Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 321
Filter
1.
J Hazard Mater ; 480: 136041, 2024 Oct 02.
Article in English | MEDLINE | ID: mdl-39368359

ABSTRACT

Effective removal of mercury (Hg) from wastewater is significant due to its high toxicity, especially methylmercury (MeHg). Reducing of Hg(II) to Hg(0) in constructed wetlands (CWs) using iron-based materials is an effective strategy for preventing the formation of MeHg. However, the surface passivation of zero-valent iron (ZVI) limits its application. Herein, synergetic ZVI and pyrrhotite were utilized to enhance Hg removal in CWs. Results indicated that the removal of total Hg, dissolved Hg, and particulate Hg in CWs with ZVI and pyrrhotite were improved by 21.68 ± 0.76 %, 13.02 ± 0.88 %, and 22.27 ± 0.76 % compared to that with single ZVI or pyrrhotite. Pyrrhotite increased the surface corrosion of ZVI, thereby facilitating the process of iron reduction. The redox of iron promoted the generation of EPS, which could provide electrons for Hg(II) reduction. The sulfur also participates in electron transfer by driving the methylation of Hg and provides sulfides to form FeS-Hg complexes and HgS precipitation. The abundance of key enzymes that involved in iron reduction and Hg transformation was enhanced with the addition of ZVI and pyrrhotite. The synergetic of pyrrhotite and ZVI enhances the removal of Hg in CW, offering a promising technology for high-efficiency treatment of Hg.

2.
Zhongguo Zhong Yao Za Zhi ; 49(17): 4658-4671, 2024 Sep.
Article in Chinese | MEDLINE | ID: mdl-39307804

ABSTRACT

The preparation processes of iron-based organic framework(FeMOF) MIL-100(Fe) and MIL-101(Fe) with two different ligands were optimized and screened, and the optimized FeMOF was loaded with piperlongumine(PL) to enhance the biocompatibility and antitumor efficacy of PL. The MIL-100(Fe) and MIL-101(Fe) were prepared by solvent thermal method using the optimized reaction solvent. With particle size, polymer dispersity index(PDI), and yield as indexes, the optimal preparation processes of the two were obtained by using the definitive screening design(DSD) experiment and establishing a mathematical model, combined with the Derringer expectation function. After characterization, the best FeMOF was selected to load PL by solvent diffusion method, and the process of loading PL was optimized by a single factor combined with an orthogonal experiment. The CCK-8 method was used to preliminarily evaluate the biological safety of blank FeMOF and the antitumor effect of the drug-loaded nano preparations. The experimental results showed that the optimal preparation process of MIL-100(Fe) was as follows: temperature at 127.8 ℃, reaction time of 14.796 h, total solvent volume of 11.157 mL, and feed ratio of 1.365. The particle size of obtained MIL-100(Fe) nanoparticles was(108.84±2.79)nm; PDI was 0.100±0.023, and yield was 36.93%±0.79%. The optimal preparation process of MIL-101(Fe) was as follows: temperature at 128.1 ℃, reaction time of 6 h, total solvent volume of 10.005 mL, and feed ratio of 0.500. The particle size of obtained MIL-101(Fe) nanoparticles was(254.04±22.03)nm; PDI was 0.289±0.052, and yield was 44.95%±0.45%. The optimal loading process of MIL-100(Fe) loaded with PL was as follows: the feed ratio of MIL-100(Fe) to PL was 1∶2; the concentration of PL solution was 7 mg·mL~(-1), and the ratio of DMF to water was 1∶5. The drug loading capacity of obtained MIL-100(Fe)/PL nanoparticles was 68.86%±1.82%; MIL-100(Fe) was nontoxic to HepG2 cells at a dose of 0-120 µg·mL~(-1), and the half-inhibitory concentration(IC_(50)) of free PL for 24 h treatment of HepG2 cells was 1.542 µg·mL~(-1). The IC_(50) value of MIL-100(Fe)/PL was 1.092 µg·mL~(-1)(measured by PL). In this study, the optimal synthesis process of MIL-100(Fe) and MIL-101(Fe) was optimized by innovatively using the DSD to construct a mathematical model combined with the Derringer expectation function. The optimized preparation process of MIL-100(Fe) nanoparticles and the PL loading process were stable and feasible. The size and shape of MIL-100(Fe) particles were uniform, and the crystal shape was good, with a high drug loading capacity, which could significantly enhance the antitumor effect of PL. This study provides a new method for the optimization of the nano preparation process and lays a foundation for the further development and research of antitumor nano preparations of PL.


Subject(s)
Antineoplastic Agents , Dioxolanes , Iron , Metal-Organic Frameworks , Humans , Dioxolanes/chemistry , Metal-Organic Frameworks/chemistry , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Iron/chemistry , Cell Line, Tumor , Particle Size , Nanoparticles/chemistry , Drug Carriers/chemistry , Cell Survival/drug effects , Drug Compounding/methods , Cell Proliferation/drug effects , Piperidones
3.
Small ; : e2406424, 2024 Sep 25.
Article in English | MEDLINE | ID: mdl-39319492

ABSTRACT

Inexpensive iron-based materials are considered promising electrocatalysts for nitrate (NO3 -) reduction, but their catalytic activity and spontaneous corrosion remain challenges. Here, the α-Fe2O3 active surface is reconstructed by gradient phosphorization to obtain FePx with higher electrochemical activity. FeP2.0 optimizes the adsorption energy of NO3 - and its reduction intermediates, meanwhile promote the generation of active hydrogen (*H) but inhibit its generation of H2. More importantly, Fe and P can serve as binding sites for NO3 - and *H, respectively, which improves the electron utilization of NO3 - deoxygenation and the efficiency of the subsequent hydrogenation for the selective synthesis of NH3. 91.7% NO3 - conversion rate is achieved for the reduction of 100 mL 200 mg L-1 NO3 --N, 99.3% ammonia (NH3 selectivity (yield of 1.79 mg h-1 cm-2), and 91.4% Faraday efficiency in 3 h. The high-purity solid NH4Cl is finally extracted by gas extraction and vacuum distillation (81.4% recovery). This study provides new insights and strategies for the conversion of NO3 - to NH3 products over iron-based electrocatalysts.

4.
Chemosphere ; 364: 143240, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39222696

ABSTRACT

Iron(II)-based metal organic framework (Fe(II)-MOF) nanosheets have emerged as promising candidates for photo-Fenton catalysis. However, efficiently synthesizing Fe(II)-MOF nanosheets remains a significant challenge. Here, a bottom-up synthesis strategy is proposed to prepare two-dimensional Fe-MOF nanosheets (TFMN) with micrometer lateral dimensions and nanometer thickness, featuring Fe(II) as the metal nodes. The application of TFMN in the photo-Fenton degradation of carbamazepine (CBZ) demonstrates remarkable CBZ degradation performance and excellent efficiency across a wide range of pH values. The electron density and density of states are further calculated by density functional theory. Mechanism analysis identifies h+, •OH and •O2- as the predominant active species contributing to the catalytic oxidation process in the Vis/TFMN/H2O2 system.


Subject(s)
Carbamazepine , Hydrogen Peroxide , Iron , Metal-Organic Frameworks , Nanostructures , Oxidation-Reduction , Carbamazepine/chemistry , Metal-Organic Frameworks/chemistry , Hydrogen Peroxide/chemistry , Iron/chemistry , Catalysis , Nanostructures/chemistry , Water Pollutants, Chemical/chemistry
5.
Sci Total Environ ; 953: 176128, 2024 Nov 25.
Article in English | MEDLINE | ID: mdl-39255942

ABSTRACT

This review explores the expanding role of electrochemical sensors across diverse domains such as environmental monitoring, medical diagnostics, and food quality assurance. In recent years, iron-based electrocatalysts have emerged as promising candidates for enhancing sensor performance. Notable for their non-toxicity, abundance, catalytic activity, and cost-effectiveness, these materials offer significant advantages. However, further investigation is needed to fully understand how iron-based materials' physical, chemical, and electrical properties influence their catalytic performance in sensor applications. It explores the overview of electrochemical sensor technology, examines the impact of iron-based materials and their characteristics on catalytic activity, and investigates various iron-based materials, their advantages, functionalization, and modification techniques. Additionally, the review investigates the application of iron-based electrode material composites in electrochemical sensors for real sample detections. Ultimately, continued research and development in this area promise to unlock new avenues for using iron-based electrode materials in sensor applications.

6.
Sensors (Basel) ; 24(17)2024 Aug 23.
Article in English | MEDLINE | ID: mdl-39275377

ABSTRACT

Developing long-lasting humidity sensors is essential for sustainable advancements in nanotechnology. Prolonged exposure to high humidity can cause sensors to drift from their calibration points, leading to long-term accuracy issues. Our research aims to develop a fabrication method that produces stable sensors capable of withstanding the environmental challenges faced by humidity sensors. Traditional iron-based nanoparticles often require complex treatments, such as chemical modification or thermal annealing, to maintain their properties. This study introduces a novel, one-step synthesis method for iron-based thin films with exceptional stability. The synthesized films were thoroughly characterized using X-ray photoelectron spectroscopy (XPS) to evaluate their phase stability and nitride formation. The method proposed in this study employs an electrical sparking discharge process within a pure nitrogen atmosphere under a 0.2 T magnetic field, producing thin films composed of nanoparticles approximately 20 nm in size. The resulting films demonstrate superior performance in humidity sensing applications compared to conventional methods. This straightforward and efficient approach offers a promising path toward robust and sustainable humidity sensors.

7.
Biomater Adv ; 166: 214038, 2024 Sep 08.
Article in English | MEDLINE | ID: mdl-39306963

ABSTRACT

To address the issue of high-dose treatment agents in magnetic hyperthermia-mediated multi-model tumor therapy, a unique iron-based theranostic nanoenzyme with excellent magnetothermal and catalytic properties was constructed. By using a high-temperature arc method, the iron carbon nanoparticles (MF1-3) with a particle size between 13.7 and 27.6 nm and shell thickness between 1 and 5 nm were prepared. After screening, we selected MF3 as the magnetic core due to its high Ms. value and excellent thermal properties. Under the magneto-photo dual thermal conditions, MF3 exhibited a remarkable specific absorption rate (SAR) of 4917 W/g, which was 20 times more than that of iron oxide. Notably, MF3 also exhibited best peroxidase (POD)-like catalytic in pH 5.0 and maintained stable catalytic performance at 45 °C. Considering the "starvation" strategy of cutting off the energy supply to tumor cells and killing them, the glucose oxidase (GOX) and chitosan oligosaccharide (COS) was further grafted onto MF3, forming the MF3/GOX/COS. This multifunctional therapeutic nanoenzyme not only exhibited significant peroxidase-like activity, but also had glucose decomposition and glutathione (GSH) consumption capabilities. The thermal effect significantly promoted the uptake of MF3/GOX/COS by 4T1 cells, and the IC50 value of MF3/GOX/COS reached low to 3.75 µg/mL. In vivo anti-tumor experiment, compared with single treatment methods, the combined therapy of MF3/GOX/COS mediated magneto-photo thermotherapy (M-PTT) and starvation therapy (ST) exhibited higher tumor inhibition rate of 82.1 % by increased cell apoptosis through the mitochondrial pathway. Overall, MF3/GOX/COS therapeutic nanoenzyme combined the advantages of nano-catalysis, M-PTT and ST, providing a solution for achieving sustained, stable, and effective tumor inhibition rates at lower dose levels.

8.
Materials (Basel) ; 17(16)2024 Aug 21.
Article in English | MEDLINE | ID: mdl-39203320

ABSTRACT

In this paper, the precipitation behavior and its effect on resistivity in a new type of nickel-iron-based alloy during short-term aging were investigated. During the aging process, the γ' phase increases in average size and decreases in number, with its area fraction fluctuating over time. This fluctuation is caused by the mismatch in the redissolution and growth rates of the γ' phase. As the area fraction of the γ' phase increases, the content of solute atoms in the matrix that scatter electrons decreases, lowering the resistivity of the alloy. Additionally, the continuous precipitation of M23C6 at grain boundaries during aging causes the resistivity to gradually increase. This paper explains the fluctuation in the total amount of γ' phase during short-term aging and proposes a new method for characterizing the precipitation behavior of the γ' phase in the novel alloy using the relative trend of resistivity changes.

9.
Environ Sci Pollut Res Int ; 31(39): 52615-52627, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39158657

ABSTRACT

Developing highly effective iron-based catalyst to selectively remove organic contaminants has garnered considerable attention. Herein, a magnetic Fe0/FeS2-doped carbon nanolayer (S-Fe@NC) was synthesized through a straightforward one-step pyrolysis method, pyrolyzing a mixture composed of 4,6-dihydroxypyrimidine, trithiocyanuric acid, and FeCl3·6H2O. With the presence of PMS, S-Fe@NC demonstrated the ability to remove almost 100% bisphenol-A (50 µM) within 3 min, attributed to its excellent graphitization degree and high FeS2/Fe0 content. Furthermore, the S-Fe@NC catalyst demonstrated an impressive kobs value of 1.476 min-1, which surpassed the traditional Fenton system by 77 times and even exceeded the commercial Fe0 catalyst by 127 times. More importantly, the S-Fe@NC/PMS system succeeded in selectively removing organic contaminants based on the hydrophobic interaction between catalyst and contaminants. Besides, the result of electron paramagnetic resonance and the radical quenching experiments indicated that ·OH, SO4·-, 1O2, and O2·- were involved in the organic contaminants removal. Interestingly, after adding ascorbic acid (AA) to the S-Fe@NC/PMS system, more ROS could be generated to result in the kobs augmenting by 4.16 times (6.133 min-1), completely different from the common sense that AA was usually used as a radical quencher. Additionally, the magnetically separable catalyst also exhibited excellent reusability and broad pH adaptability (2.0-12.0). This study provided a valuable insight for developing highly selective and effective Fe-based catalyst for practical wastewater treatment.


Subject(s)
Ascorbic Acid , Carbon , Ascorbic Acid/chemistry , Carbon/chemistry , Catalysis , Iron/chemistry , Water Pollutants, Chemical/chemistry , Benzhydryl Compounds/chemistry , Phenols
10.
Nanomaterials (Basel) ; 14(15)2024 Aug 05.
Article in English | MEDLINE | ID: mdl-39120424

ABSTRACT

The iron-based superconductors (IBSs) of the recently discovered 1144 class, unlike many other IBSs, display superconductivity in their stoichiometric form and are intrinsically hole doped. The effects of chemical substitutions with electron donors are thus particularly interesting to investigate. Here, we study the effect of Co substitution in the Fe site of CaKFe4As4 single crystals on the critical temperature, on the energy gaps, and on the superfluid density by using transport, point-contact Andreev-reflection spectroscopy (PCARS), and London penetration depth measurements. The pristine compound (Tc≃36 K) shows two isotropic gaps whose amplitudes (Δ1 = 1.4-3.9 meV and Δ2 = 5.2-8.5 meV) are perfectly compatible with those reported in the literature. Upon Co doping (up to ≈7% Co), Tc decreases down to ≃20 K, the spin-vortex-crystal order appears, and the low-temperature superfluid density is gradually suppressed. PCARS and London penetration depth measurements perfectly agree in demonstrating that the nodeless multigap structure is robust upon Co doping, while the gap amplitudes decrease as a function of Tc in a linear way with almost constant values of the gap ratios 2Δi/kBTc.

11.
Water Res ; 263: 122149, 2024 Oct 01.
Article in English | MEDLINE | ID: mdl-39098153

ABSTRACT

Sulfidated nanoscale zerovalent iron (S-nZVI) has demonstrated promising reactivity and longevity for remediating chlorinated volatile compounds (cVOC) contaminants in laboratory tests. However, its effectiveness in field applications remains inadequately evaluated. This study provides the first quantitative evaluation of the long-term effectiveness of carboxymethyl cellulose-stabilized S-nZVI (CMC-S-nZVI) at a cVOC-contaminated field site. A reactive transport model-based numerical approach delineates the change in cVOC concentrations and carbon isotope values (i.e., δ13C from compound-specific stable isotope analysis (CSIA)) caused by dissolution of dense non-aqueous phase liquid, sorption, and pathway-specific degradation and production, respectively. This delineation reveals quantitative insights into remediation effectiveness typically difficult to obtain, including extent of degradation, contributions of different degradation pathways, and degradation rate coefficients. Significantly, even a year after CMC-S-nZVI application, degradation remains an important process effectively removing various cVOC contaminants (i.e., chlorinated ethenes, 1,2-dichloroethanes, and chlorinated methanes) at an extent varying from 5 %-62 %. Although the impacts of CMC-S-nZVI abundance on degradation vary for different cVOC and for different sampling locations at the site, for the primary site contaminants of tetrachloroethene and trichloroethene, their predominance of dichloroelimination pathway (≥ 88 %), high degradation rate coefficient (0.4-1.7 d-1), and occurrence at locations with relatively high CMC-S-nZVI abundance strongly indicate the effectiveness of abiotic remediation. These quantitative assessments support that CMC-S-nZVI supports sustainable ZVI-based remediation. Further, the novel numerical approach presented in this study provides a powerful tool for quantitative cVOC remediation assessments at complex field sites where multiple processes co-occur to control both concentration and CSIA data.


Subject(s)
Environmental Restoration and Remediation , Iron , Iron/chemistry , Environmental Restoration and Remediation/methods , Volatile Organic Compounds/chemistry , Hydrocarbons, Chlorinated/chemistry , Water Pollutants, Chemical/chemistry , Carbon Isotopes , Models, Theoretical
12.
Small ; : e2406033, 2024 Aug 26.
Article in English | MEDLINE | ID: mdl-39185806

ABSTRACT

Spent graphite, as the main component of retired batteries, have attracted plenty of attentions. Although a series of recycling strategies are proposed, they still suffer from high cost of regeneration and large CO2 emission, mainly ascribed to the full-recovery of surface and internal phase at ultra-high temperature. However, the existing of suitable internal defects is conductive to their energy-storage abilities. Herein, with the introduction of Fe-based catalysts, spent graphite is successfully repaired at low temperature with the tailored surface traits, including conductivities, isotropy and so on. As Li-storage anodes, all of samples can display a capacity of 340 mAh g-1 above at 1.0 C after 200 cycles. At high rate 5.0 C, their capacity can be also kept ≈300 mAh g-1, and remained ≈233 mAh g-1 even after 1000 cycles. Assisted by electrochemical and kinetic behaviors, their cycling traits with dynamic surface transformations are detailed explored, including activated/fading mechanism, Li-depositions forming etc. Moreover, the calculated constant time of as-optimized regenerated sample is ≈3.0 × 10-4 s, further revealing the importance of surface designing. Therefore, the work is expected to shed light on their energy-storage behaviors, and offer low-temperature regenerated strategies of spent graphite with high value.

13.
J Phys Condens Matter ; 36(47)2024 Aug 30.
Article in English | MEDLINE | ID: mdl-39142344

ABSTRACT

We have investigated the local structure of the iron-based CaKFe4As4superconductor featuring distinct aliovalent substitutions at the Ca and K sites, that is CaKFe4As4, CaK0.9Sr0.1Fe4As4, CaK0.9Ba0.1Fe4As4and Ca0.9Na0.1K0.9Ba0.1Fe4As4. Temperature-dependent Fe K-edge extended x-ray absorption fine structure (EXAFS) measurements are used to determine the near-neighbors bondlengths and their stiffness. The EXAFS analysis reveals that the Fe-As bondlength undergoes negligible changes by substitution, however, the Fe-Fe bondlength and the As height are affected by the Sr substitution. The superconducting transition temperatures of CaK0.9Sr0.1Fe4As4and CaK0.9Ba0.1Fe4As4are very similar even if the mean As heights are significantly different suggesting that the anion height may not be a unique parameter to describe the superconductivity in CaKFe4As4. The mean As heights show a peculiar temperature dependence characteristic of CaKFe4As4system. Furthermore, the temperature-dependent mean square relative displacements reveal similar Fe-Fe bond stiffness in all samples, instead the Fe-As bond is substantially stiffer in case of CaK0.9Sr0.1Fe4As4. The local structure results are discussed in relation to the differing transport properties of aliovalent substituted 1144 superconductor.

14.
Water Res ; 264: 122255, 2024 Oct 15.
Article in English | MEDLINE | ID: mdl-39153313

ABSTRACT

Chemical oxidation is extensively utilized to mitigate the impact of organic pollutants in wastewater. The non-radical oxidation driven by iron-based materials is noted for its environmental friendliness and resistance to wastewater matrix, and it is a promising approach for practical wastewater treatment. However, the complexity of heterogeneous systems and the diversity of evolutionary pathways make the mechanisms of non-radical oxidation driven by iron-based materials elusive. This work provides a systematic review of various non-radical oxidation systems driven by iron-based materials, including singlet oxygen (1O2), reactive iron species (RFeS), and interfacial electron transfer. The unique mechanisms by which iron-based materials activate different oxidants (ozone, hydrogen peroxide, persulfate, periodate, and peracetic acid) to produce non-radical oxidation are described. The roles of active sites and the unique structures of iron-based materials in facilitating non-radical oxidation are discussed. Commonly employed identification methods in wastewater treatment are compared, such as quenching, chemical probes, spectroscopy, mass spectrometry, and electrochemical testing. According to the process of iron-based materials driving non-radical oxidation to remove organic pollutants, the driving factors at different stages are summarized. Finally, challenges and countermeasures are proposed in terms of mechanism exploration, detection methods and practical applications of non-radical oxidation driven by iron-based materials. This work provides valuable insights for understanding and developing non-radical oxidation systems.


Subject(s)
Iron , Oxidation-Reduction , Waste Disposal, Fluid , Wastewater , Wastewater/chemistry , Iron/chemistry , Waste Disposal, Fluid/methods , Water Purification/methods , Water Pollutants, Chemical/chemistry
15.
J Hazard Mater ; 479: 135692, 2024 Nov 05.
Article in English | MEDLINE | ID: mdl-39213775

ABSTRACT

Low H2O2 production, narrow adaptive pH range and slow Fe(II) regeneration on the cathode still limit efficiency of electro-Fenton (EF) and its application. Herein, we designed a bifunctional catalyst with FeS and Fe3O4 nanoparticles dispersed on porous carbon (CFeS@C) using template of sodium alginate (SA)/FeSO4 hydrogel mixed with carbon black (CB), which presented high H2O2 generation efficiency and outstanding tetracycline degradation efficiency under wide pH ranges (3-8) with a low energy consumption of 19.6 kWh/kg total organic carbon (TOC). The introduction of CB created abundant oxygen vacancies in CFeS@C, promoting the oxygen adsorption and the electrochemical generation of H2O2, which further boosted the formation of •OH due to the interaction with Fe2+ on the cathode surface. Simultaneously, the reaction between the outer layer of FeS and Fe3+ not only accelerated iron cycling but also reduced the solution pH. It was verified that •OH and 1O2 played a dominant role in organics degradation. The system maintained stability after 10 cycles and effectiveness in the treatment of pharmaceutical wastewater. This study would offer a new strategy to develop an efficient and durable bifunctional catalyst for heterogeneous EF system working in wide pH conditions for wastewater treatment.

16.
ChemSusChem ; : e202400252, 2024 Jul 30.
Article in English | MEDLINE | ID: mdl-39078603

ABSTRACT

Designing metal nanoparticles with oxidase-mimicking capabilities has garnered significant attention due to their promising attributes. However, understanding the intricate catalytic mechanisms underlying these nanoparticles poses a formidable challenge. In this study, a straightforward pyrolysis procedure was employed to synthesize nitrogen-doped iron-based nanoparticles (Fe NPs-N@C) with Fe8-N2 serving as active sites. The confirmation of these sites was thoroughly confirmed through density functional theory (DFT) calculations complemented by experimental validation. The resulting Fe NPs-N@C nanoparticles, averaging 5.45 nm in size, exhibited excellent oxidase-mimicking activity, with vmax=1.11×10-7 M s-1and km=1.67 mM, employing 3,3',5,5'-tetramethylbenzidine as a substrate. The oxidation pathway and catalytic mechanism of Fe NPs-N@C involved 1O2⋅ radicals, validated through electron paramagnetic resonance analysis and DFT calculations. Furthermore, Fe NPs-N@C/TMB system was devised for ascorbic acid and nitrite quantitative detection. This method demonstrated the capability to detect ascorbic acid within concentrations ranging from 1 to 55 µM, with a limit of detection (LOD) of 0.81 µM, and nitrite within concentrations from 1 to 160 µM, with a LOD value of 0.45 µM. These findings offer a comprehensive understanding of the catalytic mechanisms of Fe NPs-N@C nanoparticles at the atomic level, along with its potential for colorimetric sensor in future.

17.
Macromol Rapid Commun ; : e2400270, 2024 Jul 29.
Article in English | MEDLINE | ID: mdl-39072921

ABSTRACT

Microwave-assisted pyrolysis of PE to hydrogen and carbon material has great potential to solve the problem of waste PE induced white pollution and provide a promising way to produce hydrogen energy. To increase the hydrogen yield, a new microwave-assisted pyrolysis procedure should be developed. In the present study, a facile double-layer microwave-assisted pyrolysis (DLMP) method is developed to pyrolyze PE. Within this method, PE can be converted to hydrogen, multiwalled carbon nanotubes with extremely high efficiency compared with the traditional methods. A high hydrogen yield of 66.4 mmol g-1 PE is achieved, which is ≈93% of the upper limit of the theoretical hydrogen yield generated from the PE pyrolysis process. The mechanism of high hydrogen yield during the microwave-assisted pyrolysis of PE using the DLMP method is also clarified in detail. The DLMP method paved the potential way for recycling plastic waste into high-value-added products.

18.
Sci Total Environ ; 948: 174719, 2024 Oct 20.
Article in English | MEDLINE | ID: mdl-39019270

ABSTRACT

This research assesses the efficacy of two phosphorus (P) adsorbents as alternative fertilizers in promoting lettuce growth. A synthetic Mg/Al-layered double hydroxide (LDH) and an iron-based recycled water treatment residual (Fe-WTR), both enriched with P from dairy wastewater and added at three dosage levels. We hypothesized that the adsorbents' physicochemical nature will overshadow the biological efforts in the plant ecosystem to increase P solubility, impacting plant growth, nutritional composition, and metabolite profiles. Fe-WTR significantly enhanced lettuce biomass compared to LDH. Yet, elemental analysis revealed higher or equal P concentrations in the low-biomass LDH plants relative to other treatments. Phosphorus uptake appears to influence the assimilation of other nutrients that divided into two groups: calcium, magnesium, zinc, and copper with notable correlations to P and nitrogen, iron, aluminum, vanadium and manganese with low correlations to P. Conversely, P retained poor correlation with most metabolites whereas iron showed a higher correlation with numerous metabolites. Analysis of metabolites, encompassing carbohydrates, the Krebs cycle, amino acids, nucleic acids, and stress and regulatory pathways, revealed diminished levels in the LDH treatments. Overall, carbon assimilation (plant growth) was more effectively predicted by soil P availability (adsorbent type and dose) rather than by cellular P concentration, suggesting root signaling was at play, influencing carbohydrate translocation to the roots. Diminished levels of cellular sugars further affect metabolic pathways and iron uptake, thus restricting photosynthesis. The results illustrate the substantial influence of the P source on the plant's metabolic processes and soil biogeochemistry. The synthetic LDH adsorbent with high sorption capacity, tightly binds its substantial P pool, rendering it inaccessible and potentially disrupting rhizosphere biogeochemical interactions. In contrast, the chemical nature of Fe-WTR enabled efficient nutrients acquisition bioactivity. The study highlights Fe-WTR as a promising sustainable alternative to conventional fertilizers, emphasizing its potential scalability and adaptability in agricultural contexts.


Subject(s)
Agriculture , Lactuca , Phosphorus , Soil , Lactuca/growth & development , Lactuca/metabolism , Agriculture/methods , Soil/chemistry , Fertilizers , Recycling
19.
Chempluschem ; : e202400327, 2024 Jul 16.
Article in English | MEDLINE | ID: mdl-39012805

ABSTRACT

CO2 conversion via hydrogenation on iron-based catalysts on non-carbon supports produces mainly CO or methane by the Sabatier reaction, while the formation of C2+ hydrocarbons is of greatest interest. CxHy production from CO2 may be considered as a two-step process with the initial formation of carbon monoxide by the reverse water gas shift reaction followed by the Fischer-Tropsch synthesis (FTS). In the present work CO2 hydrogenation over iron-based catalysts (Fe, FeCr, FeK) deposited on a carbon carrier has been studied. The catalyst structure has been investigated by XRD, TEM, XPS, Mössbauer spectroscopy and in situ magnetometry. Spinel-type oxide phases (magnetite Fe3O4; maggemite γ-Fe2O3, and, in the case of FeCr/C catalyst, iron chromite Fe1+xCr2-xO4) are formed on the catalysts, and they contribute exclusively to the CO production. Iron carbides, active in FTS, are formed on Fe- and FeK-catalysts during pre-activation in reducing environment and then during the reaction. The reaction over the 20Fe1K/C catalyst in supercritical high-density CO2/H2 substrate (400°C, 8.5 MPa) leads to 72% selectivity for C1-C12+ hydrocarbons (alkanes and alkenes). Under the same conditions, iron carbides do not form on the FeCr/C catalysts, and CO2 hydrogenation results in the CO formation with the selectivity of 90-100%.

20.
Materials (Basel) ; 17(13)2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38998143

ABSTRACT

Iron-chalcogenide superconductors continue to captivate researchers due to their diverse crystalline structures and intriguing superconducting properties, positioning them as both a valuable platform for theoretical investigations and promising candidates for practical applications. This review begins with a comprehensive overview of the fabrication techniques employed for various iron-chalcogenide superconductors, accompanied by a summary of their phase diagrams. Subsequently, it delves into the upper critical field, anisotropy, and critical current density. Furthermore, it discusses the successful fabrication of meters-long coated conductors and explores their applications in superconducting radio-frequency cavities and coils. Finally, several prospective avenues for future research are proposed.

SELECTION OF CITATIONS
SEARCH DETAIL