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1.
J Environ Sci (China) ; 147: 561-570, 2025 Jan.
Article in English | MEDLINE | ID: mdl-39003071

ABSTRACT

In the present study, we investigated the influence of surface fluorine (F) on TiO2 for the photocatalytic oxidation (PCO) of toluene. TiO2 modified with different F content was prepared and tested. It was found that with the increasing of F content, the toluene conversion rate first increased and then decreased. However, CO2 mineralization efficiency showed the opposite trend. Based on the characterizations, we revealed that F substitutes the surface hydroxyl of TiO2 to form the structure of Ti-F. The presence of the appropriate amount of surface Ti-F on TiO2 greatly enhanced the separation of photogenerated carriers, which facilitated the generation of ·OH and promoted the activity for the PCO of toluene. It was further revealed that the increase of only ·OH promoted the conversion of toluene to ring-containing intermediates, causing the accumulation of intermediates and then conversely inhibited the ·OH generation, which led to the decrease of the CO2 mineralization efficiency. The above results could provide guidance for the rational design of photocatalysts for toluene oxidation.


Subject(s)
Fluorides , Oxidation-Reduction , Titanium , Toluene , Toluene/chemistry , Titanium/chemistry , Catalysis , Fluorides/chemistry , Photochemical Processes , Models, Chemical
2.
Biomaterials ; 313: 122772, 2025 Feb.
Article in English | MEDLINE | ID: mdl-39190942

ABSTRACT

Implant-associated infection (IAI) has become an intractable challenge in clinic. The healing of IAI is a complex physiological process involving a series of spatiotemporal connected events. However, existing titanium-based implants in clinic suffer from poor antibacterial effect and single function. Herein, a versatile surface platform based on the presentation of sequential function is developed. Fabrication of titania nanotubes and poly-γ-glutamic acid (γ-PGA) achieves the efficient incorporation of silver ions (Ag+) and the pH-sensitive release in response to acidic bone infection microenvironment. The optimized PGA/Ag platform exhibits satisfactory biocompatibility and converts macrophages from pro-inflammatory M1 to pro-healing M2 phenotype during the subsequent healing stage, which creates a beneficial osteoimmune microenvironment and promotes angio/osteogenesis. Furthermore, the PGA/Ag platform mediates osteoblast/osteoclast coupling through inhibiting CCL3/CCR1 signaling. These biological effects synergistically improve osseointegration under bacterial infection in vivo, matching the healing process of IAI. Overall, the novel integrated PGA/Ag surface platform proposed in this study fulfills function cascades under pathological state and shows great potential in IAI therapy.


Subject(s)
Anti-Bacterial Agents , Polyglutamic Acid , Silver , Titanium , Animals , Titanium/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Mice , Polyglutamic Acid/chemistry , Polyglutamic Acid/analogs & derivatives , Silver/chemistry , Silver/pharmacology , Surface Properties , Nanotubes/chemistry , RAW 264.7 Cells , Prosthesis-Related Infections/drug therapy , Osseointegration/drug effects , Osteogenesis/drug effects , Osteoblasts/drug effects , Osteoblasts/cytology , Macrophages/drug effects , Macrophages/metabolism , Male , Wound Healing/drug effects , Prostheses and Implants
3.
J Environ Sci (China) ; 150: 332-339, 2025 Apr.
Article in English | MEDLINE | ID: mdl-39306408

ABSTRACT

NH3-SCR (SCR: Selective catalytic reduction) is an effective technology for the de-NOx process from both mobile and stationary pollution sources, and the most commonly used catalysts are the vanadia-based catalysts. An innovative V2O5-CeO2/TaTiOx catalyst for NOx removal was prepared in this study. The influences of Ce and Ta in the V2O5-CeO2/TaTiOx catalyst on the SCR performance and physicochemical properties were investigated. The V2O5-CeO2/TaTiOx catalyst not only exhibited excellent SCR activity in a wide temperature window, but also presented strong resistance to H2O and SO2 at 275 ℃. A series of characterization methods was used to study the catalysts, including H2-temperature programmed reduction, X-ray photoelectron spectroscopy, NH3-temperature programmed desorption, etc. It was discovered that a synergistic effect existed between Ce and Ta species. The introduction of Ce and Ta enlarged the specific surface area, increased the amount of acid sites and the ratio of Ce3+, (V3++V4+) and Oα, and strengthened the redox capability which were related to synergistic effect between Ce and Ta species, significantly improving the NH3-SCR activity.


Subject(s)
Ammonia , Cerium , Titanium , Vanadium Compounds , Catalysis , Cerium/chemistry , Titanium/chemistry , Ammonia/chemistry , Vanadium Compounds/chemistry , Air Pollutants/chemistry , Oxidation-Reduction , Air Pollution/prevention & control
4.
J Environ Sci (China) ; 149: 164-176, 2025 Mar.
Article in English | MEDLINE | ID: mdl-39181631

ABSTRACT

Cerium and cobalt loaded Co-Ce/TiO2 catalyst prepared by impregnation method was investigated for photothermal catalytic toluene oxidation. Based on catalyst characterizations (XPS, EPR and H2-TPR), redox cycle between Co and TiO2 (Co2+ + Ti4+ ↔ Co3+ + Ti3+) results in the formation of Co3+, Ti3+ and oxygen vacancies, which play important roles in toluene catalytic oxidation reaction. The introduction of Ce brings in the dual redox cycles (Co2+ + Ti4+ ↔ Co3+ + Ti3+, Co2+ + Ce4+ ↔ Co3+ + Ce3+), further promoting the elevation of reaction sites amount. Under full spectrum irradiation with light intensity of 580 mW/cm2, Co-Ce/TiO2 catalyst achieved 96% of toluene conversion and 73% of CO2 yield, obviously higher than Co/P25 and Co/TiO2. Co-Ce/TiO2 efficiently maintains 10-hour stability test under water vapor conditions and exhibits better photothermal catalytic performance than counterparts under different wavelengths illumination. Photothermal catalytic reaction displays improved activities compared with thermal catalysis, which is attributed to the promotional effect of light including photocatalysis and light activation of reactive oxygen species.


Subject(s)
Cerium , Cobalt , Oxidation-Reduction , Titanium , Toluene , Titanium/chemistry , Cobalt/chemistry , Catalysis , Toluene/chemistry , Cerium/chemistry , Models, Chemical , Photochemical Processes
5.
J Environ Sci (China) ; 149: 234-241, 2025 Mar.
Article in English | MEDLINE | ID: mdl-39181638

ABSTRACT

Reducing the cost of RuO2/TiO2 catalysts is still one of the urgent challenges in catalytic HCl oxidation. In the present work, a Ce-doped TiO2 supported RuO2 catalyst with a low Ru loading was developed, showing a high activity in the catalytic oxidation of HCl to Cl2. The results on some extensive characterizations of both Ce-doped TiO2 carriers and their supported RuO2 catalysts show that the doping of Ce into TiO2 can effectively change the lattice parameters of TiO2 to improve the dispersion of the active RuO2 species on the carrier, which facilitates the production of surface Ru species to expose more active sites for boosting the catalytic performance even under some harsh reaction conditions. This work provides some scientific basis and technical support for chlorine recycling.


Subject(s)
Cerium , Hydrochloric Acid , Oxidation-Reduction , Titanium , Titanium/chemistry , Catalysis , Cerium/chemistry , Hydrochloric Acid/chemistry , Ruthenium Compounds/chemistry , Chlorides/chemistry , Models, Chemical , Chlorine/chemistry
6.
J Environ Sci (China) ; 148: 476-488, 2025 Feb.
Article in English | MEDLINE | ID: mdl-39095182

ABSTRACT

In this study, non-thermal plasma (NTP) was employed to modify the Cu/TiO2 adsorbent to efficiently purify H2S in low-temperature and micro-oxygen environments. The effects of Cu loading amounts and atmospheres of NTP treatment on the adsorption-oxidation performance of the adsorbents were investigated. The NTP modification successfully boosted the H2S removal capacity to varying degrees, and the optimized adsorbent treated by air plasma (Cu/TiO2-Air) attained the best H2S breakthrough capacity of 113.29 mg H2S/gadsorbent, which was almost 5 times higher than that of the adsorbent without NTP modification. Further studies demonstrated that the superior performance of Cu/TiO2-Air was attributed to increased mesoporous volume, more exposure of active sites (CuO) and functional groups (amino groups and hydroxyl groups), enhanced Ti-O-Cu interaction, and the favorable ratio of active oxygen species. Additionally, the X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) results indicated the main reason for the deactivation was the consumption of the active components (CuO) and the agglomeration of reaction products (CuS and SO42-) occupying the active sites on the surface and the inner pores of the adsorbents.


Subject(s)
Copper , Hydrogen Sulfide , Oxidation-Reduction , Titanium , Titanium/chemistry , Adsorption , Copper/chemistry , Hydrogen Sulfide/chemistry , Air Pollutants/chemistry , Plasma Gases/chemistry , Models, Chemical
7.
J Environ Sci (China) ; 148: 515-528, 2025 Feb.
Article in English | MEDLINE | ID: mdl-39095185

ABSTRACT

The reduction of nitrobenzene to aniline is very important for both pollution control and chemical synthesis. Nevertheless, difficulties still remain in developing a catalytic system having high efficiency and selectivity for the production of aniline. Herein, it was found that PdO nanoparticles highly dispersed on TiO2 support (PdO/TiO2) functioned as a highly efficient catalyst for the reduction of nitrobenzene in the presence of NaBH4. Under favorable conditions, 95% of the added nitrobenzene (1 mmol/L) was reduced within 1 min with an ultra-low apparent activation energy of 10.8 kJ/mol by using 0.5%PdO/TiO2 as catalysts and 2 mmol/L of NaBH4 as reductants, and the selectivity to aniline even reached up to 98%. The active hydrogen species were perceived as dominant species during the hydrogenation of nitrobenzene by the results of isotope labeling experiments and ESR spectroscopic. A mechanism was proposed as follows: PdO activates the nitro groups and leads to in-situ generation of Pd, and the generated Pd acts as the reduction sites to produce active hydrogen species. In this catalytic system, nitrobenzene prefers to be adsorbed on the PdO nanoparticles of the PdO/TiO2 composite. Subsequently, the addition of NaBH4 results in in-situ generation of a Pd/PdO/TiO2 composite from the PdO/TiO2 composite, and the Pd nanoclusters would activate NaBH4 to generate active hydrogen species to attack the adsorbed nitro groups. This work will open up a new approach for the catalytic transfer hydrogenation of nitrobenzene to aniline in green chemistry.


Subject(s)
Aniline Compounds , Nitrobenzenes , Palladium , Titanium , Nitrobenzenes/chemistry , Aniline Compounds/chemistry , Titanium/chemistry , Hydrogenation , Catalysis , Palladium/chemistry , Models, Chemical
8.
J Environ Sci (China) ; 148: 57-68, 2025 Feb.
Article in English | MEDLINE | ID: mdl-39095190

ABSTRACT

The expandable graphite (EG) modified TiO2 nanocomposites were prepared by the high shear method using the TiO2 nanoparticles (NPs) and EG as precursors, in which the amount of EG doped in TiO2 was 10 wt.%. Followed by the impregnation method, adjusting the pH of the solution to 10, and using the electrostatic adsorption to achieve spatial confinement, the Pt elements were mainly distributed on the exposed TiO2, thus generating the Pt/10EG-TiO2-10 catalyst. The best CO oxidation activity with the excellent resistance to H2O and SO2 was obtained over the Pt/10EG-TiO2-10 catalyst: CO conversion after 36 hr of the reaction was ca. 85% under the harsh condition of 10 vol.% H2O and 100 ppm SO2 at a high gaseous hourly space velocity (GHSV) of 400,000 hr-1. Physicochemical properties of the catalysts were characterized by various techniques. The results showed that the electrostatic adsorption, which riveted the Pt elements mainly on the exposed TiO2 of the support surface, reduced the dispersion of Pt NPs on EG and achieved the effective dispersion of Pt NPs, hence significantly improving CO oxidation activity over the Pt/10EG-TiO2-10 catalyst. The 10 wt.% EG doped in TiO2 caused the TiO2 support to form a more hydrophobic surface, which reduced the adsorption of H2O and SO2 on the catalyst, greatly inhibited deposition of the TiOSO4 and formation of the PtSO4 species as well as suppressed the oxidation of SO2, thus resulting in an improvement in the resistance to H2O and SO2 of the Pt/10EG-TiO2-10 catalyst.


Subject(s)
Graphite , Oxidation-Reduction , Platinum , Sulfur Dioxide , Titanium , Titanium/chemistry , Graphite/chemistry , Sulfur Dioxide/chemistry , Platinum/chemistry , Catalysis , Carbon Monoxide/chemistry , Water/chemistry , Air Pollutants/chemistry , Models, Chemical
9.
Biomaterials ; 313: 122800, 2025 Feb.
Article in English | MEDLINE | ID: mdl-39241551

ABSTRACT

The (002) crystallographic plane-oriented hydroxyapatite (HA) and anatase TiO2 enable favorable hydrophilicity, osteogenesis, and biocorrosion resistance. Thus, the crystallographic plane control in HA coating and crystalline phase control in TiO2 is vital to affect the surface and interface bioactivity and biocorrosion resistance of titanium (Ti) implants. However, a corresponding facile and efficient fabrication method is absent to realize the HA(002) mineralization and anatase TiO2 formation on Ti. Herein, we utilized the predominant Ti(0002) plane of the fibrous-grained titanium (FG Ti) to naturally form anatase TiO2 and further achieve a (002) basal plane oriented nanoHA (nHA) film through an in situ mild hydrothermal growth strategy. The formed FG Ti-nHA(002) remarkably improved hydrophilicity, mineralization, and biocorrosion resistance. Moreover, the nHA(002) film reserved the microgroove-like topological structure on FG Ti. It could enhance osteogenic differentiation through promoted contact guidance, showing one order of magnitude higher expression of osteogenic-related genes. On the other hand, the nHA(002) film restrained the osteoclast activity by blocking actin ring formation. Based on these capacities, FG Ti-nHA(002) improved new bone growth and binding strength in rabbit femur implantation, achieving satisfactory osseointegration within 2 weeks.


Subject(s)
Durapatite , Osseointegration , Titanium , Titanium/chemistry , Durapatite/chemistry , Animals , Osseointegration/drug effects , Rabbits , Osteogenesis/drug effects , Corrosion , Mice , Coated Materials, Biocompatible/chemistry , Coated Materials, Biocompatible/pharmacology , Cell Differentiation/drug effects
10.
Food Chem ; 462: 140939, 2025 Jan 01.
Article in English | MEDLINE | ID: mdl-39208731

ABSTRACT

Phoxim, extensively utilized in agriculture as an organothiophosphate insecticide, has the potential to cause neurotoxicity and pose human health hazards. In this study, an electrochemical enzyme biosensor based on Ti3C2 MXene/MoS2@AuNPs/AChE was constructed for the sensitive detection of phoxim. The two-dimensional multilayer structure of Ti3C2 MXene provides a robust framework for MoS2, leading to an expansion of the specific surface area and effectively preventing re-stacking of Ti3C2 MXene. Additionally, the synergistic effect of self-reduced grown AuNPs with MoS2 further improves the electrical conductivity of the composites, while the robust framework provides a favorable microenvironment for immobilization of enzyme molecules. Ti3C2 MXene/MoS2@AuNPs electrochemical enzyme sensor showed a significant response to phoxim in the range of 1 × 10-13 M to 1 × 10-7 M with a detection limit of 5.29 × 10-15 M. Moreover, the sensor demonstrated excellent repeatability, reproducibility, and stability, thereby showing its promising potential for real sample detection.


Subject(s)
Biosensing Techniques , Electrochemical Techniques , Fruit , Gold , Metal Nanoparticles , Nanocomposites , Organothiophosphorus Compounds , Titanium , Gold/chemistry , Electrochemical Techniques/instrumentation , Electrochemical Techniques/methods , Nanocomposites/chemistry , Fruit/chemistry , Metal Nanoparticles/chemistry , Biosensing Techniques/instrumentation , Organothiophosphorus Compounds/analysis , Titanium/chemistry , Limit of Detection , Food Contamination/analysis , Molybdenum/chemistry , Insecticides/analysis , Insecticides/chemistry , Pesticide Residues/analysis , Pesticide Residues/chemistry
11.
Food Chem ; 462: 140922, 2025 Jan 01.
Article in English | MEDLINE | ID: mdl-39213967

ABSTRACT

Rapid screening for foodborne pathogens is crucial for food safety. A rapid and one-step electrochemical sensor has been developed for the detection of Escherichia coli (E. coli), Staphylococcus aureus (S. aureus) and Salmonella typhimurium (S. typhimurium). Through the construction of aptamer/two-dimensional carboxylated Ti3C2Tx (2D C-Ti3C2Tx)/two-dimensional Zn-MOF (2D Zn-MOF) composites, the recognition elements, signal tags, and signal amplifiers are integrated on the electrode surface. Pathogens are selectively captured using the aptamer, which increases the impedance of the electrode surface,leads to a decrease in the 2D Zn-MOF current. Bacteria can be rapidly quantified using a one-step detection method and the replacement of aptamers. The detection limits for E. coli, S. aureus, and S. typhimurium are 6, 5, and 5 CFU·mL-1, respectively. The sensor demonstrated reliable detection capabilities in real-sample testing. Therefore, the one-step sensor based on the 2D Zn-MOF and 2D C-Ti3C2Tx has significant application value in the detection of foodborne pathogens.


Subject(s)
Electrochemical Techniques , Escherichia coli , Salmonella typhimurium , Staphylococcus aureus , Zinc , Staphylococcus aureus/isolation & purification , Salmonella typhimurium/isolation & purification , Zinc/analysis , Escherichia coli/isolation & purification , Electrochemical Techniques/instrumentation , Biosensing Techniques/instrumentation , Metal-Organic Frameworks/chemistry , Food Microbiology , Titanium/chemistry , Limit of Detection , Electrodes , Food Contamination/analysis
12.
Environ Sci Pollut Res Int ; 31(43): 55119-55131, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39245671

ABSTRACT

In this work, the photo-, electro-, and photo-electro-oxidation of chloramphenicol was investigated. The photo-experiments were carried out with different irradiation sources (an ultraviolet and a simulated solar source) using self-doped titanium nanotubes (SDTNT), a very promising and innovative material that deserves further investigations in the degradation of different pollutants. The photo-electrooxidation (j = 15 mA cm-2) under simulated solar irradiation presented the best efficiency, with ca. 100% degradation and kinetic constant of k = 0.04427 min-1. The FTIR analysis demonstrated a structural modification of the standard molecule occurred for all conditions used, suggesting a modification in functional groups responsible for the biological activity. Furthermore, the TOC analysis showed a significant mineralization of the pollutant (66% from the initial concentration). In addition, both photo-electrooxidation approaches have demonstrated a positive value of S, where the simulated solar irradiation reached the highest value S = 0.6960. The experimental results pointed out evidence that the methodology employed herein for chloramphenicol degradation is greatly interesting and the photo-electrooxidation under simulated solar irradiation is a promising approach for this purpose.


Subject(s)
Chloramphenicol , Nanotubes , Titanium , Chloramphenicol/chemistry , Titanium/chemistry , Nanotubes/chemistry , Oxidation-Reduction , Kinetics
13.
Int J Mol Sci ; 25(17)2024 Aug 23.
Article in English | MEDLINE | ID: mdl-39273096

ABSTRACT

In recent years, with the advent of a super-aged society, lifelong dental care has gained increasing emphasis, and implant therapy for patients with an edentulous jaw has become a significant option. However, for implant therapy to be suitable for elderly patients with reduced regenerative and immunological capabilities, higher osteoconductive and antimicrobial properties are required on the implant surfaces. Silicon nitride, a non-oxide ceramic known for its excellent mechanical properties and biocompatibility, has demonstrated high potential for inducing hard tissue differentiation and exhibiting antibacterial properties. In this study, silicon nitride was deposited on pure titanium metal surfaces and evaluated for its biocompatibility and antibacterial properties. The findings indicate that silicon nitride improves the hydrophilicity of the material surface, enhancing the initial adhesion of rat bone marrow cells and promoting hard tissue differentiation. Additionally, the antibacterial properties were assessed using Staphylococcus aureus, revealing that the silicon nitride-coated surfaces exhibited significant antibacterial activity. Importantly, no cytotoxicity was observed, suggesting that silicon nitride-coated titanium could serve as a novel implant material.


Subject(s)
Anti-Bacterial Agents , Coated Materials, Biocompatible , Silicon Compounds , Staphylococcus aureus , Surface Properties , Titanium , Titanium/chemistry , Titanium/pharmacology , Animals , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Coated Materials, Biocompatible/chemistry , Coated Materials, Biocompatible/pharmacology , Rats , Staphylococcus aureus/drug effects , Silicon Compounds/chemistry , Silicon Compounds/pharmacology , Materials Testing , Cell Adhesion/drug effects , Bone Marrow Cells/drug effects , Cell Differentiation/drug effects
14.
BMC Oral Health ; 24(1): 1077, 2024 Sep 12.
Article in English | MEDLINE | ID: mdl-39267015

ABSTRACT

NANOTECHNOLOGY: is the art and science of dealing with nanoscale particles. This has transformed contemporary dental practices through myriad contributions to biomaterial science. Titanium dioxide nanoparticles procured from Bacillus subtilis, an eco-friendly and biogenic source, can significantly magnify the physiochemical attributes of dental materials. However, postoperative sensitivity is a major drawback of composite restorations. The incorporation of these nanoparticles into dental adhesives can greatly benefit clinical dentistry by resolving this issue. This trial aimed to evaluate the effectiveness of a novel titanium dioxide nanofortified adhesive on the postoperative sensitivity of composite restorations. METHODS: This triple-blind, parallel-group randomized controlled trial was conducted at the Department of Operative Dentistry and Endodontics, School of Dentistry, Islamabad, from May 15, 2023, to November 25, 2023. Participants (n = 60) with Class I and II primary carious lesions with a minimum cavity depth of 3-5 mm were randomly assigned to two groups (n = 30). After obtaining informed consent, the restorative procedure was accomplished using a minimally invasive approach and etch-and-rinse adhesive strategy. In group A, a nanofortified adhesive was used for composite restoration, whereas in group B, an adhesive without nanoparticles was used. Postoperative sensitivity was evaluated using the Visual Analog Scale (VAS) score at follow-up periods: of one day, one week, two weeks and one month. A Chi-square test was used to compare postoperative sensitivity between the two groups. The level of significance was set at p < 0.05. RESULTS: A noteworthy association was observed between sensitivity and the group variable at all four evaluation periods: after one day (p = 0.002), 1 week (p = 0.002), 2 weeks (p = 0.007) and one month. In conclusion, participants who underwent restorative intervention using titanium dioxide nanoreinforced adhesives reported a notable reduction in sensitivity at all time intervals. Hence, the occurrence and severity of postoperative sensitivity are significantly reduced using Bacillus subtilis-procured nanofortified adhesives as compared to conventional adhesives without nanoparticles. TRIAL REGISTRATION: This trial was retrospectively registered at ClinicalTrials.gov (ID: NCT06242184) on 03/02/2024. All procedures involving human participants were performed in conformance with this protocol.


Subject(s)
Bacillus subtilis , Composite Resins , Dental Cements , Titanium , Humans , Bacillus subtilis/drug effects , Female , Male , Titanium/chemistry , Composite Resins/therapeutic use , Dental Cements/therapeutic use , Dentin Sensitivity/prevention & control , Nanoparticles , Dental Restoration, Permanent/methods , Dental Caries/prevention & control , Adolescent , Adult , Young Adult
15.
J Clin Pediatr Dent ; 48(5): 102-109, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39275826

ABSTRACT

Nickel-titanium (NiTi) instruments offer many advantages during endodontic instrumentation; however, the fracture risk within the canal remains a concern. Manufacturers continuously develop and introduce instruments to the market with supposedly enhanced cyclic fatigue resistance and increased flexibility, achieved through different proprietary manufacturing processes, the details of which have not been made public. In recent years, two rotary systems specially designed for deciduous teeth have been commercially available, but information about their performance is lacking. This investigation aimed to identify which manufacturing process provides better cyclic fatigue resistance: the AF-H Wire technology used in the AF baby rotary files (AF-f) or the CM-Wire technology used in the i3 Gold deciduous teeth rotary files (i3G-f). Forty rotary International Organization for Standardization (ISO) 25/04 files were tested in artificial canals with a standard geometry of 60° angle and 2.5 mm radius until fracture. The number of cycles to fracture was calculated, and the length of the fragments was measured. A scanning electron microscope (SEM) was used to examine the fracture surfaces and fragments. Energy dispersive spectroscopy (EDS) was used to determine the percentage weight of NiTi in each file. The statistical analysis (Mann-Whitney test) showed that the cyclic fatigue resistance of the AF-f was significantly higher (p < 0.0001) than that of the i3G-f. Additionally, there was a significant difference (p = 0.0419) in the length of the fractured fragments. All instruments showed one or more types of manufacturing defects and presented similar NiTi percentages by weight. The manufacturing process is critical to cyclic fatigue resistance, and there seems to be responsible for the difference in cyclic fatigue resistance between these similar instruments.


Subject(s)
Equipment Failure , Hot Temperature , Nickel , Root Canal Preparation , Titanium , Root Canal Preparation/instrumentation , Nickel/chemistry , Humans , Titanium/chemistry , Equipment Design , Materials Testing , Dental Instruments , Microscopy, Electron, Scanning , Dental Alloys/chemistry , In Vitro Techniques , Dental Stress Analysis
16.
Int J Mol Sci ; 25(17)2024 Sep 04.
Article in English | MEDLINE | ID: mdl-39273523

ABSTRACT

Amoxicillin (AMX) is utilized in the treatment of several infectious diseases, and its concentration in wastewater has increased quite significantly over the years, posing high health hazards for humans and other living organisms. Investigations are in progress globally to eliminate AMX and other related pollutants using several methods that include adsorption, photolysis, photocatalytic degradation, photoelectrocatalytic degradation, and electrochemical conversion. AMX can be eliminated efficiently from the environment using photodegradation, either by photolysis or a photocatalytic process. Several types of semiconductor NMs have been used to eliminate AMX and other related drugs present in wastewater. This review spans the photodegradation studies conducted during the years 2018-2024 to degrade and eliminate AMX in aquatic systems. Several studies have been reported to eliminate AMX from different water streams. These studies are categorized into TiO2-containing and non-TiO2-based catalysts for better comparison. A section on photolysis is also included, showing the use of UV alone or with H2O2 or PS without using any nanomaterial. A tabulated summary of both types of catalysts showing the catalysts, reaction conditions, and degradation efficiency is presented. Researchers have used a variety of reaction conditions that include radiation types (UV, solar, and visible), pH of the solution, concentration of AMX, number of nanomaterials, presence of other additives and activators such as H2O2 as oxidant, and the influence of different salts like NaCl and CaCl2 on the photodegradation efficiency. TiO2 was the best nanomaterial found that achieved the highest degradation of AMX in ultraviolet irradiation. TiO2 doped with other nanomaterials showed very good performance under visible light. WO3 was also used by several investigators and found quite effective for AMX degradation. Other metal oxides used for AMX elimination were derived from molybdenum, zinc, manganese, copper, cerium, silver, etc. Some researchers have used UV and/or visible irradiation or sunlight, without using solid catalysts, in the presence of oxidants such as H2O2. A summarized description of earlier published reviews is also presented.


Subject(s)
Amoxicillin , Photolysis , Water Pollutants, Chemical , Amoxicillin/chemistry , Water Pollutants, Chemical/chemistry , Catalysis , Hydrogen Peroxide/chemistry , Wastewater/chemistry , Ultraviolet Rays , Titanium/chemistry , Water Purification/methods , Anti-Bacterial Agents/chemistry
17.
Int J Mol Sci ; 25(17)2024 Sep 08.
Article in English | MEDLINE | ID: mdl-39273676

ABSTRACT

Microwaves have been successfully employed in the Lewis acid titanium tetrachloride-assisted synthesis of peptide systems. Dipeptide systems with their amino function differently protected with urethane protecting groups have been synthesized in short periods of time and with high yields. The formation of the peptide bond between the two reacting amino acids was achieved in pyridine by using titanium tetrachloride as a condensing agent and heating the reaction mixture with a microwave reactor. The reaction conditions are compatible with amino acids featuring various side chains and different protecting groups on both the amino function and side chains. Additionally, the substrates retain their chiral integrity after reaction.


Subject(s)
Dipeptides , Microwaves , Titanium , Dipeptides/chemistry , Dipeptides/chemical synthesis , Titanium/chemistry , Amino Acids/chemistry , Solutions
18.
Molecules ; 29(17)2024 Sep 03.
Article in English | MEDLINE | ID: mdl-39275012

ABSTRACT

Pharmaceuticals and personal care products (PPCPs) which include antibiotics such as tetracycline (TC) and ciprofloxacin (CIP), etc., have attracted increasing attention worldwide due to their potential threat to the aquatic environment and human health. In this work, a facile sol-gel method was developed to prepare tungsten-doped TiO2 with tunable W5+/W6+ ratio for the removal of PPCPs. The influence of solvents in the synthesis of the three different tungsten precursors doped TiO2 is also taken into account. WCl6, ammonium metatungstate (AMT), and Na2WO4●2H2O not only acted as the tungsten precursors but also controlled the tungsten ratio. The photocatalyst prepared by WCl6 as the tungsten precursor and ethanol as the solvent showed the highest photodegradation performance for ciprofloxacin (CIP) and tetracycline (TC), and the photodegradation performance for tetracycline (TC) was 2.3, 2.8, and 7.8 times that of AMT, Na2WO4●2H2O as the tungsten precursors and pristine TiO2, respectively. These results were attributed to the influence of the tungsten precursors and solvents on the W5+/W6+ ratio, sample crystallinity and surface properties. This study provides an effective method for the design of tungsten-doped TiO2 with tunable W5+/W6+ ratio, which has a profound impact on future studies in the field of photocatalytic degradation of PPCPs using an environmentally friendly approach.


Subject(s)
Cosmetics , Solvents , Titanium , Tungsten , Titanium/chemistry , Tungsten/chemistry , Catalysis , Solvents/chemistry , Cosmetics/chemistry , Photolysis , Ciprofloxacin/chemistry , Pharmaceutical Preparations/chemistry , Tetracycline/chemistry , Photochemical Processes , Water Pollutants, Chemical/chemistry
19.
Molecules ; 29(17)2024 Sep 03.
Article in English | MEDLINE | ID: mdl-39275029

ABSTRACT

Although titanium and its alloys are widely used as dental implants, they cannot induce the formation of new bone around the implant, which is a basis for the functional integrity and long-term stability of implants. This study focused on the functionalization of the titanium/titanium oxide surface as the gold standard for dental implants, with electrospun composite fibers consisting of polyvinylpyrrolidone and Ca2+ ions. Polymer fibers as carriers of Ca2+ ions should gradually dissolve, releasing Ca2+ ions into the environment of the implant when it is immersed in a model electrolyte of artificial saliva. Scanning electron microscopy, energy dispersive X-ray spectroscopy and attenuated total reflectance Fourier transform infrared spectroscopy confirmed the successful formation of a porous network of composite fibers on the titanium/titanium oxide surface. The mechanism of the formation of the composite fibers was investigated in detail by quantum chemical calculations at the density functional theory level based on the simulation of possible molecular interactions between Ca2+ ions, polymer fibers and titanium substrate. During the 7-day immersion of the functionalized titanium in artificial saliva, the processes on the titanium/titanium oxide/composite fibers/artificial saliva interface were monitored by electrochemical impedance spectroscopy. It can be concluded from all the results that the composite fibers formed on titanium have application potential for the development of osteoinductive and thus more biocompatible dental implants.


Subject(s)
Calcium , Dental Implants , Titanium , Titanium/chemistry , Calcium/chemistry , Calcium/metabolism , Povidone/chemistry , Humans , Ions/chemistry , Spectroscopy, Fourier Transform Infrared , Saliva, Artificial/chemistry , Biocompatible Materials/chemistry , Spectrometry, X-Ray Emission , Osteogenesis/drug effects
20.
Mikrochim Acta ; 191(10): 613, 2024 Sep 21.
Article in English | MEDLINE | ID: mdl-39305316

ABSTRACT

The electrochemical detection characteristics of the layered Ti3C2Tx material were enhanced by modifying its surface. Ti3C2Tx is used as the Ti - F chemical bond weakens with increasing pH levels. Ti3C2Tx is alkalinized by KOH, and F is substituted for - OH. The surface hydroxyl groups can be eliminated by intercalating K+. This study elaborates on the hydrothermal production of vanadium-doped layered Ti3C2Tx nanosheets intercalated with K+. The development of a sensitive dopamine electrochemical sensor is outlined by intercalating a vanadium-doped multilayered K+ Ti3C2Tx electrode. The chemical, surface, and structural composition of the synthesized electrode for dopamine detection was investigated and confirmed. The sensor exhibits a linear range (1-10 µM), a low detection limit (8.4 nM), and a high sensitivity of 2.746 µAµM-1cm-2 under optimal electrochemical testing conditions. The sensor also demonstrates exceptional anti-interference capabilities and stability. The sensor was applied to detection of dopamine in (spiked) rat brains, human serum, and urine samples. This study introduces a novel approach by utilizing K+ intercalation of vanadium-doped Ti3C2Tx-based electrochemical sensors and an innovative method for dopamine detection. The dopamine detection revealed the potential of (V0.05) K+ Ti3C2Tx-GCE for practical application in pharmaceutical sample analysis.


Subject(s)
Dopamine , Electrochemical Techniques , Electrodes , Limit of Detection , Titanium , Vanadium , Dopamine/urine , Dopamine/blood , Dopamine/analysis , Vanadium/chemistry , Titanium/chemistry , Animals , Electrochemical Techniques/methods , Rats , Humans , Potassium/blood , Potassium/urine , Potassium/chemistry
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