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1.
Int J Biol Macromol ; 279(Pt 4): 135322, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39236946

RESUMEN

The study aimed to investigating the mechanisms of relieved intestinal barrier damage by dynamic high-pressure microfluidization assisted with galactooligosaccharide- glycated whey protein isolate. The modifications changed the multi-structure, and the modified whey protein isolate could promote the proliferation of IEC-6 cells and contributed to the restoration of LPS-induced occludin damage in IEC-6 cells. Also, it could repair cyclophosphamide-induced ileal villus rupture and crypt destruction in BALB/c mice, significantly altered the abundance of dominant bacteria, which were associated with propionic acid, butyric acid, isovaleric acid, and valeric acid. Ileum transcriptomics revealed that the modified whey protein isolate significantly regulate of the levels of Cstad, Cyp11a1, and Hs6st2 genes, relating to the increase of propionic acid, isovaleric acid, and valeric acid. In conclusion, galactooligosaccharide- modified whey protein isolate could regulate the level of Cstad, Cyp11a1 and Hs6st2 genes by altering the gut microbial structure and the level of SCFAs, thereby repairing the intestinal barrier.

2.
Molecules ; 29(17)2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39274894

RESUMEN

Accurately measuring water holdup in horizontal wells is crucial for effectively using heavy oil reservoirs. The capacitance method is among the most widely used and accurate techniques. However, the absence of suitable insulating materials at high temperatures and pressures limits the effectiveness of capacitive water holdup measurement in heavy oil thermal recovery. This study introduces a new composite material based on an aviation-grade, special glass glaze as the insulating medium doped with inorganic components (CaSO4, MgSO4, Ca(OH)2, and SiO2). This new composite material demonstrates outstanding insulating performance under high-temperature and high-pressure conditions in water. A water environment with a high temperature of 350 °C and a pressure of 12 MPa considerably enhances the composite material's insulation. After 72 h of continuous use, the insulation performance remains 0.3 MΩ. The layers exhibit improved insulation and stability, maintaining integrity through five consecutive temperature shocks in 500 °C air and 20 °C water. XRD, IR, SEM, and TEM analyses reveal that the new composite material is amorphous after firing and that the addition of inorganic components improves the bonding between the glass glaze components and contributes to a denser structure. Simultaneously, SEM and TEM analyses indicate that adding inorganic components results in a smoother, crack-free, and more compact surface of the special glass glaze. This enhancement is crucial for the material's long-term stability in high-temperature and high-pressure water environments.

3.
Food Chem ; 463(Pt 2): 141180, 2024 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-39276541

RESUMEN

The effects of chickpea protein (CP) modified by heating and/or high-pressure homogenization (HPH) on the gelling properties of myofibrillar protein under reduced phosphate conditions (5 mM sodium triphosphate, STPP) were investigated. The results showed that heating and HPH dual-modified CP could decrease the cooking loss by 29.57 %, elevate the water holding capacity by 17.08 %, and increase the gel strength by 126.88 %, which conferred myofibrillar protein with gelation performance comparable with, or even surpassing, that of the high-phosphate (10 mM STPP) control. This gelation behavior improvement could be attributed to enhanced myosin tail-tail interactions, decreased myosin thermal stability, elevated trans-gauche-trans disulfide conformation, strengthened hydrophobic interactions and hydrogen bonding, the uncoiling of α-helical structures, the formation of well-networked myofibrillar protein gel, and the disulfide linkages between the myosin heavy chain, actin, and CP subunits. Therefore, the dual-modified CP could be a promising phosphate alternative to develop healthier meat products.

4.
Bioresour Technol ; : 131445, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39278365

RESUMEN

Carbon dioxide (CO2) biosynthesis is a promising alternative to traditional chemical synthesis. However, its application in engineering is hampered by poor gas mass transfer rates. Pressurization is an effective method to enhance mass transfer and increase synthesis yield, although the underlying mechanisms remain unclear. This review examines the effects of high pressure on CO2 biosynthesis, elucidating the mechanisms behind yield enhancement from three perspectives: microbial physiological traits, gas mass transfer and synthetic pathways. The critical role of pressurization in improving microbial activity and gas transfer efficiency is emphasized, with particular attention to maintaining pressure within microbial tolerance limits to maximize yield without compromising cell structure integrity.

5.
Food Chem X ; 23: 101774, 2024 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-39280230

RESUMEN

In recent years, the global mushroom industry has seen remarkable growth due to its nutritional benefits, increasing market value, and rising consumer demand. Mushrooms are valued for their unique flavor, low sugar and salt, and rich Vitamin D content. In India as well as across the globe, mushroom cultivation is becoming increasingly popular among new entrepreneurs, leveraging the diverse agro-climatic conditions and substantial agricultural waste. Various government policies are also fostering research and development in this sector. To extend shelf life and preserve quality, various preservation techniques are employed, including drying, freezing, canning, high-pressure processing and modified atmosphere packaging. Furthermore, cutting-edge technologies such as nuclear magnetic resonance and spectroscopy are improving post-harvest processing, helping to maintain sensory properties and nutritional content. Automation is also transforming mushroom processing by enhancing efficiency and scalability. This review examines the innovative methods and technologies driving advancements in mushroom production and quality worldwide.

6.
Sci Rep ; 14(1): 20712, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39237621

RESUMEN

Tight sandstone reservoirs are a primary focus of research on the geological exploration of petroleum. However, many reservoir classification criteria are of limited applicability due to the inherent strong heterogeneity and complex micropore structure of tight sandstone reservoirs. This investigation focused on the Chang 8 tight reservoir situated in the Jiyuan region of the Ordos Basin. High-pressure mercury intrusion experiments, casting thin sections, and scanning electron microscopy experiments were conducted. Image recognition technology was used to extract the pore shape parameters of each sample. Based on the above, through grey relational analysis (GRA), analytic hierarchy process (AHP), entropy weight method (EWM) and comprehensive weight method, the relationship index Q1 between initial productivity and high pressure mercury injection parameters and the relationship index Q2 between initial productivity and pore shape parameters are obtained by fitting. Then a dual-coupled comprehensive quantitative classification prediction model for tight sandstone reservoirs was developed based on pore structure and shape parameters. A quantitative classification study was conducted on the target reservoir, analyzing the correlation between reservoir quality and pore structure and shape parameters, leading to the proposal of favourable exploration areas. The research results showed that when Q1 ≥ 0.5 and Q2 ≥ 0.5, the reservoir was classified as type I. When Q1 > 0.7 and Q2 > 0.57, it was classified as type I1, indicating a high-yield reservoir. When 0.32 < Q1 < 0.47 and 0.44 < Q2 < 0.56, was classified as type II. When 0.1 < Q1 < 0.32 and 0.3 < Q2 < 0.44, it was classified as type III. Type I reservoirs exhibit a zigzag pattern in the northwest part of the study area. Thus, the northwest should be prioritized in actual exploration and development. Additionally, the initial productivity of tight sandstone reservoirs showed a positive correlation with the porosity, permeability, sorting coefficient, coefficient of variation, and median radius. Conversely, it demonstrated a negative correlation with the median pressure and displacement pressure. The perimeters of pores, their circularity, and the length of the major axis showed a positive correlation with the porosity, permeability, sorting coefficient, coefficient of variation, and median radius. On the other hand, they exhibited a negative correlation with the median pressure and displacement pressure. This study quantitatively constructed a new classification and evaluation system for tight sandstone reservoirs from the perspective of microscopic pore structure, achieving an overall model accuracy of 93.3%. This model effectively predicts and evaluates tight sandstone reservoirs. It provides new guidance for identifying favorable areas in the study region and other tight sandstone reservoirs.

7.
Swiss J Geosci ; 117(1): 15, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39220266

RESUMEN

Relicts of subducted oceanic lithosphere provide key information for the tectonic reconstructions of convergent margins. In the Central Alps, such relicts occur as isolated mafic-ultramafic lenses within the migmatites of the southern Adula nappe and Cima-Lunga unit. Analysis of the major-, minor-, and accessory minerals of these ophiolitic relicts, combined with zircon and rutile U-Pb ages and zircon oxygen isotopes, allows the reconstruction of different stages of their complex evolution. The mafic-ultramafic suite in Valle di Moleno consists of chlorite-harzburgites associated with metarodingites and retrogressed eclogites. Relic omphacite and kyanite in retrogressed eclogites provide evidence for subduction-related metamorphism. Increasing XPrp in the garnet mantle towards the rim documents heating during high-pressure metamorphism up to 800-850 °C. Polyphase inclusions and chemical zoning in garnet suggest fluid-assisted melting during high-pressure metamorphism dated at 31.0 ± 0.9 Ma. In Val Cama, chlorite-harzburgites, metarodingites and calcsilicate-metasediments occur. Detrital zircon ages in the metasediment suggest a Mesozoic deposition. The metarodingite-metaperidotite-metasediment association and the low δ18O signatures of zircon (δ18O 3.0-3.7‰), inherited from seafloor metasomatism of the protoliths, show that the rocks are derived from former altered oceanic crust. Amphibolite facies metamorphism related to the Central Alps Barrovian evolution in Val Cama occurred at 28.8 ± 1.5 Ma. The combined data from Moleno and Cama indicate a rapid transition (~ 2 Ma) from subduction to collisional metamorphism with corresponding exhumation rates of 3-6 cm/year. Fast exhumation tectonics may have been favored by slab break-off or slab extraction. U-Pb dating of rutile from both localities yields ages of ~ 20 Ma, suggesting that these rocks remained at amphibolite-facies conditions for about 10 Ma and underwent a second fast exhumation of 3 cm/year associated with vertical movements along the Insubric line. Supplementary Information: The online version contains supplementary material available at 10.1186/s00015-024-00462-7.

8.
Interv Cardiol ; 19: e13, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39221062

RESUMEN

Coronary calcification represents a significant technical challenge in percutaneous coronary intervention and is associated with worse clinical outcomes. Fortunately, a number of balloon-assisted technologies are available to aid in the management of coronary calcification before stenting. Adequate lesion preparation is crucial in the successful management of calcified coronary lesions. Balloon-based techniques can be a safe and effective method of lesion preparation and, as such, are an integral part of an interventionalist's armamentarium. In this mini-review, we focus on the use of non-compliant balloons, super high-pressure non-compliant balloons, cutting balloons, scoring balloons and intravascular lithotripsy.

9.
Food Res Int ; 194: 114913, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39232536

RESUMEN

The formation of starch-polyphenol complexes through high-pressure homogenization (HPH) is a promising method to reduce starch digestibility and control postprandial glycemic responses. This study investigated the combined effect of pH (5, 7, 9) and polyphenol structures (gallic acid, ferulic acid, quercetin, and tannic acid) on the formation, muti-scale structure, physicochemical properties, and digestibility of pea starch (PS)-polyphenol complexes prepared by HPH. Results revealed that reducing pH from 9 to 5 significantly strengthened the non-covalent binding between polyphenols and PS, achieving a maximum complex index of 13.89 %. This led to the formation of complexes with higher crystallinity and denser structures, promoting a robust network post-gelatinization with superior viscoelastic and thermal properties. These complexes showed increased resistance to enzymatic digestion, with the content of resistant starch increasing from 28.66 % to 42.00 %, rapidly digestible starch decreasing from 42.82 % to 21.88 %, and slowly digestible starch reducing from 71.34 % to 58.00 %. Gallic acid formed the strongest hydrogen bonds with PS, especially at pH 5, leading to the highest enzymatic resistance in PS-gallic acid complexes, with the content of resistant starch of 42.00 %, rapidly digestible starch of 23.35 % and slowly digestible starch of 58.00 %, and starch digestion rates at two digestive stages of 1.82 × 10-2 min-1 and 0.34 × 10-2 min-1. These insights advance our understanding of starch-polyphenol interactions and support the development of functional food products to improve metabolic health by mitigating rapid glucose release.


Asunto(s)
Digestión , Ácido Gálico , Pisum sativum , Polifenoles , Almidón , Concentración de Iones de Hidrógeno , Polifenoles/química , Almidón/química , Almidón/metabolismo , Pisum sativum/química , Ácido Gálico/química , Taninos/química , Presión , Ácidos Cumáricos/química , Manipulación de Alimentos/métodos , Quercetina/química
10.
Water Environ Res ; 96(9): e11111, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39229823

RESUMEN

Due to the overexploitation of deep groundwater, the largest cone of depression in the world has formed in the North China Plain. This led to severe geological hazards, including land subsidence and ground fissures, and also caused economic losses. The prevention and treatment of subsidence needs to rely on the accurate prediction of subsidence amount. According to the one-dimensional consolidation theory and effective stress principle, combined with stratum structure, groundwater flow, stress distribution, and so forth, the high-pressure consolidation test results of 569.6 m deep borehole soil samples are adopted; with a specific focus on stress and deformation parameters under exploitation of groundwater condition, the soil-water coupling prediction model of groundwater level lowering depth and land subsidence has been established. Verification with measured subsidence data near the study sites demonstrated that the predicted curve is consistent with the measured one and the differences between them are acceptable. The model can be applied in different areas after making adjustment based on different regional stratigraphic structures. Its key advantage lies in the ability to provide land subsidence prediction for areas lacking monitoring data, making it highly valuable for widespread application. PRACTITIONER POINTS: There is a compressible stratum structure; it is the internal factors of land subsidence. The groundwater level decline causes the soil body stress to change. It is land subsidence of the external factors. Based on the one-dimensional consolidation theory and by combining stratigraphic structures, groundwater flow, and stress distribution, a ground settlement prediction model was established.


Asunto(s)
Agua Subterránea , Suelo , Suelo/química , China , Modelos Teóricos , Movimientos del Agua , Monitoreo del Ambiente
11.
Food Chem ; 463(Pt 1): 141078, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39243612

RESUMEN

A comprehensive comparison was conducted on the effect of conventional thermal processing (TT), high-pressure processing (HP), pulse electric field (PF), and ohmic heating (OH) on water-soluble vitamins and color retention in strawberry nectar. The ascorbic acid (AA) content increased by 15- and 9-fold after TT and PF treatment, respectively, due to rupturing of cells under heat stress and release of intracellular AA. Dehydroascorbic acid (DHA) content did not change considerably after TT and PF treatment but significantly decreased after HP and OH treatment. TT treatment offered the highest total vitamin C retention. The B vitamins remained largely unchanged after processing, with the highest loss of 34 % for riboflavin in OH-treated samples. All the technologies resulted in similar color retention after processing. The study concludes with a standardized comparison of mainstream preservation technologies using pilot-scale equipment. Such an approach significantly increases the applicability of the results presented in the study.

12.
Food Sci Anim Resour ; 44(5): 967-987, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39246541

RESUMEN

Recently, as the concept of pet food that satisfies both nutritional needs and the five senses has evolved, so too has the demand for effective pet food non-thermal sterilization methods. Prominent non-thermal technologies include high-pressure processing, plasma, and radiation, which are favored for their ability to preserve nutrients, avoid residues, and minimize compositional changes, thereby maintaining quality and sensory properties. However, to assess their effectiveness on pet food, it is essential to optimize operational parameters such as pressure levels, plasma intensity, radiation dosage, and temperature. Further studies are needed to evaluate microbial sterilization efficacy and sensory attributes. This exploration is expected to lay the groundwork for preventing zoonotic diseases and improving the production of high-quality pet food.

13.
Bioresour Technol ; 413: 131421, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39233186

RESUMEN

Anaerobic digestion (AD) is an environmentally friendly technology that simultaneously stabilizes biowaste and produces biogas. Conventional AD faces challenges such as inadequate substrate degradation and low methane purity. Pressure-centric regulation serves as an AD optimization strategy that can enhance the digestion efficiency and generate higher-energy-value biogas. However, limited reviews have been undertaken to focus on this technology. This review is designed to discuss innovations in ex-situ high-pressure pretreatment and in-situ high-pressure anaerobic digestion (HPAD) processes. Moreover, comprehensive understandings on the intrinsic mechanisms of HPAD are critically examined, including physicochemical reaction principles and microbial responses. The constraints currently curtailing these technologies and potential mitigation strategies are also scrutinized. Additionally, current knowledge gaps and future research directions on mechanisms, model fitting, and engineering practices are presented. Overall, this work highlights the feasibility of pressure-centric regulated AD and provides novel insights to overcome existing technical barriers in its application.

14.
J Vasc Access ; : 11297298241272259, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39258587

RESUMEN

PURPOSE: To compare primary patency after angioplasty with drug-coated balloon (DCB)-Passeo-18Lux, BIOTRONIK versus uncoated balloon in dysfunctional peripheral vascular access (PVA) for hemodialysis. MATERIAL AND METHODS: A total of 133 patients from four hospitals were randomized to receive DCB or plain old balloon angioplasty (POBA) after satisfactory treatment (residual stenosis <30%) with high pressure balloon (HPB). The primary endpoint was clinical patency of PVA 2 years after angioplasty. Secondary endpoints included the relationship between the location of stenosis and patency and also, other covariates. Mortality at 2 years was compared between both groups. RESULTS: Patency measured in days after angioplasty was higher in fistulae dilated with DCB than HPB. Kaplan-Meier survival curves showed the next percent of success (free time restenosis) after DCB versus POBA at 6 months-77.1% versus 58.2% (160.41-143.72 days until restenosis), 12 months-51.4% versus 44.3% (274.1-237.23), 18 months-38.6% versus 38% (350.74-305.18), and 24 months-37.1% versus 30.4% (419.04-369.1). At 6 months, this difference was statistically significant (p = 0.018), but not at 12 (p = 0.225), 18 (p = 0.471), or 24 months (p = 0.236). Mortality was similar in both groups. CONCLUSIONS: DCB angioplasty resulted in superior target lesion primary patency (TLPP)-free survival at 6 months of follow-up. No significant improvements in TLPP-free survival long term were observed. Mortality observed at 1 and 2 years was similar in DCB and POBA: there was no significant difference, and a safety study demonstrated no difference between the two groups (complications and mortality): DCB is safe to use in stenosis treatment in patients who are PVA carriers. LEVEL OF EVIDENCE: Level Ia, therapeutic study, RCT. EBM ratings will be based on a scale of 1-5.

15.
J Sci Food Agric ; 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39105678

RESUMEN

BACKGROUND: The process of Maillard conjugation occurs with plant proteins and sugars and can be influenced by several factors, such as processing time, pH, and shear force. By utilizing cavitation processes such as high-pressure homogenization (HPH) and pH-shifting, it is possible to regulate the degree of grafting, functional characteristics, and structural changes in the formation of conjugates. The present study aimed to improve the hemp protein concentrate (HPC) through two different conjugation techniques: HPH and pH-shifting-assisted processes. RESULTS: The best conjugation conditions for the conventional method were identified as a 1:2 HPC to xylose ratio, a pH of 10, and 3 h of treatment at 70 °C. The use of HPH and pH 12-shifting methods resulted in a remarkable 2.5-fold increase in grafting degree, requiring less processing time. Fourier transform infrared spectra confirmed the formation of conjugates. Conjugates produced through HPH with pH 12-shifting (MPHX) transformed into soluble glycoproteins with a particle size of 74 nm. MPHX solubility increased by 5.7-fold than HPC, reaching 85.7%, with a more negatively charged surface at -32.4 mV. Microimages showed cracked and sharp forms for conjugated proteins compared to untreated HPC. Additionally, MPHX conjugates demonstrated superior properties in emulsion stability, foaming capacity, and antioxidant activity compared to HPC and classical conjugates. CONCLUSION: The use of HPH and pH-shifting-assisted Maillard conjugation was highly effective in enhancing the functional attributes of hemp protein conjugates. © 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

16.
J Appl Crystallogr ; 57(Pt 4): 1217-1228, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39108808

RESUMEN

Presented and discussed here is the implementation of a software solution that provides prompt X-ray diffraction data analysis during fast dynamic compression experiments conducted within the dynamic diamond anvil cell technique. It includes efficient data collection, streaming of data and metadata to a high-performance cluster (HPC), fast azimuthal data integration on the cluster, and tools for controlling the data processing steps and visualizing the data using the DIOPTAS software package. This data processing pipeline is invaluable for a great number of studies. The potential of the pipeline is illustrated with two examples of data collected on ammonia-water mixtures and multiphase mineral assemblies under high pressure. The pipeline is designed to be generic in nature and could be readily adapted to provide rapid feedback for many other X-ray diffraction techniques, e.g. large-volume press studies, in situ stress/strain studies, phase transformation studies, chemical reactions studied with high-resolution diffraction etc.

17.
Angew Chem Int Ed Engl ; : e202412756, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39107973

RESUMEN

Simultaneous enhancement of free excitons (FEs) emission and self-trapped excitons (STEs) emission remains greatly challenging because of the radiative pathway competition. Here, a significant fluorescence improvement, associated with the radiative recombination of both FEs and STEs is firstly achieved in an unconventional ACI-type hybrid perovskite, (ACA)(MA)PbI4 (ACA=acetamidinium) crystals with {PbI6} octahedron units, through hydrostatic pressure processing. Note that (ACA)(MA)PbI4 exhibits a 91.5-fold emission enhancement and considerable piezochromism from green to red in a mild pressure interval of 1 atm to 2.5 GPa. The substantial distortion of both individual halide octahedron and the Pb-I-Pb angles between two halide octahedra under high pressure indeed determines the pressure-tuning localized excitons behavior. Upon higher pressure, photocurrent enhancement is also observed, which is attributed to the promoted electronic connectivity in (ACA)(MA)PbI4. The anisotropic compaction reduces the distance between neighboring organic molecules and {PbI6} octahedra, leading to the enhancement of hydrogen bonding interactions. This work not only offers a deep understanding of the structure-optical relationships of ACI-type perovskites, but also presents insights into breaking the limits of luminescent efficiency by pressure-suppressed nonradiative recombination.

18.
J Hand Surg Glob Online ; 6(4): 540-544, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39166208

RESUMEN

Purpose: High-pressure injection injuries are a rare, and potentially serious, trauma that has historically been associated with high-amputation rates. This study aimed to assess the amputation rates, materials involved, and outcomes at a single institution. Methods: A retrospective analysis of 53 cases at a level-1 trauma center in South Central Texas between 2007 and 2023 was conducted. Patient demographics, injury details, materials injected, surgical interventions, complications, and follow-up data were collected and analyzed. Results: There was an amputation rate of 2.2. Latex-based paints showed more favorable outcomes when compared with grease injections and oil-based paints. There were also fewer reoperations and postoperative complications with latex-based paint injuries. Conclusions: The study signals the need for a re-evaluation of high-pressure injection injury outcomes, highlighting a more optimistic prognosis than previously thought. The evolution of materials in paints, especially latex-based paints, may have been associated with a lower rate of amputation than what was previously reported. Type of study/level of evidence: Prognostic IV.

19.
Adv Mater ; : e2407249, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39194637

RESUMEN

The realization of spontaneous ferroelectricity down to the one-dimensional (1D) limit is both fundamentally intriguing and practically appealing for high-density ferroelectric and nonlinear photonics. However, the 1D vdW ferroelectric materials are not discovered experimentally yet. Here, the first 1D vdW ferroelectric compound NbOI3 with a high Curie temperature TC > 450 K and giant second harmonic generation (SHG) is reported. The 1D crystalline chain structure of the NbOI3 is revealed by cryo-electron microscopy, whereas the 1D ferroelectric order originated from the Nb displacement along the Nb-O chain (b-axis) is confirmed via obvious electrical and ferroelectric hysteresis loops. Impressively, NbOI3 exhibits a giant SHG susceptibility up to 1572 pm V-1 at a fundamental wavelength of 810 nm, and a further enhanced SHG susceptibility of 5582 pm V-1 under the applied hydrostatic pressure of 2.06 GPa. Combing in situ pressure-dependent X-ray diffraction, Raman spectra measurements, and first-principles calculations, it is demonstrated that the O atoms shift along the Nb─O atomic chain under compression, which can lead to the increased Baur distortion of [NbO2I4] octahedra, and hence induces the enhancement of SHG. This work provides a 1D vdW ferroelectric system for developing novel ferroelectronic and photonic devices.

20.
Chemistry ; : e202402741, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39196605

RESUMEN

Nitridophosphates are subject of current research, as they have a broad spectrum of properties and potential applications, such as ion conductors or luminescent materials. Yet, the subclass of imidonitridophosphates has been studied less extensively. The primary reason is that the controlled N-H functionalization of nitridophosphates is not straight forward, making targeted synthesis more challenging. Inspired by the high-pressure (HP) post-synthetic modification of nitridophosphates, we present the topochemical HP deprotonation of phosphorus nitride imides using the high-pressure polymorph ß-PN(NH) as an example. Additional incorporation of Zn2+ results in the first quaternary transition metal imidonitridophosphate ZnH2P4N8. The crystal structure was elucidated by single-crystal X-ray diffraction (SCXRD), energy-dispersive X-ray spectroscopy (EDX), powder X-ray diffraction (PXRD) and solid-state magic angle spinning nuclear magnetic resonance spectroscopy (MAS NMR). In addition, the presence of H as part of an imide group was confirmed by IR spectroscopy. The potential of this defunctionalization approach for controlling the N-H content is demonstrated by the preparation of partially deprotonated intermediates ZnxH4-2xP4N8 (x ≈  0.5, 0.85). This topochemical high-pressure reaction represents a promising way to prepare, control and manipulate new imide-based materials without altering their overall anionic framework.

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