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1.
Mikrochim Acta ; 191(5): 247, 2024 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-38587580

RESUMO

Alumina inorganic molecularly imprinted polymer (MIP) modified multi-walled carbon nanotubes (MWCNTs) on a glassy carbon electrode (MWCNTs-Al2O3-MIP/GCE) was firstly designed and fabricated by one-step electro deposition technique for the detection of uric acid (UA) in sweat. The UA templates were embedded within the inorganic MIP by co-deposition with Al2O3. Through the evaluation of morphology and structure by Field Emission Scanning Electron Microscope (SEM), Energy Dispersive X-ray Spectroscopy (EDS), X-ray Photoelectron Spectroscopy (XPS) and Transmission Electron Microscopy (TEM), it was verified that the specific recognition sites can be fabricated in the electrodeposited Al2O3 molecular imprinted layer. Due to the high selectivity of molecular imprinting holes, the MWCNTs-Al2O3-MIP/GCE electrode demonstrated an impressive imprinting factor of approximately 2.338 compared to the non-molecularly imprinted glassy carbon electrode (MWCNTs-Al2O3-NIP/GCE) toward uric acid detection. Moreover, it exhibited a remarkable limit of detection (LOD) of 50 nM for UA with wide detection range from 50 nM to 600 µM. The MWCNTs-Al2O3-MIP/GCE electrode also showed strong interference resistance against common substances found in sweat. These results highlight the excellent interference resistance and selectivity of MWCNTs-Al2O3-MIP/GCE sensor, positioning it as a novel sensing platform for non-invasive uric acid detection in human sweat.


Assuntos
Nanotubos de Carbono , Fosfatos , Suor , Humanos , Polímeros Molecularmente Impressos , Ácido Úrico , Óxido de Alumínio
2.
J Mech Behav Biomed Mater ; 154: 106533, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38598918

RESUMO

The present work aims to develop a production method of pre-sintered zirconia-toughened-alumina (ZTA) composite blocks for machining in a computer-aided design and computer-aided manufacturing (CAD-CAM) system. The ZTA composite comprised of 80% Al2O3 and 20% ZrO2 was synthesized, uniaxially and isostatically pressed to generate machinable CAD-CAM blocks. Fourteen green-body blocks were prepared and pre-sintered at 1000 °C. After cooling and holder gluing, a stereolithography (STL) file was designed and uploaded to manufacture disk-shaped specimens projected to comply with ISO 6872:2015. Seventy specimens were produced through machining of the blocks, samples were sintered at 1600 °C and two-sided polished. Half of the samples were subjected to accelerated autoclave hydrothermal aging (20h at 134 °C and 2.2 bar). Immediate and aged samples were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Optical and mechanical properties were assessed by reflectance tests and by biaxial flexural strength test, Vickers indentation and fracture toughness, respectively. Samples produced by machining presented high density and smooth surfaces at SEM evaluation with few microstructural defects. XRD evaluation depicted characteristic peaks of alpha alumina and tetragonal zirconia and autoclave aging had no effect on the crystalline spectra of the composite. Optical and mechanical evaluations demonstrated a high masking ability for the composite and a characteristic strength of 464 MPa and Weibull modulus of 17, with no significant alterations after aging. The milled composite exhibited a hardness of 17.61 GPa and fracture toughness of 5.63 MPa m1/2, which remained unaltered after aging. The synthesis of ZTA blocks for CAD-CAM was successful and allowed for the milling of disk-shaped specimens using the grinding method of the CAD-CAM system. ZTA composite properties were unaffected by hydrothermal autoclave aging and present a promising alternative for the manufacture of infrastructures of fixed dental prostheses.


Assuntos
Óxido de Alumínio , Cerâmica , Teste de Materiais , Óxido de Alumínio/química , Cerâmica/química , Propriedades de Superfície , Zircônio/química , Desenho Assistido por Computador , Materiais Dentários
3.
Proc Inst Mech Eng H ; 238(4): 438-443, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38439747

RESUMO

With low wear rates shown by contemporary bearing materials of total hip prostheses, the standard deviation of wear rate is relatively high. Therefore, large sample sizes are needed for an adequate power of test. Because wear tests take a long time, it is practical to test several samples simultaneously. A new high-capacity, multidirectional wear test device, called the SuperCTPOD-200, was introduced. A 3 million-cycle wear test with an unprecedented sample size of 200 was performed for VEXLPE. The duration of the test was 6 weeks. The wear factor was normally distributed with a mean ± SD of 1.64 × 10-7 mm3/Nm ± 0.22 × 10-7 mm3/Nm (n = 200). The observation that SD was 13.1% of the mean can be useful in power analyses of future tests with other highly cross-linked polyethylenes. Burnishing was the most typical feature on the worn pins, which was in agreement with clinical findings on retrieved acetabular liners. The present study emphasizes statistics that often plays a minor role only in wear studies.


Assuntos
Artroplastia de Quadril , Prótese de Quadril , Humanos , Teste de Materiais , Óxido de Alumínio , Polietilenos , Falha de Prótese
4.
J Orthop Traumatol ; 25(1): 12, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38430413

RESUMO

BACKGROUND: Alumina particles from the grit blasting of Ti-alloy stems are suspected to contribute to aseptic loosening. An alumina-reduced stem surface was hypothesized to improve osseointegration and show comparable short-term outcomes to those of a standard stem. METHODS: In this prospective, double-blind, randomized trial, 26 standard (STD) and 27 experimental new technology (NT) stems were implanted. The latter were additionally treated by acid etching and ice blasting to remove alumina particles from the grit-blasting process. Follow-up occurred at 12 and 24 months. Bone mineral density (BMD) around the stem was measured by a dual-energy x-ray absorptiometry device (DEXA). Radiographs were reviewed for alterations. Clinical scoring comprised the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and the Harris Hip Score (HHS). Survival rates were calculated up to 50 months. RESULTS: Lower mean BMD and more severe cortical hypertrophies were found in the NT group. At 12 months, radiolucent lines were observed mostly in the metaphyseal zone for both groups, with a progression tendency in the NT group at 24 months. At 12 months, pain scores and the WOMAC total and physical activity scores were significantly lower in the NT group, without any differences thereafter. The number of NT stem revisions amounted to 6 (24%) and 11 (41%) at 24 and 50 months, respectively. CONCLUSION: In the NT group, unexpected catastrophic failure rates of 41% caused by early aseptic loosening were noted within 50 months. Compared with the STD stems, NT stems lead to poor clinical and radiographic results. LEVEL OF EVIDENCE: II. TRIAL REGISTRATION: NCT05053048.


Assuntos
Artroplastia de Quadril , Prótese de Quadril , Humanos , Absorciometria de Fóton , Óxido de Alumínio , Artroplastia de Quadril/métodos , Seguimentos , Estudos Prospectivos , Desenho de Prótese , Falha de Prótese , Resultado do Tratamento , Método Duplo-Cego
5.
Luminescence ; 39(3): e4724, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38523053

RESUMO

For white light-rendering research activities, interpretation by using colored emitting materials is an alternative approach. But there are issues in designing the white color emitting materials. Particularly, differences in thermal and decay properties of discrete red, green, and blue emitting materials led to the quest for the search of a single-phased material, able to emit primary colors for white light generation. The current study is an effort to design a simple, single-phase, and cost-effective material with the tunable emission of primary colors by a series of Mg1-xBaxAl2O4:Mn2+ nanopowders. Doping of manganese ion (Mn2+) in the presence of the larger barium cation (Ba2+) at tetrahedral-sites of the spinel magnesium aluminate (MgAl2O4) structure led to the creation of antisite defects. Doped samples were found to have lower bandgaps compared with MgAl2O4, and hybridization of 3d-orbitals of Mn2+ with O(2p), Mg(2s)/Al(2s3p) was found to be responsible for narrowing the bandgap. The distribution of cations at various sites at random results in a variety of electronic transitions between the valance band and oxygen vacancies as well as electron traps produced the antisite defects. The suggested compositions might be used in white light applications since they have three emission bands with centers at 516 nm (green), 464 nm (blue) and 622 nm (red) at an excitation wavelength of 380 nm. A detailed discussion to analyze the effects of the larger cationic radius of Ba2+ on the lattice strain, unit cell parameters, and cell volumes using X-ray diffraction analysis is presented.


Assuntos
Óxido de Alumínio , Óxido de Magnésio , Cristalografia por Raios X , Eletrônica
6.
Chemosphere ; 353: 141586, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38452980

RESUMO

Heterogeneous activation of peroxomonosulfate (PMS) has been extensively studied for the degradation of antibiotics. The cobalt ferrite spinel exhibits good activity in the PMS activation, but suffers from the disadvantage of low PMS utilization efficiency. Herein, the nanocomposites including FeS, CoS2, CoFe2O4 and Fe2O3 were synthesized by hydrothermal method and used for the first time to activate PMS for the removal of sulfamethoxazole (SMX). The nanocomposites showed superior catalytic activity in which the SMX could be completely removed at 40 min, 0.1 g L-1 nanocomposites and 0.4 mM PMS with the first order kinetic constant of 0.2739 min-1. The PMS utilization efficiency was increased by 29.4% compared to CoFe2O4. Both radicals and non-radicals contributed to the SMX degradation in which high-valent metal oxo dominated. The mechanism analysis indicated that sulfur modification, on one hand, enhanced the adsorption of nanocomposites for PMS, and promoted the redox cycles of Fe2+/Fe3+ and Co2+/Co3+ on the other hand. This study provides new way to enhance the catalytic activity and PMS utilization efficiency of spinel cobalt ferrite.


Assuntos
Óxido de Alumínio , Cobalto , Compostos Férricos , Óxido de Magnésio , Nanocompostos , Sulfametoxazol , Peróxidos
7.
Langmuir ; 40(12): 6077-6093, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38466375

RESUMO

NiCo2O4 spinel composites decorated with metal oxides (Ta2O5), reduced graphene oxide (rGO), polyaminoanthraquinone (PAAQ), and layered double hydroxide hydrotalcite (HTs) were synthesized by the hydrothermal route. The synthesized composites were characterized using X-ray powder diffraction (XRD), Brunauer-Emmett-Teller (BET), high-resolution transmission electron microscopy (HR-TEM), and X-ray photoelectron spectroscopy (XPS) analyses for structural parameters such as surface area, morphology, chemical composition, etc. The production of oxygen by the water oxidation technique is the most suitable eco-friendly method, where rGO@Ta2O5/NiCo2O4 (RTNCO) showed an efficient oxygen evolution reaction (OER) performance under 1 M KOH electrolyte. Lower Tafel slope and overpotential values of 76 mV dec-1 and 315 mV, respectively, were calculated for RTNCO. The photocatalytic degradation efficiencies calculated were MB = 97.86%, RhB = 94.75%, and AP = 96% under UV light illumination within 120 min. The degraded dye solution was tested on mung bean (Vigna radiata) plants to determine the toxicity of the dye solution after 15 days, and the results showed good seed germination similar to that in water as the control. The synthesized materials exhibited better antibacterial activity against Bacillus cereus, Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. Interestingly, the toxicological effects of the degraded dyes and drug solutions were effectively studied in the Caenorhabditis elegans model. The overall results revealed that the synthesized composites are promising for electro-/photocatalytic and biological applications.


Assuntos
Óxido de Alumínio , Caenorhabditis elegans , Grafite , Óxido de Magnésio , Nanocompostos , Animais , Água , Nanocompostos/química , Oxigênio
8.
Sci Rep ; 14(1): 5147, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429352

RESUMO

Rice husk, an agricultural waste from the rice industry, can cause serious environmental pollution if not properly managed. However, rice husk ash (RHA) has been found to have many positive properties, making it a potential replacement for non-renewable peat in soilless planting. Thus, this study investigated the impact of a RHA composite substrate on the growth, photosynthetic parameters, and fruit quality of cucumber (Yuyi longxiang variety) and melon (Yutian yangjiaomi variety). The RHA, peat, vermiculite, and perlite were blended in varying proportions, with the conventional seedling substrate (peat:vermiculite:perlite = 1:1:1 volume ratio) serving as the control (CK). All plants were cultivated in barrels filled with 10L of the mixed substrates. The results from this study found that RHA 40 (RHA:peat:vermiculite:perlite = 4:4:1:1 volume ratio) significantly enhanced substrate ventilation and positively influenced the stem diameter, root activity, seedling index, chlorophyll content, net photosynthetic rate (Pn), stomatal conductance (Gs), and transpiration rate (Tr) of cucumber and melon plants. Additionally, plant planted using RHA 40, the individual fruit weight of cucumber and melon found to increase by 34.62% and 21.67%, respectively, as compared to the control. Aside from that, both cucumber and melon fruits had significantly higher sucrose, total soluble sugar, vitamin C, and soluble protein levels. This subsequently improved the activity of sucrose synthase and sucrose phosphate synthase in both cucumber and melon. In conclusion, the RHA 40 found to best promote cucumber and melon plant growth, increase plant leaf photosynthesis, and improve cucumber and melon fruit quality, making it a suitable substrate formula for cucumber and melon cultivation in place of peat.


Assuntos
Óxido de Alumínio , Silicatos de Alumínio , Cucumis sativus , Cucurbitaceae , Oryza , Dióxido de Silício , Carboidratos da Dieta , Solo
9.
Int J Biol Macromol ; 264(Pt 2): 130766, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38462101

RESUMO

An inorganic/organic nanocomposite was used to develop an afterglow and color-tunable smart window. A combination of polylactic acid (PLA) plastic waste as an environmentally-friendly hosting agent, and lanthanide-activated strontium aluminum oxide nanoparticles (SAON) encapsulated with silica nanoparticles (SAON@Silica) as a photoluminescent efficient agent resulted in a smart organic/inorganic nanocomposite. In order to prepare SAON-encapsulated silica nanoparticles (SAON@Silica), the SAON nanoparticles were coated with silica using the heterogeneous precipitation method. By using transmission electron microscopy (TEM), SAON showed a diameter range of 5-12 nm, while the SAON@Silica nanoparticles showed a diameter range of 50-100 nm. In order to ensure the development of a colorless plastic film, a homogeneous dispersion of the phosphorescent Phosphor@Silica nanoparticles throughout the plastic bulk was confirmed. CIE Lab coordinates and luminescence spectra were used to study the color shift characteristics. Under visible light conditions, the plastic films were transparent. The photoluminescent films emitted green light at 525 nm when excited at 375 nm. The hydrophobicity and ultraviolet protection were enhanced without altering the fundamental physico-mechanical performance of the plastic sheet. The current color-tunable plastic can be used in many potential applications, such as warning signs, anti-counterfeiting barcodes, smart windows, and protective apparel.


Assuntos
Metais Terras Raras , Nanopartículas , Dióxido de Silício , Poliésteres , Óxido de Alumínio , Alumínio
10.
J Environ Manage ; 356: 120751, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38531131

RESUMO

Cost-effective treatment or even valorization of the bauxite residue (red mud) from the alumina industry is in demand to improve their environmental and economic liabilities. This study proposes a strategy that provides a near-complete conversion of bauxite residue to valuable products. The first step involves dilute acid leaching, which allowed the fractionation of raw residues into (1) an aqueous fraction rich in silica and aluminium and (2) a solid residue rich in iron, titanium and rare earth elements. For the proposed process, 91% of the original silicon, 67% of the aluminium, 78% of the scandium and 69% of the cerium were recovered. The initial cost evaluation suggested that this approach is profitable with a gross margin of 167 $US per tonne. This "Residue2Product" approach should be considered for large-scale practices as one of the most economical and sustainable solutions to this environmental and economic liability for the alumina industry.


Assuntos
Óxido de Alumínio , Alumínio , Óxido de Alumínio/química , Ferro , Titânio , Água
11.
Lasers Surg Med ; 56(3): 257-262, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38414118

RESUMO

OBJECTIVES: Café-au-lait macules (CALM) are benign birthmarks presenting as uniformly pigmented, well demarcated, brown patches that can be distressing to patients, especially when located in cosmetically sensitive areas. As with all pigmentary lesions in skin of color patients, CALMs have been particularly challenging to treat. Here we present the first case series characterizing treatment parameters and clinical outcomes utilizing the 730-nm picosecond titanium sapphire laser for the treatment of CALMs. This device provides an additional safe and effective treatment option for these challenging cases. METHODS: We performed a retrospective review of patients treated at a single institution between April 2021 and December 2023. Clinical photographs were graded by 3 outside board-certified dermatologists using a 5-point visual analog scale. RESULTS: Fourteen patients (age range: 10 months-66 years, mean age: 27.4 years, Fitzpatrick skin types II-VI) were treated for CALM on the face (11) or body (3). On average, patients received 4.3 treatments, with treatment intervals ranging from 4 to 40 weeks. Treatment remains ongoing with the 730-nm picosecond laser for eight patients. Overall, patients were rated to have a mean improvement of 26%-50%. Two patients (FST III and VI) achieved 100% clearance after 4-5 treatment sessions. Our study included four patients whose CALM were of the smooth bordered "coast of California" subtype, three of whom had a mean improvement rating of only 1%-25%. The fourth patient had near complete resolution. Follow up for these patients has ranged from 6 weeks to 1.5 years. Of the patients treated, one patient experienced transient post-inflammatory hyperpigmentation and another transient post-inflammatory hypopigmentation, while a third patient experienced mild persistent guttate hypopigmentation. Three patients experienced partial recurrence indicating that maintenance treatments may be needed in some patients. CONCLUSION: The 730-nm picosecond titanium sapphire laser is a safe and efficacious treatment option, in the right morphologic setting, to improve the cosmetic appearance of CALMs in a wide range of ages and skin types. To our knowledge, this is the first reported treatment of CALMs with picosecond lasers in FST V and VI patients. Our study also supports prior studies which have found that CALM with smooth-bordered "coast of California" morphology have a poor response to laser therapy as compared to those with jagged or ill-defined bordered "coast of Maine" morphology.


Assuntos
Hiperpigmentação , Hipopigmentação , Lasers de Estado Sólido , Humanos , Lactente , Adulto , Titânio , Lasers de Estado Sólido/uso terapêutico , Manchas Café com Leite/radioterapia , Resultado do Tratamento , Hiperpigmentação/etiologia , Hipopigmentação/etiologia , Óxido de Alumínio
12.
Talanta ; 271: 125714, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38306812

RESUMO

Spinel oxide has great promise in constructing highly active nanozymes due to its tunable crystal structure. However, it still faces the problems of poor specificity and insufficient enzyme activity, which limits its application in the field of analysis. Herein, a series of transition metal spinel oxides were synthesized by cation regulation strategy, and their enzymatic activity and catalytic mechanism were analyzed. Interestingly, FeCo2O4, Co3O4 and NiCo2O4 had oxidase-like activity and peroxidase-like activity, while CuCo2O4 had specific and high oxidase-like activity. Their oxidase-like activities follow the order of FeCo2O4 < Co3O4 < NiCo2O4 < CuCo2O4, which is consistent with their cation radius. The smaller the cation radius of tetrahedral site, the more beneficial it is to increase the oxidase-like activity. The high oxidase-like activity of CuCo2O4 may be attributed to the production of 1O2, •O2- and •OH. EPR results showed the presence of abundant oxygen vacancies in CuCo2O4. Upon the introduction of EDTA, TMB color reaction fades because of oxygen vacancies elimination by EDTA, indicating that oxygen vacancies played an important role in the reaction. Based on the inhibition effect of caffeic acid on the high oxidase-like activity of CuCo2O4, a simple and sensitive caffeic acid colorimetric sensing platform was developed. The linear range for the detection of caffeic acid is 0.02-15 µM, with a detection limit as low as 13 nM. The constructed sensor enables the detection of caffeic acid in caffeic acid tablets and actual water samples, providing a new strategy for the detection of caffeic acid and drug quality control.


Assuntos
Óxido de Alumínio , Ácidos Cafeicos , Cobalto , Colorimetria , Óxido de Magnésio , Óxidos , Oxigênio , Ácido Edético , Cátions , Oxirredutases
13.
Int J Mol Sci ; 25(4)2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38396933

RESUMO

Bioinert materials such as the zirconium dioxide and aluminum oxide are widely used in surgery and dentistry due to the absence of cytotoxicity of the materials in relation to the surrounding cells of the body. However, little attention has been paid to the study of metabolic processes occurring at the implant-cell interface. The metabolic activity of mouse 3T3 fibroblasts incubated on yttrium-stabilized zirconium ceramics cured with aluminum oxide (ATZ) and stabilized zirconium ceramics (Y-TZP) was analyzed based on the ratio of the free/bound forms of cofactors NAD(P)H and FAD obtained using two-photon microscopy. The results show that fibroblasts incubated on ceramics demonstrate a shift towards the free form of NAD(P)H, which is observed during the glycolysis process, which, according to our assumptions, is related to the porosity of the surface of ceramic structures. Consequently, despite the high viability and good proliferation of fibroblasts assessed using an MTT test and a scanning electron microscope, the cells are in a state of hypoxia during incubation on ceramic structures. The FLIM results obtained in this work can be used as additional information for scientists who are interested in manufacturing osteoimplants.


Assuntos
Interface Osso-Implante , NAD , Zircônio , Animais , Camundongos , Óxido de Alumínio , Cerâmica/química , Fibroblastos/metabolismo , Teste de Materiais , NAD/metabolismo , Propriedades de Superfície , Ítrio , Zircônio/química
14.
J Chromatogr A ; 1719: 464712, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38377662

RESUMO

A drastic increase in demand for electric vehicles and energy storage systems increases lithium (Li) need as a critical metal for the 21st century. Lithium manganese oxides stand out among inorganic adsorbents because of their high capacity, chemical stability, selectivity, and affordability for lithium recovery from aqueous media. This study investigates using hydrometallurgically synthesized lithium manganese oxide (Li1.6Mn1.6O4) in granular form coated with cross-linked chitosan for lithium recovery from water. Characterization methods such as SEM, FTIR, XRD, and BET reveal the successful synthesis of the composite adsorbent. Granular cross-linked chitosan-coated and delithiated lithium manganese oxide (CTS/HMO) adsorbent demonstrated optimal removal efficiency of 86 % at pH 12 with 4 g/L of adsorbent dosage. The Langmuir isotherm at 25 °C, which showed monolayer adsorption with a maximum capacity of 4.94 mg/g, a better fit for the adsorption behavior of CTS/HMO. Adsorption was endothermic and thermodynamically spontaneous. Lithium adsorption followed the pseudo-first-order kinetic model.


Assuntos
Óxido de Alumínio , Quitosana , Óxido de Magnésio , Poluentes Químicos da Água , Água , Manganês , Lítio , Quitosana/química , Adsorção , Óxidos/química , Cinética , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio
15.
Dent Mater J ; 43(2): 216-226, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38417860

RESUMO

This study aimed to investigate the effects of sandblasting on the physical properties and bond strength of two types of translucent zirconia: niobium-oxide-containing yttria-stabilized tetragonal zirconia polycrystals ((Y, Nb)-TZP) and 5 mol% yttria-partially stabilized zirconia (5Y-PSZ). Fully sintered disc specimens were either sandblasted with 125 µm alumina particles or left as-sintered. Surface roughness, crystal phase compositions, and surface morphology were explored. Biaxial flexural strength (n=10) and shear bond strength (SBS) (n=12) were evaluated, including thermocycling conditions. Results indicated a decrease in flexural strength of 5Y-PSZ from 601 to 303 MPa upon sandblasting, while (Y, Nb)-TZP improved from 458 to 544 MPa. Both materials significantly increased SBS after sandblasting (p<0.001). After thermocycling, (Y, Nb)-TZP maintained superior SBS (14.3 MPa) compared to 5Y-PSZ (11.3 MPa) (p<0.001). The study concludes that (Y, Nb)-TZP is preferable for sandblasting applications, particularly for achieving durable bonding without compromising flexural strength.


Assuntos
Materiais Dentários , Nióbio , Óxidos , Materiais Dentários/química , Teste de Materiais , Propriedades de Superfície , Zircônio/química , Ítrio/química , Óxido de Alumínio , Resistência ao Cisalhamento
16.
BMC Plant Biol ; 24(1): 149, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38418950

RESUMO

BACKGROUND: Consecutive droughts and quantitative and qualitative reduction of surface and underground water resources have caused an increase in greenhouse and hydroponic cultivation for most garden crops, including strawberries, in Iran. On the other hand, most of the inputs of greenhouse crops in Iran are imported. To possibility of replacing vermicompost with peat moss under hydroponic cultivation, an experiment was done in a split plot based on randomized complete blocks design in three replications in Isfahan (Iran) Agricultural and Natural Resources Research Center in 2019. The main treatment was substrate at four levels included different levels of vermicompost (30 and 50%) and peat moss (30 and 50%) in combination with perlite and sub-treatment were Selva and Camarosa cultivars. RESULTS: The results showed that Camarosa cultivar and Selva cultivar in (perlite/ peat moss 50:50) and Selva cultivar in (perlite / vermicompost 70:30) had maximum yield. Leaf number and chlorophyll index were maximum in Camarosa cultivar in peat moss substrates. Strawberry cultivars had the highest root fresh weight, the content of vitamin C and total soluble solids (TSS) in substrates containing vermicompost. Camarosa cultivar in (perlite / peat moss50:50) and Selva cultivar in (perlite /vermicompost 50:50) had maximum root dry weight. Also, the highest number of inflorescences was related to substrates containing peat moss and (perlite /vermicompost 70:30). Maximum amount of fresh and dry weight of shoots were observed in (perlite/ peat moss70:30). Selva cultivar had more inflorescences (16.5%) than Camarosa cultivar and Camarosa cultivar produced more fresh and dry weight of shoots (16.5%, 23.01%) than Selva cultivar. CONCLUSION: Expriment results highlighted the importance of considering both main and sub-treatments in agricultural research, as they interacted to influence various growth and yield parameters. 50% vermicompost treatment combined with perlite had a positive impact on plant growth and in quality index such as vitamin C content and TSS was highest. while the choice of cultivar affected different aspects of plant development. Selva cultivar was known to be more tolerant to salinity caused by vermicompost. Vermicompost is local and more economical, also salt resistant cultivars are recommended in a controlled (30%) amount of vermicompost.


Assuntos
Óxido de Alumínio , Fragaria , Dióxido de Silício , Sphagnopsida , Solo , Ácido Ascórbico
17.
Chemosphere ; 352: 141366, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38311037

RESUMO

The oxidation of pyrite results in the formation of a solid film passivation layer on its surface. This layer effectively hinders the direct interaction between H2O, O2, and the pyrite surface, thereby impeding the oxidation dissolution of pyrite. There are few studies on whether alumina (Al2O3), a common aluminum-containing oxide, affects the formation of a solid film passivation layer on the surface of pyrite and inhibits the oxidation dissolution of pyrite. This research investigates the impact of Al2O3 incorporation on the speciation transformation of S, Fe, and Al on the surface of pyrite during oxygen pyrite process. The oxidation of pyrite followed the "polysulfide-thiosulfate" complex oxidation pathway. When <1.5 g/L Al2O3 was introduced, it increase pyrite oxidation, whereas ≥1.5 g/L Al2O3 prevented pyrite oxidation. The process of Al2O3 dissolution results in the consumption of H+ and the subsequent release of Al3+. This, in turn, facilitates the hydrolysis of Fe3+ and Al3+ to generate a secondary mineral layer on the pyrite surface. As a result of the accumulation of S promotes the formation of polysulfide chemical (FeSn) or iron deficiency sulfide (Fe1-xS), resulting in the formation of a solid film passivation layer composed of sulfur film and secondary mineral layer. The results demonstrated that Al2O3 can promote the formation of a solid film passivation layer on the surface of pyrite, which has significant implications for controlling the oxidation dissolution process of pyrite and offers a new perspective for the source control of acid mine drainage.


Assuntos
Óxido de Alumínio , Ferro , Minerais , Sulfetos/metabolismo , Oxirredução , Estresse Oxidativo
18.
Int J Food Microbiol ; 414: 110612, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38325258

RESUMO

Microgreens can be contaminated by various preharvest sources including soilless substrate, plant nutrition solution, water and seeds. The aim of this study was to determine the transfer level of Salmonella, Shiga toxin-producing Escherichia coli O157:H7, and Listeria monocytogenes to the edible part of various type of microgreens from plant nutrient solution-soaked perlite as soilless substrate or seeds. Ampicillin resistant 3-strain cocktails of Salmonella and E. coli O157:H7 and non-resistant L. monocytogenes were independently inoculated into plant nutrient solution-soaked perlite and seeds in low (102-103 CFU/g) and high (105-106 CFU/g) populations. Twenty types of microgreens were grown in inoculated perlite. The seed inoculation was performed on five types of microgreens. Correlations between pathogen transfer levels with seed characteristics and harvest time were assessed. Pathogen populations (1.6 ± 0.2 to 7.7 ± 0.1 log CFU/g) transferred to microgreens were dependent on type of pathogen and microgreen but not affected by contamination source and inoculation level. The level of pathogen transferred to microgreens had a moderate to high negative correlations (R2) with seed surface area (-0.551 to -0.781), seed weight (-0.735 to -0.818), and harvest time (-0.332 to -0.919) when grown in Salmonella and E. coli O157:H7 inoculated perlite. This study suggests a high risk of pathogen population transferring to microgreens in case of seed or soilless substrate contamination when pathogen growth or survival is supported in plant nutrient solution.


Assuntos
Óxido de Alumínio , Escherichia coli O157 , Listeria monocytogenes , Dióxido de Silício , Microbiologia de Alimentos , Contagem de Colônia Microbiana , Salmonella , Sementes
19.
Chemosphere ; 352: 141428, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38340999

RESUMO

Ferromanganese spinel oxides (MnFe2O4, MFO) have been proven effective in activating persulfate for pollutants removal. However, their inherent high surface energy often leads to agglomeration, diminishing active sites and consequently restricting catalytic performance. In this study, using Al-MCM-41 (MCM) mesoporous molecular sieves derived from natural attapulgite as a support, the MFO/MCM composite was synthesized through dispersing MnFe2O4 nanoparticles on MCM carrier by a simple hydrothermal method, which can effectively activate persulfate (PS) to degrade Tetracycline (TC). The addition of Al-MCM-41 can effectively improve the specific surface area and adsorption performance of MnFe2O4, but also reduce the leaching amount of metal ions. The MFO/MCM composite exhibited superior catalytic reactivity towards PS and 84.3% removal efficiency and 64.7% mineralization efficiency of TC (20 mg/L) was achieved in 90 min under optimized conditions of 0.05 mg/L catalyst dosage, 5 mM PS concentration, room temperature and no adjustment of initial pH. The effects of various stoichiometric MFO/MCM ratio, catalyst dosage, PS concentration, initial pH value and co-existing ions on the catalytic performance were investigated in detail. Moreover, the possible reaction mechanism in MFO-MCM/PS system was proposed based on the results of quenching tests, electron paramagnetic resonance (EPR) and XPS analyses. Finally, major degradation intermediates of TC were detected by liquid chromatography mass spectrometry technologies (LC-MS) and four possible degradation pathways were proposed. This study enhances the design approach for developing highly efficient, environmentally friendly and low-cost catalysts for the advanced treatment process of antibiotic wastewater.


Assuntos
Óxido de Alumínio , Ferro , Compostos de Magnésio , Óxido de Magnésio , Manganês , Óxidos , Compostos de Silício , Dióxido de Silício , Poluentes Químicos da Água , Antibacterianos , Tetraciclina/química , Poluentes Químicos da Água/análise
20.
Int J Oral Maxillofac Implants ; 39(1): 173-183, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38416011

RESUMO

PURPOSE: To determine the characteristics of dental implant transmucosal surfaces that influence soft tissue attachment and marginal bone loss (MBL). MATERIALS AND METHODS: The PubMed, Embase, and Cochrane Library electronic databases were searched based on predefined PICO eligibility criteria. Data from animal studies that compared junctional epithelium and connective tissue attachment and MBL from 4 days to 72 weeks were analyzed. The risk of bias was performed with the Systematic Review Centre for Laboratory Animal Experimentation tool. A rank analysis evaluation of data was performed, and the most frequently appearing materials/surfaces for each tissue compartment were identified. RESULTS: The search identified 3,549 studies, 28 of which were eligible for analysis, with an average risk of bias of 28% ± 10%. Machined, polished, etched, sandblasted, or coated titanium and zirconia materials/surfaces were most frequently examined. Several studies investigated lithium disilicate, polyether ether ketone (PEEK) or polyether ketone ketone (PEKK), aluminum oxide, and gold. Based on ranking and frequency of use at different time points, titanium grade IV (Ti-4) microthreads with a polished neck area most frequently supported natural tooth-like junctional epithelial attachment (≤ 1.5 mm), while machined Ti-4 and machined titanium grade V (Ti-5) most frequently supported connective tissue attachment (≤ 1.25 mm) and led to the least MBL (≤ 0.75 mm). CONCLUSIONS: Analyzed data suggest that Ti-4 microthreads with a polished neck area and machined Ti-4 and Ti-5 were the materials/surfaces of choice for the transmucosal part of implants. However, the extensive heterogeneity in reported studies precludes solid identification of the best materials/surfaces.


Assuntos
Doenças Ósseas Metabólicas , Implantes Dentários , Animais , Implantes Dentários/efeitos adversos , Titânio , Óxido de Alumínio , Inserção Epitelial
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