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1.
PLoS One ; 19(3): e0295938, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38466758

RESUMO

In order to solve the problem that the skid resistance of concrete pavement in tunnel deteriorates rapidly, which is easy to cause traffic accidents, the anti-skid rapid elevation technology of surface treatment is proposed. Wear tests were used to investigate the effects of concrete surface roughness, properties of modified emulsified asphalt binder and anti-skid fine aggregate type on long-term skid resistance of treated surfaces. The results show that the four coarsening methods of fine milling, milling, grooving and brooming can improve the skid resistance of concrete, and the skid resistance durability of fine milling and milling is better. The adhesive property of modified emulsified asphalt is the best when the content of water-based epoxy resin is 20%. In different aggregates, the anti-skid effect is better when silicon carbide is used as anti-skid aggregate and the particle size is 0.6mm:0.3mm = 2:3. The method of fine milling of concrete surface + spraying epoxy emulsified asphalt + spreading silicon carbide can effectively improve the anti-skid performance of the original concrete pavement, and the feasibility of the scheme is verified by the test road. The research results have a good reference value for improving the skid resistance of tunnel concrete pavement.


Assuntos
Acidentes de Trânsito , Compostos Inorgânicos de Carbono , Hidrocarbonetos , Compostos de Silício , Tamanho da Partícula
2.
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
3.
J Environ Manage ; 352: 120037, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38194872

RESUMO

Herbicide abuse has a significantly negative impact on soil microflora and further influences the ecological benefit. The regulating measures and corresponding mechanisms mitigating the decreased bacterial diversity due to herbicide use have rarely been studied. A field experiment containing the application gradient of an efficient maize herbicide thiencarbazone-methyl·isoxaflutole was performed. The relationship between soil bacterial community and thiencarbazone-methyl·isoxaflutole use was revealed. Modified attapulgite was added to explore its impacts on soil microflora under the thiencarbazone-methyl·isoxaflutole application. Based on the analytic network process-entropy weighting method-TOPSIS method model, the ecological benefit focusing on microbial responses was quantitatively estimated along with technical effectiveness and economic benefit. The results showed that the diversity indices of soil microflora, especially the Inv_Simpson index, were reduced at the recommended, 5 and 10 times the recommended dosages of thiencarbazone-methyl·isoxaflutole use. The Flavisolibacter bacteria was negatively correlated with the residues in soils based on the random forest model and correlation analysis, indicating a potential degrader of thiencarbazone-methyl·isoxaflutole residues. The structural equation model further confirmed that the high soil water content and soil pH promoted the function of Flavisolibacter bacteria, facilitated the dissipation of thiencarbazone-methyl·isoxaflutole residues and further improved the diversity of soil microflora. In addition, the presence of modified attapulgite was found to increase the soil pH, which may improve bacterial diversity through the regulating pathway. This explained the high ecological benefits of the treatment where the thiencarbazone-methyl·isoxaflutole was applied at the recommended dosage rates in conjunction with modified attapulgite addition. Therefore, the comprehensive benefits of thiencarbazone-methyl·isoxaflutole application with a focus on ecological benefits can be improved by regulating the soil pH with modified attapulgite.


Assuntos
Herbicidas , Isoxazóis , Compostos de Magnésio , Compostos de Silício , Herbicidas/química , Solo , Bactérias/metabolismo , Microbiologia do Solo
4.
J Hazard Mater ; 463: 132890, 2024 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-37922582

RESUMO

Large areas of crop yields in northern China have faced with cadmium (Cd) contamination problems. Mercapto-modified palygorskite (MP), as a highly efficient immobilization material, could reduce Cd absorption in wheat and alleviate its biotoxicity. However, the molecular mechanism underlying MP-mediated Cd reduction and detoxification processes in wheat is not well understood. This aim of this study was to investigate the biochemical and molecular mechanisms underlying the reduction in Cd accumulation in wheat (Triticum aestivum L.). The results showed that MP application decreased the Cd concentration by 68.91-74.32% (root) and 70.68-77.2% (shoot), and significantly increased the glutathione (GSH) and phytochelatins (PCs) contents in root and shoot. In addition, with the application of MP, the percentage of Cd in the cell walls and organelles of wheat decreased, while that of Cd in soluble components was increased. The content of Cd in all components was significantly reduced. Ultrastructural analysis revealed that MP thickened the cell wall, promoted vesicle formation in the membrane and protected the integrity of intracellular organelles in wheat. Transcriptome analysis further confirmed the above results. MP upregulated the expression of several genes (CCR, CAD COMT and SUS) involved in cell wall component biosynthesis and promoted vesicle formation on cell membranes by upregulating the expression of PLC and IPMK genes. In addition, genes related to antioxidant synthesis (PGD, glnA and GSS) and photosynthesis (Lhca, Lhcb) were altered by MP to alleviate Cd toxicity in wheat. This present work will help to more thoroughly elucidate the molecular mechanism by which wheat defends against Cd contamination under MP application and provide and important research basis for the application of this material in the future.


Assuntos
Cádmio , Poluentes do Solo , Cádmio/metabolismo , Triticum/genética , Triticum/metabolismo , Transcriptoma , Compostos de Silício , Glutationa/metabolismo , Poluentes do Solo/metabolismo
5.
Artigo em Inglês | MEDLINE | ID: mdl-38083739

RESUMO

A lab-on-a-chip multichannel sensing platform for biomedical analysis based on optical silicon nitride (SiNx) microring-resonators (MRR) was established. The resonators were surface functionalized and finally combined with a microfluidic chamber for validation using an avidin-biotin ligand-binding assay. The results with a limit of detection (LOD) of 2.3∙10-5 and a mean intra-assay coefficient of variation (CV) of ±10.0 %, also under consideration of FDA guidelines, show promising future applicability for a wide variety of targets in the field of outpatient medical diagnostics and life science.Clinical Relevance- Biomarkers play a crucial role in physiological processes of the human body. To enable instantaneous and decentralized analysis of these markers, systems are needed that can be used in a laboratory-independent environment with minimal amounts of biofluid. An example is the utilization of such systems for neonates or infants.


Assuntos
Técnicas Biossensoriais , Óptica e Fotônica , Recém-Nascido , Humanos , Técnicas Biossensoriais/métodos , Fótons , Compostos de Silício
6.
Int J Mol Sci ; 24(16)2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37628838

RESUMO

Hydrolytic reactions taking place at the surface of a silicon nitride (Si3N4) bioceramic were found to induce instantaneous inactivation of Human herpesvirus 1 (HHV-1, also known as Herpes simplex virus 1 or HSV-1). Si3N4 is a non-oxide ceramic compound with strong antibacterial and antiviral properties that has been proven safe for human cells. HSV-1 is a double-stranded DNA virus that infects a variety of host tissues through a lytic and latent cycle. Real-time reverse transcription (RT)-polymerase chain reaction (PCR) tests of HSV-1 DNA after instantaneous contact with Si3N4 showed that ammonia and its nitrogen radical byproducts, produced upon Si3N4 hydrolysis, directly reacted with viral proteins and fragmented the virus DNA, irreversibly damaging its structure. A comparison carried out upon testing HSV-1 against ZrO2 particles under identical experimental conditions showed a significantly weaker (but not null) antiviral effect, which was attributed to oxygen radical influence. The results of this study extend the effectiveness of Si3N4's antiviral properties beyond their previously proven efficacy against a large variety of single-stranded enveloped and non-enveloped RNA viruses. Possible applications include the development of antiviral creams or gels and oral rinses to exploit an extremely efficient, localized, and instantaneous viral reduction by means of a safe and more effective alternative to conventional antiviral creams. Upon incorporating a minor fraction of micrometric Si3N4 particles into polymeric matrices, antiherpetic devices could be fabricated, which would effectively impede viral reactivation and enable high local effectiveness for extended periods of time.


Assuntos
Herpesvirus Humano 1 , Humanos , Compostos de Silício/farmacologia , Antivirais/farmacologia , DNA Viral
7.
Biomater Adv ; 153: 213569, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37531822

RESUMO

This study reported the development of a composite sponge (ACATS) based on alkylated chitosan (AC) and attapulgite (AT) for rapid hemostasis. The well-designed ACATS, with an optimal AC N-alkylation of 5.9 % and an optimal AC/AT mass ratio of 3:1, exhibited a hierarchical porous structure with a favorable biocompatibility. The ACATS can effectively and rapidly stop the uncontrolled bleeding in 235 ± 64 s with a total blood loss of 8.4 ± 4.0 g in comparison with those of Celox as a positive control (602 ± 101 s and 22.3 ± 2.4 g, respectively) using rabbit carotid artery injury model in vivo. ACATS could rapidly interact with blood and its components, including platelets (PLs), red blood cells (RBCs), and coagulation factors, resulting in these blood components rapidly accumulation and the following thrombus formation and coagulation factors activation.


Assuntos
Quitosana , Hemostáticos , Animais , Coelhos , Quitosana/química , Quitosana/farmacologia , Hemostáticos/uso terapêutico , Hemostáticos/química , Hemostáticos/farmacologia , Hemostasia , Compostos de Silício/farmacologia
8.
J Chem Phys ; 159(1)2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37417756

RESUMO

Using a combination of tight binding molecular dynamics and ab initio molecular dynamics simulations, we study the mechanisms of bombardment-induced decomposition of hydrofluorocarbons (HFCs) physisorbed on silicon nitride for ion energies of ≤35 eV. We propose three key mechanisms by which bombardment-driven HFC decomposition can occur, focusing on the two pathways observed at these low ion energies: "direct decomposition" and "collision assisted surface reactions (CASRs)." Our simulation results clearly demonstrate the importance of the presence of favorable reaction coordinates for enabling CASR, which dominates at lower energies (≈11 eV). At higher energies, direct decomposition becomes more favored. Our work also predicts that the primary decomposition pathways for CH3F and CF4 are CH3F → CH3 + F and CF4 → CF2 + 2F, respectively. The fundamental details of these decomposition pathways and the decomposition products formed under ion bombardment have implications for plasma-enhanced atomic layer etching process design that will be discussed.


Assuntos
Simulação de Dinâmica Molecular , Compostos de Silício , Argônio
9.
Opt Lett ; 48(13): 3367-3370, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37390132

RESUMO

Lithium niobate-on-insulator (LNOI) is a promising integration platform for various applications, such as optical communication, microwave photonics, and nonlinear optics. To make Lithium niobate (LN) photonic integrated circuits (PICs) more practical, low-loss fiber-chip coupling is essential. In this Letter, we propose and experimentally demonstrate a silicon nitride (SiN) assisted tri-layer edge coupler on LNOI platform. The edge coupler consists of a bilayer LN taper and an interlayer coupling structure composed of an 80 nm-thick SiN waveguide and an LN strip waveguide. The measured fiber-chip coupling loss for the TE mode is 0.75 dB/facet at 1550 nm. Transition loss between the SiN waveguide and LN strip waveguide is ∼0.15 dB. In addition, the fabrication tolerance of the SiN waveguide in the tri-layer edge coupler is high.


Assuntos
Óxidos , Fótons , Compostos de Silício
10.
Molecules ; 28(11)2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37298792

RESUMO

This review describes the role of silicon (Si) in plants. Methods of silicon determination and speciation are also reported. The mechanisms of Si uptake by plants, silicon fractions in the soil, and the participation of flora and fauna in the Si cycle in terrestrial ecosystems have been overviewed. Plants of Fabaceae (especially Pisum sativum L. and Medicago sativa L.) and Poaceae (particularly Triticum aestivum L.) families with different Si accumulation capabilities were taken into consideration to describe the role of Si in the alleviation of the negative effects of biotic and abiotic stresses. The article focuses on sample preparation, which includes extraction methods and analytical techniques. The methods of isolation and the characterization of the Si-based biologically active compounds from plants have been overviewed. The antimicrobial properties and cytotoxic effects of known bioactive compounds obtained from pea, alfalfa, and wheat were also described.


Assuntos
Compostos de Silício , Silício , Humanos , Silício/farmacologia , Triticum , Medicago sativa , Ecossistema
11.
J Agric Food Chem ; 71(47): 18188-18196, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-37191337

RESUMO

Silicon-containing compounds are sporadically used in crop protection and drug discovery and have demonstrated to increase the biological efficacy as well as to reduce toxicity, improve physicochemical properties, and favorably impact the environmental profile. As part of our research, we have investigated the application of bioisosteric silicon replacements in meta-diamide insecticides and studied the biological activity and molecular properties of the corresponding novel compounds. At all meaningful structural elements of the meta-diamides, silicon-containing substituents were introduced and synthetic methodology was developed for their syntheses. As the most promising compound, silicon-containing meta-diamide II-18 emerged, which exhibits a very low LC50 value of 2.00 mg/L against Mythimna separata and compares well to the reference compounds 28 (LC50 = 0.17 mg/L) and II-20 (LC50 = 0.27 mg/L). Our research on silicon-containing crop protection compounds once again confirmed that the biological activity can be beneficially affected by the insertion of silicone substituents and that the introduction of well-chosen silicone motifs is an excellent strategy for agrochemical research.


Assuntos
Inseticidas , Mariposas , Animais , Inseticidas/química , Relação Estrutura-Atividade , Diamida/química , Silício/farmacologia , Compostos de Silício , Silicones
12.
J Mech Behav Biomed Mater ; 141: 105756, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36898355

RESUMO

For decades, titanium has been the preferred material for dental implant fabrication. However, metallic ions and particles can cause hypersensitivity and aseptic loosening. The growing demand for metal-free dental restorations has also promoted the development of ceramic-based dental implants, such as silicon nitride. In this study, silicon nitride (Si3N4) dental implants were fabricated for biological engineering by photosensitive resin based digital light processing (DLP) technology, comparable to conventionally produced Si3N4 ceramics. The flexural strength was (770 ± 35) MPa by the three-point bending method, and the fracture toughness was (13.3 ± 1.1) MPa · m1/2 by the unilateral pre-cracked beam method. The elastic modulus measured by the bending method was (236 ± 10) GPa. To confirm whether the prepared Si3N4 ceramics possessed good biocompatibility, in vitro biological experiments were performed with the fibroblast cell line L-929, and preferable cell proliferation and apoptosis were observed at the initial stages. Hemolysis test, oral mucous membrane irritation test, and acute systemic toxicity test (oral route) further confirmed that the Si3N4 ceramics did not exhibit hemolysis reaction, oral mucosal stimulation, or systemic toxicity. The findings indicate that Si3N4 dental implant restorations with personalized structures prepared by DLP technology have good mechanical properties and biocompatibility, which has great application potential in the future.


Assuntos
Materiais Biocompatíveis , Implantes Dentários , Humanos , Materiais Biocompatíveis/farmacologia , Teste de Materiais , Hemólise , Compostos de Silício , Cerâmica/química , Tecnologia , Propriedades de Superfície
13.
ACS Sens ; 8(2): 739-747, 2023 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-36787432

RESUMO

Wearable, mobile, and point-of-care (POC) sensors comprise a rapidly expanding field of devices aimed at improving human health by relaying real-time biometric data such as heart rate and glucose levels. The current scope of what these devices can offer healthcare is limited by their inability to measure biomarkers associated with inflammation, well-being, and disease. Photonic biosensors that integrate sensing elements directly with spectrometers, lasers, and detectors are an attractive approach to enabling POC sensors, with distinct advantages in terms of size, weight, power consumption, and cost. Here, we have demonstrated for the first time the integration of photonic microring resonator biosensors with an on-chip microring filter bank spectrometer for the controlled detection of inflammatory biomarker C-reactive protein (CRP) in serum. We demonstrate that sensor and spectrometer performance is tolerant of temperature variation, as temperature dependence moves in parallel. Finally, we assess the impact of manufacturing variability on the 300 mm wafer scale on the performance of the spectrometer. Taken together, these results suggest that integration of on-chip ring filter bank spectrometers with ring resonator-based biosensors constitutes an attractive approach toward cost-effective integrated sensor development.


Assuntos
Óptica e Fotônica , Refratometria , Humanos , Compostos de Silício , Fótons , Biomarcadores
14.
Adv Mater ; 35(16): e2210342, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36823450

RESUMO

The single-molecule technique for investigation of an unlabeled protein in solution is very attractive but with great challenges. Nanopore sensing as a label-free tool can be used for collecting the structural information of individual proteins, but currently offers only limited capabilities due to the fast translocation of the target. Here, a reliable and facile method is developed to convert the silicon nitride nanopore to a stable nanonet platform for single-entity sensing by electrophoretic or electroosmotic trapping. A nanonet is fabricated based on a material reorganization process caused by electron-beam and light-irradiation treatment. Using protein molecules as a model, it is revealed that the solid-state nanonet can produce collision and trapping flipping signals of the protein, which provides more structural information than traditional nanopore sensing. More importantly, thanks to the excellent stability of the solid-state silicon nitride nanonet, it is demonstrated that the ultraviolet-light-irradiation-induced structural-change process of an individual protein can be captured. The developed nanonet supplies a robust platform for single-entity studies but is not limited to proteins.


Assuntos
Nanoporos , Compostos de Silício/química , Nanotecnologia
15.
J Biomed Mater Res A ; 111(3): 309-321, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36349977

RESUMO

The article deals with the plasma-assisted chemical vapor deposition of 0.3-1.4 µm thick a-C:H:SiOx films in a mixture of argon and polyphenylmethylsiloxane vapor onto the Ti-6Al-4V alloy substrate, which is often used as an implant material. The a-C:H:SiOx film structure is studied by the Fourier-transform infrared and Raman spectroscopies. The pull-off adhesion test assesses the adhesive strength of a-C:H:SiOx films, and the ball-on-disk method is employed to measure their wear rate and friction coefficient. According to these studies, a-C:H:SiOx films are highly adhesive to the Ti-6Al-4V substrate, have low (0.056) friction coefficient and wear rate (9.8 × 10-8  mm3  N-1  m-1 ) in phosphate-buffered saline at 40°C. In vitro studies show neither thrombogenicity nor cytotoxicity of the a-C:H:SiOx film for the human blood mononuclear cells (hBMNCs). The in vitro contact between the hBMNC culture and a-C:H:SiOx films 0.8-1.4 µm thick deposited onto Ti-6Al-4V substrates reduces a 24-hour secretion of pro-inflammatory cytokines and chemokines IL-8, IL-17, TNFα, RANTES, and MCP-1. This reduction is more significant when the film thickness is 1.4 µm and implies its potential anti-inflammatory effect and possible application in cardiovascular surgery. The dependence is suggested for the concentration of anti-inflammatory cytokines and chemokines and the a-C:H:SiOx film thickness, which correlates with the surface wettability and electrostatic potential. The article discusses the possible applications of the anti-inflammatory effect and low thrombogenicity of a-C:H:SiOx films in cardiovascular surgery.


Assuntos
Ligas , Titânio , Humanos , Ligas/farmacologia , Ligas/química , Citocinas , Dureza , Leucócitos , Titânio/farmacologia , Titânio/química , Compostos de Silício/química
16.
Biosensors (Basel) ; 12(12)2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36551105

RESUMO

Microfluidic liquid cells have been developed to visualize nanoscaled biological samples in liquid using a scanning electron microscope (SEM) through an electron-transparent membrane (ETM). However, despite the combination of the high-resolution visualization of SEM and the high experimental capability of microfluidics, the image is unclear because of the scattering of the electron beam in the ETM. Thus, this study developed a microfluidic liquid cell with a super-thin ETM of thickness 10 nm. Because the super-thin ETM is excessively fragile, the bonding of a silicon-nitride-deposited substrate and a polydimethylsiloxane microchannel before silicon anisotropic etching was proposed prevented the super-thin ETM from damage and breakage due to etching. With this protection against etchant using the microchannel, the yield of the fabricated super-thin ETM increased from 0 to 87%. Further, the scattering of the electron beam was suppressed using a microfluidic liquid cell with a super-thin ETM, resulting in high-resolution visualization. In addition, T4 bacteriophages were visualized using a super-thin ETM in vacuum. Furthermore, the cyanobacterium Synechocystis sp. PCC6803 in liquid was visualized using a super-thin ETM, and sub-microscopic structures on the surface were observed.


Assuntos
Microfluídica , Compostos de Silício , Microfluídica/métodos , Microscopia Eletrônica , Compostos de Silício/química , Bactérias
17.
Small ; 18(52): e2205667, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36373682

RESUMO

Aqueous zinc-ion batteries (AZIBs) have drawn the attention of numerous researchers owing to their high safety and cost-effectiveness. However, the dendrite growth and side reactions of the zinc (Zn) anodes limit their further practical applications. Herein, a porous amorphous silicon nitride protective layer with high zincophobicity is constructed on the Zn anode surface, which can guide the uniform stripping/plating of Zn2+ underneath the protective layer through its isotropic Zn affinity to alleviate the growth of dendrites and by-products. As a result, the amorphous silicon nitride-protected Zn anode can maintain a stable Coulombic efficiency (CE) of 98.8% and low voltage hysteresis for 710 cycles in the half cell. The full cell with the as-prepared Zn anode can deliver excellent electrochemical performances (89.0% capacity retention and 144.4 mAh g-1 discharge capacity after 1000 cycles at 4 A g-1 ). This work reveals the key role of uniform metal affinity induced by the amorphous materials in the interface modification of metal anodes, which is instructive for the design of stable metal anodes.


Assuntos
Líquidos Corporais , Zinco , Compostos de Silício , Eletrodos
18.
Molecules ; 27(19)2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36234929

RESUMO

The biodegradation of wood and wood products caused by fungi is recognized as one of the most significant problems worldwide. To extend the service life of wood products, wood is treated with preservatives, often with inorganic compounds or synthetic pesticides that have a negative impact on the environment. Therefore, the development of new, environmentally friendly wood preservatives is being carried out in research centers around the world. The search for natural, plant, or animal derivatives as well as obtaining synthetic compounds that will be safe for humans and do not pollute the environment, while at the same time present biological activity is crucial in terms of environmental protection. The review paper presents information in the literature on the substances and chemical compounds of natural origin (plant and animal derivatives) and synthetic compounds with a low environmental impact, showing antifungal properties, used in research on the ecological protection of wood. The review includes literature reports on the potential application of various antifungal agents including plant extracts, alkaloids, essential oils and their components, propolis extract, chitosan, ionic liquids, silicon compounds, and nanoparticles as well as their combinations.


Assuntos
Quitosana , Líquidos Iônicos , Óleos Voláteis , Praguicidas , Própole , Animais , Antifúngicos/química , Antifúngicos/farmacologia , Humanos , Extratos Vegetais/química , Compostos de Silício , Madeira/microbiologia
19.
ACS Nano ; 16(11): 18648-18657, 2022 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36251751

RESUMO

We demonstrate DNA translocations through silicon nitride pores formed by simple chemical etching on glass substrates using microscopic amounts of hydrofluoric acid. DNA translocations and transmission electron microscopy (TEM) prove the fabrication of nanopores and allow their characterization. From ionic measurements on 318 chips, we report the effective pore diameters ranging from zero (pristine membranes) and sub-nm to over 100 nm, within 50 µm diameter membranes. The combination of ionic conductance, DNA current blockades, TEM imaging, and electron energy loss spectroscopy (EELS) provides comprehensive information about the pore area and number, from single to few pores, and pore structure. We also show the formation of thinned membrane regions as precursors of pores. The average pore density, about 5 × 10-4 pores/µm2, allows pore number adjustment statistically (0, 1, or more). This simple and affordable chemical method for making solid-state nanopores accelerates their adoption for DNA sensing and characterization applications.


Assuntos
Nanoporos , Compostos de Silício/química , DNA/química , Microscopia Eletrônica de Transmissão , Íons
20.
Artigo em Inglês | MEDLINE | ID: mdl-36078522

RESUMO

In this study, Mn/Zn@palygorskite (PG) catalysts with developed pores and good salt tolerance were prepared and applied to the treatment of coal chemical wastewater. A doping ratio of metal elements, calcination temperature, and calcination time was used to optimize the preparation conditions and determine the optimal preparation conditions of the Mn/Zn@PG catalysts. The catalysts, obtained under various preparation conditions, were characterized and analyzed by XRD, SEM, EDS, BET, XRF, XPS, and other techniques. Results showed that the Zn and Mn elements in the Mn/Zn@PG catalyst existed as ZnO and MnO2, respectively. The optimal working conditions of the Mn/Zn@PG catalyst for catalytic oxidation treatment of coal chemical wastewater, obtained through the optimization of working conditions, are the following: reaction time 60 min, wastewater pH = 9.28, ozone ventilation rate 0.2 L/min, catalyst filling ratio 20%. The height-to-diameter ratio of the tower was 6:1. The abrasion resistance and catalytic performance of the Mn/Zn@PG catalyst after repeated use were investigated, and the mechanism of the loss of active components of the Mn/Zn@PG catalyst was explored. The coal chemical wastewater, before and after treatment, was analyzed by UV-vis spectroscopy and 3D fluorescence spectroscopy. The hierarchical-principal component comprehensive evaluation system (AHP-PCA) was established to evaluate the catalytic ozonation process of coal chemical wastewater, so that the overall evaluation of the process performance can be achieved.


Assuntos
Ozônio , Águas Residuárias , Catálise , Carvão Mineral , Compostos de Magnésio , Compostos de Manganês , Óxidos , Ozônio/química , Compostos de Silício , Águas Residuárias/química , Zinco
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