for the spread of toxic forms of arsenic in the soil and surface water. RSN can be easily oxidized to release highly carcinogenic As(III) and As(IV) species. Thus, investigations were conducted for the sensitive detection of RSN electrochemically by developing a sensor material based on lanthanum manganese oxide (LMO) and functionalized carbon nanofibers (f-CNFs). The successfully synthesised LMO/f-CNF composite was confirmed by chemical, compositional, and morphological studies. The electrochemical activity of the prepared composite material was examined using cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The obtained results confirmed that LMO/f-CNF showed enhanced electrocatalytic activity and improved current response with a good linear range (0.01-0.78 µM and 2.08-497 µM, respectively), exhibiting a low limit of detection (LOD) of 0.004 µM with a high sensitivity of 13.24 µA µM-1 cm-2 towards the detection of RSN. The noteworthy features of LMO/f-CNF composite with its superior electrochemical performance enabled reliable reproducibility, exceptional stability and reliable practical application in the analysis of tap water and food sample, affording a recovery range of 86.1-98.87%.


Subject(s)
Calcium Compounds , Electrochemical Techniques , Lanthanum , Nanofibers , Oxides , Roxarsone , Titanium , Nanofibers/chemistry , Lanthanum/chemistry , Oxides/chemistry , Electrochemical Techniques/methods , Roxarsone/chemistry , Roxarsone/analysis , Titanium/chemistry , Calcium Compounds/chemistry , Water Pollutants, Chemical/analysis , Carbon/chemistry , Limit of Detection , Food Analysis/methods , Food Contamination/analysis , Animals , Manganese Compounds/chemistry
11.
Braz Oral Res ; 38: e028, 2024.
Article in English | MEDLINE | ID: mdl-38597547

ABSTRACT

Acidic pH can modify the properties of repair cements. In this study, volumetric change and solubility of the ready-to-use bioceramic repair cement Bio-C Repair (BCR, Angelus, Londrina, PR, Brazil) were evaluated after immersion in phosphate-buffered saline (PBS) (pH 7.0) or butyric acid (pH 4.5). Solubility was determined by the difference in initial and final mass using polyethylene tubes measuring 4 mm high and 6.70 mm in internal diameter that were filled with BCR and immersed in 7.5 mL of PBS or butyric acid for 7 days. The volumetric change was established by using bovine dentin tubes measuring 4 mm long with an internal diameter of 1.5 mm. The dentin tubes were filled with BCR at 37°C for 24 hours. Scanning was performed with micro-computed tomography (micro-CT; SkyScan 1176, Bruker, Kontich, Belgium) with a voxel size of 8.74 µm. Then, the specimens were immersed in 1.5 mL of PBS or butyric acid at and 37 °C for 7 days. After this period, a new micro-CT scan was performed. Bio-C Repair showed greater mass loss after immersion in butyric acid when compared with immersion in PBS (p<0.05). Bio-C Repair showed volumetric loss after immersion in butyric acid and increase in volume after immersion in PBS (p<0.05). The acidic pH influenced the solubility and dimensional stability of the Bio-C Repair bioceramic cement, promoting a higher percentage of solubility and decrease in volumetric values.


Subject(s)
Oxides , Root Canal Filling Materials , Animals , Cattle , Solubility , Oxides/chemistry , Calcium Compounds/chemistry , X-Ray Microtomography , Butyric Acid , Materials Testing , Dental Cements/chemistry , Glass Ionomer Cements , Hydrogen-Ion Concentration , Silicates/chemistry , Root Canal Filling Materials/chemistry
12.
Luminescence ; 39(5): e4754, 2024 May.
Article in English | MEDLINE | ID: mdl-38679894

ABSTRACT

Near-infrared mechanoluminescence is a phenomenon that produces high penetrating near-infrared light under external stimulation. Near-infrared light coincides with the biological window, lower optical loss, and the fact that the mechanoluminescence material is a medium that converts mechanical energy into light energy. The near-infrared mechanoluminescence material has potential application prospects in the fields of biological imaging, medical diagnosis, and monitoring of building materials. In this article, we report on a perovskite-type Sr3Sn2O7:Nd3+ near-infrared mechanoluminescence material, and its peaks locate in the first near-infrared window (800-1000 nm) and the second near-infrared window (1080, 1350 nm), respectively. Under the condition of pre-sintering with Li2CO3 as flux, the best sintering conditions are obtained, and the luminescence of material is in perfect agreement with the applied mechanical stress. In addition, a near-infrared mechanoluminescence sensor is proposed to solve the problem of building damage and timely maintenance.


Subject(s)
Infrared Rays , Luminescent Measurements , Titanium , Luminescence , Oxides/chemistry , Strontium/chemistry , Neodymium/chemistry , Calcium Compounds/chemistry
13.
Biosens Bioelectron ; 256: 116275, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-38603839

ABSTRACT

Constructing relatively inexpensive nanomaterials to simulate the catalytic performance of laccase is of great significance in recent years. Although research on improving laccase-like activity by regulating ligands of copper (amino acids or small organic molecules, etc.) have achieved remarkable success. There are few reports on improving laccase-like activity by adjusting the composition of metal Cu. Here, we used perovskite hydroxide AB(OH)6 as a model to evaluate the relationship between Cu based alloys and their laccase-like activity. We found that when the Cu/Mn alloy ratio of the perovskite hydroxide A point is greater than 1, the laccase-like activity of the binary alloy perovskite hydroxide is higher than that of the corresponding single Cu. Based on the measurements of XPS and ICP-MS, we deduced that the improvements of laccase-like activity mainly attribute to the ratio of Cu+/Cu2+and the content of Cu. Moreover, two types of substrates (toxic pollutants and catechol neurotransmitters) were used to successfully demonstrated such nanozymes' excellent environmental protecting function and biosensing property. This work will provide a novel approach for the construction and application of laccase-like nanozymes in the future.


Subject(s)
Biosensing Techniques , Copper , Laccase , Oxides , Titanium , Laccase/chemistry , Laccase/metabolism , Biosensing Techniques/methods , Copper/chemistry , Titanium/chemistry , Oxides/chemistry , Hydroxides/chemistry , Calcium Compounds/chemistry , Environmental Restoration and Remediation/methods , Catechols/analysis , Catechols/chemistry , Biomimetic Materials/chemistry , Catalysis
14.
Int J Biol Macromol ; 267(Pt 1): 131580, 2024 May.
Article in English | MEDLINE | ID: mdl-38688788

ABSTRACT

Despite the clinical success of tricalcium silicate (TCS)-based materials in endodontics, the inferior handling characteristic, poor anti-washout property and slow setting kinetics hindered their wider applications. To solve these problems, an injectable fast-setting TCS/ß-tricalcium phosphate/monocalcium phosphate anhydrous (ß-TCP/MCPA) cement was developed for the first time by incorporation of hydroxypropyl methylcellulose (HPMC) and ß-TCP/MCPA. The physical-chemical characterization (setting time, anti-washout property, injectability, compressive strength, apatite mineralization and sealing property) of TCS/(ß-TCP/MCPA) were conducted. Its hydration mechanism was also investigated. Furthermore, the cytocompatibility and osteogenic/odontogenic differentiation of stem cells isolated from human exfoliated deciduous teeth (SHED) treated with TCS/ß-TCP/MCPA were studied. The results showed that HPMC could provide TCS with good anti-washout ability and injectability but slow hydration process. However, ß-TCP/MCPA effectively enhanced anti-washout characteristics and reduced setting time due to faster hydration kinetics. TCS/(ß-TCP/MCPA) obtained around 90 % of injection rate and high compressive strength whereas excessive additions of ß-TCP/MCPA compromised its injectability and compressive strength. TCS/(ß-TCP/MCPA) can induce apatite deposition and form a tight marginal sealing at the dentin-cement interface. Additionally, TCS/(ß-TCP/MCPA) showed good biocompatibility and promoted osteo/odontogenic differentiation of SHED. In general, our results indicated that TCS/(ß-TCP/MCPA) may be particularly promising as an injectable bioactive cements for endodontic treatment.


Subject(s)
Calcium Compounds , Calcium Phosphates , Hypromellose Derivatives , Silicates , Silicates/chemistry , Calcium Phosphates/chemistry , Calcium Phosphates/pharmacology , Calcium Compounds/chemistry , Humans , Hypromellose Derivatives/chemistry , Osteogenesis/drug effects , Materials Testing , Cell Differentiation/drug effects , Compressive Strength , Biocompatible Materials/chemistry , Biocompatible Materials/pharmacology , Dental Cements/chemistry , Dental Cements/pharmacology , Stem Cells/drug effects , Stem Cells/cytology
15.
J Mech Behav Biomed Mater ; 155: 106559, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38657285

ABSTRACT

Additive Manufacturing (AM) enables the generation of complex geometries and controlled internal cavities that are so interesting for the biomedical industry due to the benefits they provide in terms of osseointegration and bone growth. These technologies enable the manufacturing of the so-called lattice structures that are cells with different geometries and internal pores joint together for the formation of scaffold-type structures. In this context, the present paper analyses the feasibility of using diamond-type lattice structures and topology optimisation for the re-design of a dental implant. Concretely, a new ultra-short implant design is proposed in this work. For the manufacturing of the implant, digital light processing additive manufacturing technique technology is considered. The implant was made out of Nano-zirconia and Nano-Calcium Silicate as an alternative material to the more common Ti6Al4V. This material combination was selected due to the properties of the calcium-silicate that enhance bone ingrowth. The influence of different material combination ratios and lattice pore sizes were analysed by means of FEM simulation. For those simulations, a bio-material bone-nanozirconia model was considered that represents the final status after the bone is integrated in the implant. Results shows that the mechanical properties of the biocompatible composite employed were suitable for dental implant applications in dentistry. Based on the obtained results it was seen that those designs with 400 µm and 500 µm pore sizes showed best performance and led to the required factor of safety.


Subject(s)
Calcium Compounds , Dental Implants , Printing, Three-Dimensional , Silicates , Zirconium , Zirconium/chemistry , Silicates/chemistry , Calcium Compounds/chemistry , Finite Element Analysis , Materials Testing , Porosity , Mechanical Phenomena
16.
Int J Biol Macromol ; 268(Pt 1): 131535, 2024 May.
Article in English | MEDLINE | ID: mdl-38631586

ABSTRACT

Herein, efficient degradation of hexabromocyclododecane (HBCD) and Lindane, a persistent organic pollutant using guar gum based calcium oxide doped silicon dioxide (GG-CaO@SiO2) has been reported. The nanocomposite was prepared by waste egg shell (CaO) and rice husk (SiO2) was well characterized. The maximum degradation of HBCD and Lindane were observed at 8 mg catalyst loading, neutral pH, and 2 mg L-1 of pollutant amount. The photocatalytic performance of GG-CaO@SiO2 for HBCD and Lindane photodegradation was evaluated, and it was found that the rate constant increased in the order of GG-CaO@SiO2 > CaO@SiO2 > GG. The polymeric GG-CaO@SiO2 nanocomposite showed maximum removal of both pollutants due to higher surface area (70 m2 g-1) and synergistic interactions among GG moieties. It achieved HBCD and Lindane elimination rates of 94 % and 90 % by photo-adsorptive degradation within 150 min. Meanwhile, the leaching of HBCD from expanded polystyrene (EPS) materials (0.14 ± 0.05 ppm) underwater with different time intervals and degradation of leachate HBCD were also assessed. The eradication of the pollutant manifested first-order kinetics, with the Langmuir adsorption. LC-MS analysis confirmed that GG-CaO@SiO2 effectively breaks down complex structure toxic pollutants into safer metabolites under natural sunlight exposure. The polymeric GG-CaO@SiO2 nanocomposite showed notable reusability up to ten cycle promotes sustainability.


Subject(s)
Galactans , Hexachlorocyclohexane , Mannans , Nanocomposites , Plant Gums , Plant Gums/chemistry , Mannans/chemistry , Nanocomposites/chemistry , Galactans/chemistry , Hexachlorocyclohexane/chemistry , Silicon Dioxide/chemistry , Water Pollutants, Chemical/chemistry , Water Pollutants, Chemical/isolation & purification , Calcium Compounds/chemistry , Oxides/chemistry , Photolysis , Adsorption , Waste Products , Catalysis , Hydrogen-Ion Concentration , Hydrocarbons, Brominated
17.
Environ Sci Pollut Res Int ; 31(21): 30959-30971, 2024 May.
Article in English | MEDLINE | ID: mdl-38619769

ABSTRACT

Soil amendment is an important strategy for improving soil quality and crop yield. From 2014 to 2019, we conducted a study to investigate the effects of tobacco straw return with lime on soil nutrients, soil microbial community structure, tobacco leaf yield, and quality in southern Anhui, China. A field experiment was conducted with four treatments: straw removed (CK), straw return (St), straw return with dolomite (St + D), and straw return with lime (St + L). Results showed that after 5 years of application, the St + L significantly increased the soil pH by 16.9%, and the contents of soil alkaline nitrogen (N) and available potassium (K) by 17.2% and 23.0%, respectively, compared with the CK. Moreover, the St + L significantly increased tobacco leaf yield (24.0%) and the appearance (9.1%) and sensory (5.9%) quality of flue-cured tobacco leaves. The addition of soil conditioners (straw, dolomite, and lime) increased both the total reads and effective sequences of soil microorganisms. Bacterial diversity was more sensitive to changes in the external environment compared to soil fungi. The application of soil amendments (lime and straw) promoted the growth of beneficial microorganisms in the soil. Additionally, bacterial species had greater competition and limited availability of resources for survival compared to fungi. The results showed that soil microorganisms were significantly influenced by the presence of AK, AN, and pH contents. These findings can provide an effective method for improving the quality of flue-cured tobacco leaves and guiding the amelioration of acidic soil in regions where tobacco-rice rotation is practiced.


Subject(s)
Calcium Compounds , Nicotiana , Oxides , Plant Leaves , Soil Microbiology , Soil , Soil/chemistry , Calcium Compounds/pharmacology , Calcium Compounds/chemistry , Microbiota/drug effects , Agriculture/methods , China
18.
Environ Pollut ; 350: 124011, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38641034

ABSTRACT

The clean and efficient utilization of municipal solid waste (MSW) has attracted increasing concerns in recent years. Pyrolysis of MSW is one of the promising options due to the production of high-value intermediates and the inhibition of pollutants at reducing atmosphere. Herein, the formation behavior of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) during MSW pyrolysis and incineration was experimentally investigated and compared. The influence of reaction temperature, CaO addition, and redox atmosphere on PCDD/Fs formation were compared and discussed. The results showed as the pyrolysis temperature increased, the mass concentration and international toxicity equivalence quantity of PCDD/Fs initially peaked at ∼750 °C before declining. Most of the generated PCDD/Fs were concentrated in the liquid and gaseous products, accounting for ∼90% of the total. Among liquid products, octachlorodibenzo-p-dioxin (O8CDD), 2,3,4,7,8-pentachlorodibenzofuran and 1,2,3,4,6,7,8-heptachlorodibenzofuran (H7CDF) were the most crucial mass concentration contributors, while in gas products, high-chlorinated PCDD/Fs, such as O8CDD, octachlorodibenzofuran (O8CDF) and 1,2,3,4,6,7,8-H7CDF were predominant. Compared to incineration, the formation of PCDD/Fs was 7-20 times greater than that from pyrolysis. This discrepancy can be attributed to the hydrogen-rich and oxygen-deficient atmosphere during pyrolysis, which effectively inhibited the Deacon reaction and the formation of C-Cl bonds, thereby reducing the active chlorine in the system. The addition of in-situ CaO additives also decreased the active chlorine content in the system, bolstering the inhibiting of PCDD/Fs formation during MSW pyrolysis.


Subject(s)
Calcium Compounds , Incineration , Oxidation-Reduction , Oxides , Polychlorinated Dibenzodioxins , Pyrolysis , Polychlorinated Dibenzodioxins/chemistry , Polychlorinated Dibenzodioxins/analysis , Calcium Compounds/chemistry , Oxides/chemistry , Dibenzofurans, Polychlorinated/chemistry , Temperature , Solid Waste , Air Pollutants/analysis , Air Pollutants/chemistry , Benzofurans/chemistry
19.
Waste Manag ; 182: 207-214, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38670004

ABSTRACT

The objective of this paper is to evaluate the feasibility of co-processing wind turbine blade (WTB) material in cement manufacturing to provide an end-of-life means to divert the solid waste of decommissioned WTBs from landfills. Many WTBs consist primarily of glass fiber reinforced thermoset polymers that are difficult to recover or recycle. Portland cement is produced world-wide in large quantities, requiring immense quantities of raw materials (mostly calcium oxide and silicon oxide) and kiln temperatures approaching 1,450 °C. This work contributes analyses of WTB material composition, and predicts the energy provided through the combustible components of the WTBs and raw material contributions provided by incorporating the incombustible components of the WTBs to produce cement. Approximately 40 to 50 % of the WTB material will contribute as fuel to cement production, and approximately 50 to 60 % of the WTB material is expected to be incombustible. One tonne of WTB material can displace approximately 0.4 to 0.5 tonne of coal, while also contributing approximately 0.1 tonne of calcium oxide and 0.3 tonne of silicon oxide as raw material to the cement production process. The glass fiber WTB tested had an average boron content of 4.5 % in the ash. The effects of this high boron content on the cement and its production process should be evaluated. Co-processing WTBs in cement plants will slightly reduce combustion-related CO2 emissions due to avoided calcination. It seems feasible to co-process glass-fiber reinforced WTBs in cement production as WTBs provide suitable raw materials and compatible fuel for this process.


Subject(s)
Construction Materials , Construction Materials/analysis , Recycling/methods , Wind , Calcium Compounds/chemistry , Waste Management/methods , Solid Waste/analysis , Glass , Oxides
20.
Chemosphere ; 357: 142114, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38663679

ABSTRACT

The designed synthesis of an S-scheme heterojunction has possessed a great potential for improving photocatalytic wastewater treatment by demonstrating increased the photoredox capacity and improved the charge separation efficiency. Here, we introduce the fabrication of a heterojunction-based photocatalyst comprising bismuth oxychloride (BiOCl) and bismuth-based halide perovskite (BHP) nanosheets, derived from metal-organic frameworks (MOFs). Our composite photocatalyst is synthesized through a one-pot solvothermal strategy, where a halogenation process is applied to a bismuth-based metal-organic framework (CAU-17) as the precursor for bismuth sourcing. As a result, the rod-like structure of CAU-17 transforms into well-defined plate and nanosheet architectures after 4 and 8 h of solvothermal treatment, respectively. The modulation of the solvothermal reaction time facilitates the establishment of an S-scheme heterojunction, resulting in an increase in the photocatalytic degradation efficiency of rhodamine B (RhB) and sulfamethoxazole (SMX). The optimized BiOCl/BHP composite exhibits superior RhB and SMX degradation rates, achieving 99.8% degradation of RhB in 60 min and 75.1% degradation of SMX in 300 min. Also, the optimized BiOCl/BHP composite (CAU-17-st-8h sample) exhibited the highest rate constant (k = 3.48 × 10-3 min-1), nearly 6 times higher than that of the bare BHP in the photocatalytic degradation process of SMX. The enhanced photocatalytic efficiency can be endorsed to various factors: (i) the in-situ formation of two-components BiOCl/BHP photocatalyst, derived from CAU-17, effectively suppresses the aggregation of pristine BHP and BiOCl particles; (ii) the S-scheme heterostructure establishes a closely-knit interfacial connection, thereby facilitating efficient pathways for charge separation/transfer; and (iii) the BiOCl/BHP heterostructure enhances its capacity to absorb visible light. Our investigation establishes an effective strategy for constructing heterostructured photocatalysts, offering significant potential for application in photocatalytic wastewater treatment.


Subject(s)
Bismuth , Calcium Compounds , Metal-Organic Frameworks , Oxides , Rhodamines , Titanium , Water Pollutants, Chemical , Bismuth/chemistry , Titanium/chemistry , Calcium Compounds/chemistry , Oxides/chemistry , Catalysis , Water Pollutants, Chemical/chemistry , Metal-Organic Frameworks/chemistry , Rhodamines/chemistry , Photolysis , Wastewater/chemistry , Photochemical Processes
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