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1.
Curr Probl Cardiol ; 49(9): 102746, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-39002618

RESUMO

Nutrition can play a key role in cardiovascular disease risk reduction, and its risk factors modification. This paper aims to present, compare, and summarize the main dietary concepts for preventing the main cardiovascular disease risk factors - obesity, hypertension, and dyslipidemia. The dietary models and macronutrient intakes were compared between main cardiovascular risk factors prevention recommendations. Dietary recommendations related to selected cardiovascular risk factors share the points, that can be suggested as crucial for overall cardiovascular risk factors reduction. Recommendations suggest limiting saturated fatty acids intake to <10% of total caloric intake in obesity, and <7 % in hypercholesterolemia, along with an increased intake of mono- and polyunsaturated fatty acids. In addition, daily dietary fiber intake should reach a level of 25-40 g. The vegetables and fruits should be consumed at a daily minimum level of 200g (or 4-5 portions) each. Salt intake should not exceed 5g/day. Alcohol should be generally avoided, and moderate intake levels (sex-specific) should not be exceeded. It is also worth noting, that proteins are essential for tissue formation and regeneration. Carbohydrates are the main source of energy, but it is necessary to choose products with a low glycemic index. Dietary antioxidants help combat free radicals and prevent cell damage.

2.
Sensors (Basel) ; 24(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38732878

RESUMO

The article reviews issues associated with the operation of stationary and non-stationary electronic fire alarm systems (FASs). These systems are employed for the fire protection of selected buildings (stationary) or to monitor vast areas, e.g., forests, airports, logistics hubs, etc. (non-stationary). An FAS is operated under various environmental conditions, indoor and outdoor, favourable or unfavourable to the operation process. Therefore, an FAS has to exhibit a reliable structure in terms of power supply and operation. To this end, the paper discusses a representative FAS monitoring a facility and presents basic tactical and technical assumptions for a non-stationary system. The authors reviewed fire detection methods in terms of fire characteristic values (FCVs) impacting detector sensors. Another part of the article focuses on false alarm causes. Assumptions behind the use of unmanned aerial vehicles (UAVs) with visible-range cameras (e.g., Aviotec) and thermal imaging were presented for non-stationary FASs. The FAS operation process model was defined and a computer simulation related to its operation was conducted. Analysing the FAS operation process in the form of models and graphs, and the conducted computer simulation enabled conclusions to be drawn. They may be applied for the design, ongoing maintenance and operation of an FAS. As part of the paper, the authors conducted a reliability analysis of a selected FAS based on the original performance tests of an actual system in operation. They formulated basic technical and tactical requirements applicable to stationary and mobile FASs detecting the so-called vast fires.

3.
J Mater Chem A Mater ; 12(2): 802-812, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38178865

RESUMO

Zeolites have been well known for decades as catalytic materials and adsorbents and are traditionally prepared using the bottom-up synthesis method. Although it was productive for more than 250 zeolite frameworks, the conventional solvothermal synthesis approach provided limited control over the structural characteristics of the formed materials. In turn, the discovery and development of the Assembly-Disassembly-Organization-Reassembly (ADOR) strategy for the regioselective manipulation of germanosilicates enabled the synthesis of previously unattainable zeolites with predefined structures. To date, the family tree of ADOR materials has included the topological branches of UTL, UOV, IWW, *CTH, and IWV zeolites. Herein, we report on the expansion of ADOR zeolites with a new branch related to the IWR topology, which is yet unattainable experimentally but theoretically predicted as highly promising adsorbents for CO2 separation applications. The optimization of not only the chemical composition but also the dimensions of the crystalline domain in the parent IWR zeolite in the Assembly step was found to be the key to the success of its ADOR transformation into previously unknown IPC-17 zeolite with an intersecting 12 × 8 × 8-ring pore system. The structure of the as-prepared IPC-17 zeolite was verified by a combination of microscopic and diffraction techniques, while the results on the epichlorohydrin ring-opening with alcohols of variable sizes proved the molecular sieving ability of IPC-17 with potential application in heterogeneous catalysis. The proposed synthesis strategy may facilitate the discovery of zeolite materials that are difficult or yet impossible to achieve using a traditional bottom-up synthesis approach.

4.
Small ; 20(13): e2309251, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37948352

RESUMO

Conversion of CO2 into value-added products by electrocatalysis provides a promising way to mitigate energy and environmental problems. However, it is greatly limited by the scaling relationship between the adsorption strength of intermediates. Herein, Mn and Ni single-atom catalysts, homonuclear dual-atom catalysts (DACs), and heteronuclear DACs are synthesized. Aberration-corrected annular dark-field scanning transmission electron microscopy (ADF-STEM) and X-ray absorption spectroscopy characterization uncovered the existence of the Mn─Ni pair in Mn─Ni DAC. X-ray photoelectron spectroscopy and X-ray absorption near-edge spectroscopy reveal that Mn donated electrons to Ni atoms in Mn─Ni DAC. Consequently, Mn─Ni DAC displays the highest CO Faradaic efficiency of 98.7% at -0.7 V versus reversible hydrogen electrode (vs RHE) with CO partial current density of 16.8 mA cm-2. Density functional theory calculations disclose that the scaling relationship between the binding strength of intermediates is broken, resulting in superior performance for ECR to CO over Mn─Ni─NC catalyst.

5.
Adv Mater ; 36(4): e2307341, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37800413

RESUMO

Zeolites are highly efficient industrial catalysts and sorbents with microporous framework structures. Approximately 10% of the frameworks, but eventually all in the long run, have produced both 3D crystals and 2D layers. The latter can be intercalated and expanded like all 2D materials but proved difficult to exfoliate directly into suspensions of monolayers in solution as precursors for unique synthetic opportunities. Successful exfoliations have been reported recently and are overviewed in this perspective article. The discussion highlights 3 primary challenges in this field, namely finding suitable 2D zeolite preparations that exfoliate directly in high yield, proving uniform layer thickness in solution and identifying applications to exploit the unique synthetic capabilities and properties of exfoliated zeolite monolayers. Four zeolites have been confirmed to exfoliate directly into monolayers: 3 with known structures-MWW, MFI, and RWR and one unknown, bifer with a unit cell close to ferrierite. The exfoliation into monolayers is confirmed by the combination of 5-6 characterization techniques including AFM, in situ and in-plane XRD, and microscopies. The promising areas of development are oriented films and membranes, intimately mixed zeolite phases, and hierarchical nanoscale composites with other active species like nanoparticles and clusters that are unfeasible by solid state processes.

6.
Dalton Trans ; 52(46): 17279-17288, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-37937421

RESUMO

Palladium nanoparticles find extensive applications in catalysis in both homogeneously and heterogeneously catalyzed processes. Supporting metal nanoparticles enhances their stability as compared to their unsupported counterparts. The role of catalytic support is increasingly recognized as crucial in determining the behaviour of these materials. However, controlling the deposition and anchoring of palladium nanoparticles remains a significant challenge. This contribution discusses the preparation of straight lines of palladium particles on zinc oxide by wet impregnation. This phenomenon is attributed to the highly stepped morphology of the employed ZnO that created steric anchoring sites to stabilize the metal particles. Palladium-based catalysts were evaluated for the valuable Suzuki-Miyaura cross-coupling reaction. The dispersed Pd/ZnO catalyst achieved a conversion rate of 86% with 100% selectivity, remarkably superior to that of the Pd/Al2O3 and Pd/TiO2 counterparts.

7.
Materials (Basel) ; 16(14)2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37512279

RESUMO

Various properties of HfO2, such as hardness, corrosion, or electrical resistance, depend on the method and the conditions of deposition. In this work, a thorough comparison of scarcely investigated mechanical properties of HfO2 thin films deposited with different conditions of reactive magnetron sputtering process is presented. Four thin films were sputtered in processes that varied in plasma ignition method (continuous or sequential) and target-substrate distance. The structural characteristics of the HfO2 thin films were examined using Raman spectroscopy and X-ray diffraction measurements. Furthermore, the optoelectronic properties were determined based on transmittance and current-voltage characteristics. The mechanical properties of the HfO2 thin films were determined using nanoindentation and scratch test. In turn, the corrosion properties were determined by analyzing the voltametric curves. The transparent HfO2 thin films deposited in the continuous process are characterized by better corrosion resistance than the same layer formed in the sequential process, regardless of the target-substrate distance (8 cm or 12 cm). Furthermore, these samples are also characterized by the highest value of Young's modulus and scratch resistance. The combination of good corrosion and scratch resistance could contribute to the new application of HfO2 as a corrosion protective material.

8.
Appl Opt ; 62(7): B156-B163, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37132901

RESUMO

In this paper, the dispersion of a complex refractive index is investigated and proposed as a way to analyze the change of the optical properties of gasochromic material under the influence of diluted hydrogen (3.5% H 2 in Ar) as an active volatile medium. Therefore, a tungsten trioxide thin film and an additional platinum catalyst were deposited by electron beam evaporation and used as a prototype material. Based on experimental verification, it is shown that the proposed method allows one to explain the reasons for the observed changes in the transparency in such materials.

9.
Materials (Basel) ; 16(10)2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37241458

RESUMO

Hydrogen gas sensors have recently attracted increased interest due to the explosive nature of H2 and its strategic importance in the sustainable global energy system. In this paper, the tungsten oxide thin films deposited by innovative gas impulse magnetron sputtering have been investigated in terms of their response to H2. It was found that the most favourable annealing temperature in terms of sensor response value, as well as response and recovery times, was achieved at 673 K. This annealing process caused a change in the WO3 cross-section morphology from a featureless and homogenous form to a rather columnar one, but still maintaining the same surface homogeneity. In addition to that, the full-phase transition from an amorphous to nanocrystalline form occurred with a crystallite size of 23 nm. It was found that the sensor response to only 25 ppm of H2 was equal to 6.3, which is one of the best results presented in the literature so far of WO3 optical gas sensors based on a gasochromic effect. Moreover, the results of the gasochromic effect were correlated with the changes in the extinction coefficient and the concentration of the free charge carriers, which is also a novel approach to the understanding of the gasochromic phenomenon.

10.
J Am Chem Soc ; 145(16): 9081-9091, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37040083

RESUMO

Zeolites are key materials in both basic research and industrial applications. However, their synthesis is neither diverse nor applicable to labile frameworks because classical procedures require harsh hydrothermal conditions, whereas post-synthesis methods are limited to a few suitable parent materials. Remaining frameworks can fail due to amorphization, dissolution, and other decomposition processes. Nevertheless, stopping degradation at intermediate structures could yield new zeolites. Here, by optimizing the design and synthesis parameters of the parent zeolite IWV, we "caught" a new, highly crystalline, and siliceous zeolite during its degradation. IWV seed-assisted crystallization followed by gentle transformation into the water-alcohol system yielded the highly crystalline daughter zeolite IPC-20, whose structure was solved by precession-assisted three-dimensional electron diffraction. Without additional requirements, as in conventional (direct or post-synthesis) strategies, our approach may be applied to any chemically labile material with a staged structure.

11.
Sensors (Basel) ; 23(8)2023 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-37112164

RESUMO

Hydrogen is an efficient source of clean and environmentally friendly energy. However, because it is explosive at concentrations higher than 4%, safety issues are a great concern. As its applications are extended, the need for the production of reliable monitoring systems is urgent. In this work, mixed copper-titanium oxide ((CuTi)Ox) thin films with various copper concentrations (0-100 at.%), deposited by magnetron sputtering and annealed at 473 K, were investigated as a prospective hydrogen gas sensing material. Scanning electron microscopy was applied to determine the morphology of the thin films. Their structure and chemical composition were investigated by X-ray diffraction and X-ray photoelectron spectroscopy, respectively. The prepared films were nanocrystalline mixtures of metallic copper, cuprous oxide, and titanium anatase in the bulk, whereas at the surface only cupric oxide was found. In comparison to the literature, the (CuTi)Ox thin films already showed a sensor response to hydrogen at a relatively low operating temperature of 473 K without using any extra catalyst. The best sensor response and sensitivity to hydrogen gas were found in the mixed copper-titanium oxides containing similar atomic concentrations of both metals, i.e., 41/59 and 56/44 of Cu/Ti. Most probably, this effect is related to their similar morphology and to the simultaneous presence of Cu and Cu2O crystals in these mixed oxide films. In particular, the studies of surface oxidation state revealed that it was the same for all annealed films and consisted only of CuO. However, in view of their crystalline structure, they consisted of Cu and Cu2O nanocrystals in the thin film volume.

12.
Ultrason Sonochem ; 95: 106377, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36966658

RESUMO

In this study, a sonochemical route for the preparation of a new Hf-MIL-140A metal-organic framework from a mixture of UiO-66/MIL-140A is presented. The sonochemical synthesis route not only allows the phase-pure MIL-140A structure to be obtained but also induces structural defects in the MIL-140A structure. The synergic effect between the sonochemical irradiation and the presence of a highly acidic environment results in the generation of slit-like defects in the crystal structure, which increases specific surface area and pore volume. The BET-specific surface area in the case of sonochemically derived Zr-MIL-140A reaches 653.3 m2/g, which is 1.5 times higher than that obtained during conventional synthesis. The developed Hf-MIL-140A structure is isostructural to Zr-MIL-140A, which was confirmed by synchrotron X-ray powder diffraction (SR-XRD) and by continuous rotation electron diffraction (cRED) analysis. The obtained MOF materials have high thermal and chemical stability, which makes them promising candidates for applications such as gas adsorption, radioactive waste removal, catalysis, and drug delivery.

13.
Angew Chem Int Ed Engl ; 62(1): e202213361, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36342499

RESUMO

Supported metal nanoparticles are used as heterogeneous catalysts but often deactivated due to sintering at high temperatures. Confining metal species into a porous matrix reduces sintering, yet supports rarely provide additional stabilization. Here, we used the silanol-rich layered zeolite IPC-1P to stabilize ultra-small Rh nanoparticles. By adjusting the IPC-1P interlayer space through swelling, we prepared various architectures, including microporous and disordered mesoporous. In situ scanning transmission electron microscopy confirmed that Rh nanoparticles are resistant to sintering at high temperature (750 °C, 6 hrs). Rh clusters strongly bind to surface silanol quadruplets at IPC-1P layers by hydrogen transfer to clusters, while high silanol density hinders their migration based on density functional theory calculations. Ultimately, combining swelling with long-chain surfactant and utilizing metal-silanol interactions resulted in a novel, catalytically active material-Rh@IPC_C22.

14.
Materials (Basel) ; 17(1)2023 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-38203938

RESUMO

This paper presents a detailed analysis of aluminium-doped zinc oxide (AZO) thin films and considers them a promising alternative to indium tin oxide in transparent electrodes. The study focusses on critical properties of AZO, including optical, electrical, and mechanical properties, with potential applications in displays, photovoltaic cells, and protective coatings. The deposited AZO thin films are characterised by excellent optical and electrical parameters, with transparency in the visible light range exceeding 80% and resistivity of 10-3 Ω·cm, which gives a high value of figure of merit of 63. Structural analysis confirms the nanocrystalline nature of as-deposited AZO thin films, featuring hexagonal ZnO, orthorhombic Al2O3, and cubic Al2ZnO4 phases. The study includes nanoindentation measurements, which reveal exceptional hardness (11.4 GPa) and reduced elastic modulus (98 GPa), exceeding typical values reported in the literature, highlighting their protective potential. Abrasion tests have shown extraordinary scratch resistance due to the lack of impact on topography and surface roughness up to 10,000 cycles. This comprehensive study demonstrated that as-deposited AZO thin films are multifunctional materials with exceptional optical, electrical, and mechanical properties. The findings open up possibilities for a variety of applications, especially in protective coatings, where the combination of hardness, scratch resistance, and transparency is both rare and valuable.

15.
Materials (Basel) ; 15(19)2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36233893

RESUMO

The paper presents the results of an investigation of the influence of technological parameters on the microstructure, optical, electrical and nanomechanical properties of zinc oxide coatings prepared using the pulsed reactive magnetron sputtering method. Three sets of ZnOx thin films were deposited in metallic, shallow dielectric and deep dielectric sputtering modes. Structural investigations showed that thin films deposited in the metallic mode were nanocrystalline with mixed hexagonal phases of metallic zinc and zinc oxide with crystallite size of 9.1 and 6.0 nm, respectively. On the contrary, the coatings deposited in both dielectric modes had a nanocrystalline ZnO structure with an average crystallite size smaller than 10 nm. Moreover, coatings deposited in the dielectric modes had an average transmission of 84% in the visible wavelength range, while thin films deposited in the metallic mode were opaque. Measurements of electrical properties revealed that the resistivity of as-deposited thin films was in the range of 10-4 Ωcm to 108 Ωcm. Coatings deposited in the metallic mode had the lowest hardness of 2.2 GPa and the worst scratch resistance among all sputtered coatings, whereas the best mechanical properties were obtained for the film sputtered in the deep dielectric mode. The obtained hardness of 11.5 GPa is one of the highest reported to date in the literature for undoped ZnO.

16.
JACS Au ; 2(10): 2327-2338, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36311841

RESUMO

Confining Au nanoparticles (NPs) in a restricted space (e.g., zeolite micropores) is a promising way of overcoming their inherent thermal instability and susceptibility to aggregation, which limit catalytic applications. However, such approaches involve complex, multistep encapsulation processes. Here, we describe a successful strategy and its guiding principles for confining small (<2 nm) and monodisperse Au NPs within commercially available beta and MFI zeolites, which can oxidize CO at 40 °C and show size-selective catalysis. This protocol involves post-synthetic modification of the zeolite internal surface with thiol groups, which confines AuCl x species inside microporous frameworks during the activation process whereby Au precursors are converted into Au nanoparticles. The resulting beta and MFI zeolites contain uniformly dispersed Au NPs throughout the void space, indicating that the intrinsic stability of the framework promotes resistance to sintering. By contrast, in situ scanning transmission electron microscopy (STEM) studies evidenced that Au precursors in bare zeolites migrate from the matrix to the external surface during activation, thereby forming large and poorly dispersed agglomerates. Furthermore, the resistance of confined Au NPs against sintering is likely relevant to the intrinsic stability of the framework, supported by extended X-ray absorption fine structure (EXAFS), H2 chemisorption, and CO Fourier transform infrared (FT-IR) studies. The Au NPs supported on commercial MFI maintain their uniform dispersity to a large extent after treatment at 700 °C that sinters Au clusters on mesoporous silicas or beta zeolites. Low-temperature CO oxidation and size-selective reactions highlight that most gold NPs are present inside the zeolite matrix with a diameter smaller than 2 nm. These findings illustrate how confinement favors small, uniquely stable, and monodisperse NPs, even for metals such as Au susceptible to cluster growth under conditions often required for catalytic use. Moreover, this strategy may be readily adapted to other zeolite frameworks that can be functionalized by thiol groups.

17.
ChemSusChem ; 15(19): e202200870, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-35929076

RESUMO

Developing highly efficient electrocatalysts for electrochemical CO2 reduction (ECR) to value-added products is important for CO2 conversion and utilization technologies. In this work, a sulfur-doped Ni-N-C catalyst is fabricated through a facile ion-adsorption and pyrolysis treatment. The resulting Ni-NS-C catalyst exhibits higher activity in ECR to CO than S-free Ni-N-C, yielding a current density of 20.5 mA cm-2 under -0.80 V versus a reversible hydrogen electrode (vs. RHE) and a maximum CO faradaic efficiency of nearly 100 %. It also displays excellent stability with negligible activity decay after electrocatalysis for 19 h. A combination of experimental investigations and DFT calculations demonstrates that the high activity and selectivity of ECR to CO is due to a synergistic effect of the S and Ni-NX moieties. This work provides insights for the design and synthesis of nonmetal atom-decorated M-N-C-based ECR electrocatalysts.

18.
Sensors (Basel) ; 22(14)2022 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-35890779

RESUMO

This paper concerns the problem of vibration reduction during milling. For this purpose, it is proposed that the standard supports of the workpiece be replaced with adjustable stiffness supports. This affects the modal parameters of the whole system, i.e., object and its supports, which is essential from the point of view of the relative tool-workpiece vibrations. To reduce the vibration level during milling, it is necessary to appropriately set the support stiffness coefficients, which are obtained from numerous milling process simulations. The simulations utilize the model of the workpiece with adjustable supports in the convention of a Finite Element Model (FEM) and a dynamic model of the milling process. The FEM parameters are tuned based on modal tests of the actual workpiece. For assessing simulation results, the proper indicator of vibration level must be selected, which is also discussed in the paper. However, simulating the milling process is time consuming and the total number of simulations needed to search the entire available range of support stiffness coefficients is large. To overcome this issue, the artificial intelligence salp swarm algorithm is used. Finally, for the best combination of stiffness coefficients, the vibration reduction is obtained and a significant reduction in search time for determining the support settings makes the approach proposed in the paper attractive from the point of view of practical applications.

20.
Beilstein J Nanotechnol ; 13: 344-354, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35425692

RESUMO

Al x Zn y O thin films were obtained by reactive pulsed magnetron sputtering. A two-element Zn/Al planar target was used as source material prepared in the form of a Zn disc (100 mm diameter) with Al rings pressed into its surface. The sputtering processes were carried out in a mixture of argon and oxygen. The films were deposited with a discharge power of P E = 400 W, which corresponded to a power density on the target surface of approximately 5 W/cm2. The films were deposited on glass strip substrates, placed symmetrically over the target, making it possible to obtain films with different composition and thickness. The film sheet resistance was measured as a function of the distance from the target axis on both sides (front and back) of the substrate. The lowest measured resistivity was about 4 × 10-3 Ω·cm. Additionally, optical properties, surface topography, and elemental composition were determined in selected areas of the substrate.

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