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1.
Environ Sci Technol ; 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39390686

RESUMO

Goethite often harbors impurities, such as phosphorus (P) and aluminum (Al), which are incorporated into its structure through direct substitution or coprecipitation with nanocrystalline phases. Understanding the processes that drive the release of P and Al from goethite is of paramount importance for the iron ore industry and for managing nutrient and pollutant behavior in the environment. This study investigates the impact of Fe(II)-catalyzed recrystallization on the release of P and Al from goethite. We evaluated the solubility and extractability of P and Al in suspensions of Al- and P-coprecipitated goethite, treated with 57Fe-enriched Fe(II)aq under oxygen-free conditions for 30 days at neutral pH and room temperatures. The addition of Fe(II)aq induced the recrystallization of goethite dominant initial synthetic phases (i.e., low P- and Al-containing phases) and the transformation of higher P- and/or Al-bearing starting material that was actually a mixture of goethite and minor amounts of lepidocrocite and feroxyhyte. Our results reveal that Fe(II)-catalyzed mineral and structural evolution led to the repartitioning of P and, to a lesser extent, Al throughout the crystal structure, mineral surface, and aqueous solution. Following a 30 day reaction with Fe(II)aq, we extracted approximately 80, 68.8, 73.9, and 83.2% of P from P-only, low, medium, and high P + Al goethite, respectively. Additionally, we observed total Al removals of approximately 17, 27, and 25% from low, medium, and high P + Al goethite, respectively. The results demonstrate that treating both P-only and P + Al goethite with Fe(II) at room temperature, followed by a 24 h extraction using 1 M NaOH, significantly enhances the overall extractability of P and Al, including both aqueous and surface-adsorbed fractions, compared to Fe(II)-free controls. These findings advance our understanding of the recrystallization process and impurity substitution in goethite, offering promising avenues for developing new environmentally friendly methods to extract P and other impurities from goethitic iron ores at lower temperatures.

2.
Sci Rep ; 14(1): 22473, 2024 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-39341899

RESUMO

Basalt-hosted monocentric agates from Bou Hamza (Morocco) were examined to unravel a discrete relationship between moganite content, water content, and the abundance of various types of chalcedony/quartz microtextures, so that the agate-forming process is refined. Herein, moganite content is noticeably low in length-slow chalcedony (quartzine, up to 18 wt.%), as compared with the co-occurring length-fast (LF) chalcedony (up to 31 wt.%). Such a type of disparity reflects a stabilization of the crystallization front during the formation of chalcedonic bands. Recrystallization-related quartz types (i.e. feathery and mosaic/jigsaw puzzle) show low and high moganite content (0 and up to 34 wt.%, respectively) since they have likely originated from different silica precursors (i.e. opaline and chalcedonic, respectively). Meanwhile, the initial formation of mosaic quartz can be exclusively witnessed in the so-called zebraic variety of length-fast chalcedony (i.e. with twisted fibres) that should be hence regarded as a ,,metastable" variety of silica though. The range of total water content remains quite stable across chalcedonic bands (0.5-0.6 wt%) and reaches the highest values (0.7 wt%) in feathery quartz. However, there is rather a general negative relationship between the content of molecular water and silanol-group water. This can stem from the recycling of water species following the condensation reaction of silanols within the agate geodes. The agates originated from Fe-Ti-bearing solutions that co-precipitated goethite, hematite, and rutile, but also contain minor low-grade carbonaceous material.

3.
Eur J Pharm Biopharm ; 203: 114478, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39226986

RESUMO

This method paper describes currently used experimental methods to predict the drug-in-polymer solubility of amorphous solid dispersions and offers a combined approach for applying the Melting-point-depression method, the Recrystallization method, and the Melting-and-mixing method. It aims to describe and expand on the theoretical basis as well as the analytical methodology of the recently published Melting-and-mixing method. This solubility method relies on determining the relationship between drug loads and the enthalpy of melting and mixing of a crystalline drug in the presence of an amorphous polymer. This relationship is used to determine the soluble drug load of an amorphous solid dispersion from the recorded enthalpy of melting and mixing of the crystalline drug portion in a drug-polymer sample at equilibrium solubility. Due to the complex analytical methodology of the Melting-and-mixing method, a software solution called the Glass Solution Companion app was developed. Using this new tool, it is possible to calculate the predicted drug-in-polymer solubility and Flory-Huggins interaction parameter from experimental samples, as well as to generate the resulting solubility-temperature curve. This software can be used for calculations for all three experimental methods, which would be useful for comparing the applicability of the methods on a given drug-polymer system. Since it is difficult to predict the suitability of these drug-in-polymer solubility methods for a specific drug-polymer system in silico, some experimental investigation is necessary. By optimizing the experimental protocol, it is possible to collect data for the three experimental methods simultaneously for a specific drug-polymer system. These results can then be readily analyzed using the Glass Solution Companion app to find the most appropriate method for the drug-polymer system, and therefore, the most reliable drug-in-polymer solubility prediction.


Assuntos
Polímeros , Solubilidade , Polímeros/química , Preparações Farmacêuticas/química , Fluxo de Trabalho , Cristalização , Química Farmacêutica/métodos , Software , Temperatura de Transição
4.
AAPS PharmSciTech ; 25(7): 219, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39299994

RESUMO

The isothermal crystallization process of felodipine has been investigated using the time-domain Nuclear Magnetic Resonance (NMR) method for amorphous bulk and ground samples. The obtained induction and crystallization times were then used to construct the time-temperature-transformation (TTT) diagram, both above and below the glass transition temperature (Tg). The Nose temperature was found equal to 363 K. Furthermore, the dynamics of crystalline and amorphous felodipine were compared across varying temperatures. Molecular dynamics simulations were also employed to explore the hydrogen-bond interactions and dynamic properties of both systems.


Assuntos
Cristalização , Felodipino , Ligação de Hidrogênio , Espectroscopia de Ressonância Magnética , Simulação de Dinâmica Molecular , Temperatura , Felodipino/química , Cristalização/métodos , Espectroscopia de Ressonância Magnética/métodos , Temperatura de Transição
5.
Materials (Basel) ; 17(17)2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39274626

RESUMO

For this article, hot compression tests were carried out on homogenized 2050 Al-Cu-Li alloys under different deformation temperatures and strain rates, and an Arrhenius-type constitutive model with strain compensation was established to accurately describe the alloy flow behavior. Furthermore, thermal processing maps were created and the deformation mechanisms in different working regions were revealed by microstructural characterization. The results showed that most of the deformed grains orientated toward <101>//CD (CD: compression direction) during the hot compression process, and, together with some dynamic recovery (DRV), dynamic recrystallization (DRX) occurred. The appearance of large-scale DRX grains at low temperatures rather than in high-temperature conditions is related to the particle-stimulated nucleation mechanism, due to the dynamic precipitation that occurs during the deformation process. The hot-working diagrams with a true strain of 0.8 indicated that the high strain-rate regions C (300 °C-400 °C, 0.1-1 s-1) and D (440 °C-500 °C, 0.1-1 s-1) are unfavorable for the processing of 2050 Al-Li alloys, owing to the flow instability caused by local deformation banding, microcracks, and micro-voids. The optimum processing region was considered to be 430 °C-500 °C and 0.1 s-1-0.001 s-1, with a dissipation efficiency of more than 30%, dominated by DRV and DRX; the DRX mechanisms are DDRX and CDRX.

6.
Materials (Basel) ; 17(17)2024 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-39274807

RESUMO

The textures of the ß- and α-phases of the metastable ß-titanium alloy Ti5321 after hot deformation were investigated by neutron diffraction. A hot-rolled bar was solutionized in the ß-phase field and then hot compressed above and below the ß-transus temperature. The initial texture after full recrystallization and grain growth in the ß-phase field exhibits a weak cube component {001}<100> and minor {112}<110> and {111}<110> components. After hot compression, a <100> fiber texture is observed, increasing in intensity with compression temperature. Below the ß-transus temperature, dynamic recrystallization of the ß-phase and dynamic spheroidization of the α-phase interact strongly. The texture of the α-phase is a <11-20> fiber texture, increasing in intensity with decreasing compression temperature. The mechanisms of texture formation during hot compression are discussed.

7.
J Agric Food Chem ; 72(39): 21763-21771, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39315455

RESUMO

Effectively controlling ice recrystallization (IR) during the frozen storage of food remains highly challenging. Inspired by the structural characteristics of antifreeze proteins in nature, silk fibroin (SF) derived from silk fibers has been developed. Through dual validation using the "splat" assay and "sucrose sandwich" assay, the IR inhibition activity of SF at various concentrations was confirmed, revealing that its regular alternating hydrophilic/hydrophobic domains endow SF with the potential to inhibit the axial growth of single ice crystal and significantly reduce the average maximum crystal size by approximately 67%. Additionally, the quality stability of frozen muscle foods treated with SF was comprehensively evaluated. In stark contrast to traditional commercial antifreeze agents (4% sucrose and 4% sorbitol), prepared steaks with the addition of 2% SF maintained rich juiciness and excellent color acceptability over a three-month frozen storage period. Thus, SF holds promise as a potential protective agent for frozen muscle foods, enhancing their quality during storage.


Assuntos
Cristalização , Fibroínas , Conservação de Alimentos , Armazenamento de Alimentos , Congelamento , Gelo , Fibroínas/química , Animais , Conservação de Alimentos/métodos , Bombyx/química , Carne/análise , Suínos , Humanos
8.
Heliyon ; 10(18): e37625, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39309870

RESUMO

The present work deals with characterizing the recrystallization accompanied flow and high temperature softening behavior of an extruded AZ61 magnesium alloy. This was supported by conducting a set of hot compression tests at temperatures in the range of 250-450 °C under the strain rate ranging from 0.001 to 0.1s-1. The flow curves at all thermomechanical conditions indicated high fractional softening representing the domination of dynamic recrystallization mechanism. Through a new quantitative approach, "Arrhenius type model", "modified Avrami equations" and Poliak and Jonas method were simultaneously employed to investigate the kinetic of dynamic recrystallization. It was revealed that the strain required for the same amount of recrystallization fraction increased with decreasing deformation temperature, and at a specified temperature, the required strain increases with increasing strain rate. Interestingly, an anomaly was found at 400 °C under the strain rate of 0.001s-1, where the recrystallization kinetic was faster than that of what was recorded at 450 °C. This anomaly was discussed relying on the nanoprecipitation of γ-phase at the prior boundaries and sub-boundaries which prohibited the grain boundary migration and also the rotation and coalescence of adjacent sub-grains.

9.
Materials (Basel) ; 17(16)2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39203119

RESUMO

Magnesium alloys show great promise in high-speed transport, aerospace, and military technology; however, their widespread adoption encounters challenges attributed to limitations such as poor plasticity and strength. This study examines the high-temperature deformation of semi-solid forged AZ91D magnesium alloy through a combination of experiments and simulations, with a focus on comprehending the influence of deformation conditions on dynamic recrystallization (DRX). The findings disclose that conspicuous signs of DRX manifest in the yield stress curve as strain increases. Additionally, decreasing the strain rate and temperature correlates with a reduction in both yield stress and peak strain, and the activation energy is 156.814 kJ/mol, while the critical strain and peak strain remain relatively consistent (εc=0.66208εp). Microstructural changes during high-temperature deformation and the onset of DRX are thoroughly examined through experimental methods. Moreover, a critical strain model for DRX and a predictive model for the volume fraction of DRX were formulated. These equations and models, validated through a combination of experiments and simulations, serve as invaluable tools for predicting the mechanical behavior and microstructural evolution, which also establishes a foundation for accurately predicting the deformation behavior of this alloy. By analyzing the hot deformation characteristics and dynamic compression mechanism of the newly developed semi-solid forging AZ91D magnesium alloy, a numerical simulation model can be effectively established. This model objectively reflects the changes and distributions of stress, strain, and rheological velocity, providing a scientific basis for selecting subsequent plastic deformation process parameters and designing mold structures.

10.
Materials (Basel) ; 17(16)2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39203147

RESUMO

This paper examines the relationship between the magnetization behavior and crystal lattice orientations of Fe-Si alloys intended for magnetic applications. A novel approach is introduced to assess anisotropy of the magnetic losses and first magnetization curves. This method links the magnetocrystalline anisotropy energy of single crystal structures to the textures of polycrystalline materials through a vectorial space description of the crystal unit cell, incorporating vectors for external applied field and saturation magnetization. This study provides a preliminary understanding of how texture influences magnetic loss rates and the first magnetization curves. Experimental results from Electron Back-Scattered Diffraction (EBSD) and Single-Sheet Tests (SSTs), combined with energy considerations and mathematical modeling, reveal the following key findings: (i) a higher density of cubic texture components, whether aligned or rotated relative to the rolling direction, decreases magnetic anisotropy, suggesting that optimizing cubic texture can enhance material performance; (ii) at high magnetic fields, there is no straightforward correlation between energy losses and polarization; and (iii) magnetization rates significantly impact magnetization loss rates, highlighting the importance of considering these rates in optimizing Fe-Si sheet manufacturing processes. These findings offer valuable insights for improving the manufacturing and performance of Fe-Si sheets, emphasizing the need for further exploration of texture effects on magnetic behavior.

11.
Materials (Basel) ; 17(16)2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39203188

RESUMO

Graphene/copper composites are promising in electronic and energy fields due to their superior conductivity, but microstructure control during thermal mechanical processing (TMP) remains a crucial issue for the manufacturing of high-performance graphene/copper composites. In this study, the hot deformation behavior of graphene/copper composites was investigated by isothermal compression tests at deformation temperatures of 700~850 °C and strain rates of 0.01~10 s-1, and a constitutive equation based on the Arrhenius model and hot processing map was established. Results demonstrate that the deformation mechanism of the graphene/copper composites mainly involves dynamic recrystallization (DRX), and such DRX-mediated deformation behavior can be accurately described by the established Arrhenius model. In addition, it was found that the strain rate has a stronger impact on the DRX grain size than the deformation temperature. The optimum deformation temperature and strain rate were determined to be 800 °C and 1 s-1, respectively, with which a uniform microstructure with fine grains can be obtained.

12.
Materials (Basel) ; 17(16)2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39203204

RESUMO

Continuous dynamic recrystallization (CDRX) is widely acknowledged to occur during hot forming and plays a significant role in microstructure development in alloys with moderate to high stacking fault energy. In this work, the flow stress and CDRX behaviors of the TC18 alloy subjected to hot deformation across a wide range of processing conditions are studied. It is observed that deformation leads to the formation of new low-angle grain boundaries (LAGBs). Subgrains rotate by absorbing dislocations, resulting in an increase in LAGB misorientation and the transition of some LAGBs into high-angle grain boundaries (HAGBs). The HAGBs migrate within the material, assimilating the (sub)grain boundaries. Subsequently, an internal state variable (ISV)-based CDRX model is developed, incorporating parameters such as the dislocation density, adiabatic temperature rise, subgrain rotation, LAGB area, HAGB area, and LAGB misorientation angle distribution. The values of the correlation coefficient (R), relative average absolute error (RAAE), and root-mean-square error (RMSE) between the anticipated true stress and measured stress are 0.989, 6.69%, and 4.78 MPa, respectively. The predicted outcomes demonstrate good agreement with experimental findings. The evolving trends of the subgrain boundary area under various conditions are quantitatively analyzed by assessing the changes in dynamic recovery (DRV)-eliminated dislocations and misorientation angles. Moreover, the ISV-based model accurately predicts the decreases in grain and crystallite sizes with higher strain rates and lower temperatures. The projected outcomes also indicate a transition from a stable and coarse-grained microstructure to a continuously recrystallized substructure.

13.
Food Chem ; 460(Pt 2): 140574, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39089028

RESUMO

Creating molecules capable of inhibiting ice recrystallization is an active research area aiming to improve the freeze-thaw characteristics of foods and biomedical materials. Peptide mixtures have shown promise in preventing freezing-induced damage, but less is known about the relationship between their amino acid compositions and ice recrystallization inhibition (IRI) activities. In this article, we used Ni2+ immobilized metal affinity chromatography (IMAC) to fractionate pulse protein hydrolysates, created by Alcalase and trypsin, into mixtures lacking and enriched in His, and Cys residues. The aim of this study was to fractionate pulse protein hydrolysates based on their amino acid compositions and evaluate their resulting physicochemical and IRI characteristics. Ni2+ IMAC fractionation induced IRI activity in all of the evaluated soy, chickpea, and pea protein hydrolysates regardless of their amino acid composition. Ni2+ IMAC fractionation produced chemically distinct fractions of peptides, differing by their molecular weights, amino acid composition, and IRI activities. The resulting peptide mixtures' molecular weight, amino acid composition, secondary structure, and sodium ion levels were found to have no correlation with their IRI activities. Thus, we demonstrate for the first time the ability of Ni2+ IMAC fractionation to induce IRI activity in hydrolyzed pulse proteins.


Assuntos
Cromatografia de Afinidade , Cristalização , Gelo , Níquel , Hidrolisados de Proteína , Hidrolisados de Proteína/química , Níquel/química , Pisum sativum/química , Proteínas de Plantas/química , Cicer/química , Peptídeos/química , Tripsina/química , Peso Molecular , Aminoácidos/química
14.
ACS Nano ; 18(33): 22034-22044, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39106126

RESUMO

Ever since the ground-breaking isolation of graphene, numerous two-dimensional (2D) materials have emerged with 2D metal dihalides gaining significant attention due to their intriguing electrical and magnetic properties. In this study, we introduce an innovative approach via anhydrous solvent-induced recrystallization of bulk powders to obtain crystals of metal dihalides (MX2, with M = Cu, Ni, Co and X = Br, Cl, I), which can be exfoliated to 2D flakes. We demonstrate the effectiveness of our method using CuBr2 as an example, which forms large layered crystals. We investigate the structural properties of both the bulk and 2D CuBr2 using X-ray diffraction, along with Raman scattering and optical spectroscopy, revealing its quasi-1D chain structure, which translates to distinct emission and scattering characteristics. Furthermore, microultraviolet photoemission spectroscopy and electronic transport reveal the electronic properties of CuBr2 flakes, including their valence band structure. We extend our methodology to other metal halides and assess the stability of the metal halide flakes in controlled environments. We show that optical contrast can be used to characterize the flake thicknesses for these materials. Our findings demonstrate the versatility and potential applications of the proposed methodology for preparing and studying 2D metal halide flakes.

15.
Materials (Basel) ; 17(15)2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39124499

RESUMO

To investigate the influence of Zn-alloying on the microstructure and tensile mechanical properties of Mg-6Bi alloy after hot extrusion, a new ternary Mg-6Bi-3Zn alloy was prepared by extrusion at 300 °C. The microstructures, texture, dynamic precipitates and tensile mechanical behaviors of the extruded alloy were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), electron backscattered diffraction (EBSD) and a material testing machine at room temperature. After extrusion, the Mg-6Bi-3Zn alloy possesses a bimodal microstructure with elongated large unrecrystallized (unDRXed) grains and fine dynamic recrystallized (DRXed) grains. In addition, non-basal <202_1>//ED, <448_3>//ED and <112_1>//ED textures are observed within DRXed grains due to the Zn addition, leading to texture weakening in the extruded Mg-6Bi-3Zn alloy. Zn addition facilitates the dynamic precipitation behavior, leading to a 12.2% area fraction of Mg3Bi2 precipitates with an average size of 39.2 nm. Furthermore, incorporation of Zn atoms in Mg3Bi2 phases and segregation of Zn at the grain boundary are found. The extruded Mg-6Bi-3Zn alloy exhibits a tensile strength of 336 ± 7.1 MPa and a yield strength of 290 ± 5.5 MPa, as well as an elongation of 11.5%. Therefore, Zn addition is beneficial to enhance strength and keep good ductility for the extruded Mg-6Bi-3Zn alloy.

16.
Sci Rep ; 14(1): 17925, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39095487

RESUMO

This study investigated the role of interfacial deformability in bond integrity and strength, particularly in the production of robust joints between harder austenitic stainless steels (SS) during ultrasonic welding. The specimen without the interlayer experienced limited strength enhancement owing to internal cracking from continuous sliding at interfacial temperatures below 0.6 times the melting point (Tm), which is attributed to the limited deformability of the austenitic SS. In contrast, introducing Fe and Ni interlayers between the substrates resulted in a notable increase in the interfacial strength, surpassing 2500 N in the peak load within a reduced welding duration. The correlation between the interfacial strength and the peak temperature suggests that a substantial decrease in hardness below 0.4 Tm is sufficient for extensive bond formation. Moreover, dynamic recrystallization (DRX) led to grain refinement in the Fe interlayer owing to shorter weld durations, whereas grain growth was observed in the Ni interlayer due to higher peak temperatures. Both the Fe and Ni interlayers significantly improved the bonding integrity by accommodating plasticity through the above phenomena without severe damage to the substrates, leading to increase of interfacial strength by 24% (2050 N to 2500 N) and reduction of weld duration by 40% (1.5 s in Fe interlayer). In addition, the fracture position after the lap shear test shifted from the edge of the weld area to the SS substrate.

17.
J Sci Food Agric ; 104(14): 8511-8518, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39031689

RESUMO

BACKGROUND: The cryoprotective effect of xylooligosaccharide (XO) and kappa-carrageenan (KC) mixture on silver carp proteins in fluctuated frozen storage from 4 to -18 °C was analyzed. Positive control as a conventional cryoprotectant mixture of sucrose (4%) and sorbitol (4%), KC (3%) and XO/KC (3%) treatments were incorporated in silver carp surimi and myofibrillar proteins to analyze the water mobility and its influence on structural attributes. RESULTS: The temperature fluctuation significantly increased the structural alteration in samples with no treatments due to oxidative changes, protein denaturation and recrystallization. Meanwhile, the mixture of XO and KC (XO/KC 3%) significantly reduced the tertiary and secondary structural alterations by preventing the oxidative changes in α-helix and tryptophan (Trp) residues. Moreover, XO/KC (3%) inhibited water mobility, hindering the T22 relaxation time, as compared to the samples added with KC (3%) and the positive control. Interestingly, the XO/KC (3%) mixture significantly reduced the formation of extracellular spaces and recrystallization by restricting the partial dehydration of muscles and extracellular solution concentration. CONCLUSION: From the current results, it can be concluded that the XO/KC mixture could be efficient in protecting aquatic food proteins during fluctuating frozen storage by preventing the exposure of Trp residues and α-helix contents. Moreover, XO/KC restricted the water mobility by establishing a bond and making water unavailable for crystallization and recrystallization. Therefore, XO/KC could be used as an effective mixture to prevent fluctuated and frozen storage changes in aquatic foods. © 2024 Society of Chemical Industry.


Assuntos
Carpas , Carragenina , Crioprotetores , Proteínas de Peixes , Armazenamento de Alimentos , Congelamento , Glucuronatos , Oligossacarídeos , Água , Animais , Carragenina/química , Oligossacarídeos/química , Água/química , Proteínas de Peixes/química , Crioprotetores/química , Crioprotetores/farmacologia , Glucuronatos/química , Conservação de Alimentos/métodos , Alimentos Marinhos/análise
18.
Angew Chem Int Ed Engl ; 63(42): e202406705, 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39049163

RESUMO

Solution-processed perovskite films generally possess small grain sizes and high density of grain boundaries, which intensify non-radiative recombination of carriers and limit the power conversion efficiency (PCE) of solar cells. In this study, we report the room-temperature ripening enabled by the synergy of hygroscopic salts and moisture in air for efficient hole-conductor-free printable mesoscopic perovskite solar cells (p-MPSCs). Treating perovskite films with proper hygroscopic salts in damp air induces obvious secondary recrystallization, which coarsens the grains size from hundreds of nanometers to several micrometers. It's proposed that the hygroscopic salt at grain boundaries could absorb moisture and form a complex which could not only serve as mass transfer channel but also assist in the dissolution of perovskite grains. This activates mass transfer between small grains and large grains since they possess different solubilities, and thus ripens the perovskite film. Consequently, p-MPSCs treated with the hygroscopic salt of NH4SCN show an improved power conversion efficiency of 20.13 % from 17.94 %, and maintain >98 % of the initial efficiency under maximum power point tracking at 55±5 °C for 350 hours.

19.
Int J Biol Macromol ; 276(Pt 2): 134047, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39033893

RESUMO

The study evaluated the effect of freezing rate on the quality of water-added quick-frozen rice noodles and water-free quick-frozen rice noodles. Results indicated that the retrogradation enthalpy, relative crystallinity, freezable water content, and cooking loss of water-added quick-frozen rice noodles were higher than those of water-free quick-frozen rice noodles with increasing storage time. Furthermore, ice recrystallization accelerated the deterioration of the quality of the rice noodles, resulting in the enlargement of the pores within the rice noodles and the formation of many pores on the surface. This phenomenon was particularly evident in the rice noodles of Y-40 °C (freezing with water at -40 °C) and Y-60 °C (freezing with water at -60 °C). After 28 days of frozen storage, the hardness increased by 83.83 % for rice noodles of Y-20 °C (freezing with water at -20 °C), while the hardness decreased by 51.68 % and 45.80 %, respectively, for rice noodles of Y-40 °C and Y-60 °C. Consequently, the impact of the freezing rate on the quality of water-added quick-frozen rice noodles is more pronounced than that of water-free quick-frozen rice noodles. Moreover, a higher freezing rate can delay the deterioration of the quality of frozen rice noodles by postponing starch retrogradation and inhibiting ice recrystallization.


Assuntos
Cristalização , Congelamento , Gelo , Oryza , Amido , Água , Oryza/química , Água/química , Amido/química , Gelo/análise
20.
Acta Crystallogr B Struct Sci Cryst Eng Mater ; 80(Pt 4): 305-310, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38958684

RESUMO

The synthesis of TaSe3 ring-shaped crystals displaying the coffee ring effect is investigated. By recrystallizing TaSe3 microcrystals dissolved in droplets of condensed Se gas, ring-shaped crystals were successfully grown. This novel method for ring formation effectively addressed the issue of connecting the edges of the crystal. Consequently, the synthesis method has the capability to grow MX3 ring-shaped crystals in any location where droplets can condense, can now be grown in specific locations, thus creating opportunities for advancements in electronic component development.

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