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1.
Sci Rep ; 14(1): 22825, 2024 Oct 01.
Article in English | MEDLINE | ID: mdl-39354044

ABSTRACT

The pore-throat structure is a crucial parameter for evaluating reservoir characteristics and assessing the potential of oil and gas resources. Understanding the relationship between reservoir pore-throat variations and oil-bearing properties is essential. Through a combination of techniques, including thin-section casting, scanning electron microscopy (SEM), micro-computed tomography (micro-CT), and high-pressure mercury injection (HPMI), we examined the tight sandstone reservoirs from the Chang 4 + 5 members of the Yanchang Formation in the study area. This analysis elucidates the relationship between the pore-throat structure and fractal characteristics of the samples and their oil-bearing properties. The results show that : (1) The tight sandstone reservoirs in the study area mainly develop three types of pores: dissolution pores, residual intergranular pores, and microfractures. Residual intergranular pores are primarily controlled by early compaction processes, while dissolution processes easily form secondary pores, increasing the porosity of the reservoir. Microfractures can significantly enhance both the permeability of the reservoir. (2) Using the characteristic parameters of HPMI, the reservoir is classified into four categories, labeled as type I to type IV. As the categories progress from type I to type IV, pore-throat size decreases, porosity and permeability decrease, and reservoir properties deteriorate. The overall fractal dimension of pores decreases, while the fractal dimensions of individual pore types increase. Pore connectivity becomes more complex, and heterogeneity strengthens. (3) Reservoir porosity shows a strong positive correlation with permeability. As reservoir properties improve, the number of macropores increases, leading to a higher Reservoir Quality Index (RQI) and better oil-bearing characteristics.

2.
J Appl Crystallogr ; 57(Pt 5): 1436-1445, 2024 Oct 01.
Article in English | MEDLINE | ID: mdl-39387076

ABSTRACT

High-pressure neutron powder diffraction data from PbNCN were collected on the high-pressure diffraction beamline SNAP located at the Spallation Neutron Source (SNS) of Oak Ridge National Laboratory (Tennessee, USA). The diffraction data were analyzed using the novel method of multidimensional (two dimensions for now, potentially more in the future) Rietveld refinement and, for comparison, employing the conventional Rietveld method. To achieve two-dimensional analysis, a detailed description of the SNAP instrument characteristics was created, serving as an instrument parameter file, and then yielding both cell and spatial parameters as refined under pressure for the first time for solid-state cyanamides/carbodi-imides. The bulk modulus B 0 = 25.1 (15) GPa and its derivative B'0 = 11.1 (8) were extracted for PbNCN following the Vinet equation of state. Surprisingly, an internal transition was observed beyond 2.0 (2) GPa, resulting from switching the bond multiplicities (and bending direction) of the NCN2- complex anion. The results were corroborated using electronic structure calculation from first principles, highlighting both local structural and chemical bonding details.

3.
J Appl Crystallogr ; 57(Pt 5): 1691-1696, 2024 Oct 01.
Article in English | MEDLINE | ID: mdl-39387082

ABSTRACT

High-pressure crystallographic data can be measured using a diamond anvil cell (DAC), which allows the sample to be viewed only along a cell vector which runs perpendicular to the diamond anvils. Although centring a sample perpendicular to this direction is straightforward, methods for centring along this direction often rely on sample focusing, measurements of the direct beam or short data collections followed by refinement of the crystal offsets. These methods may be inaccurate, difficult to apply or slow. Described here is a method based on precise measurement of the offset in this direction using a confocal optical device, whereby the cell centre is located at the mid-point of two measurements of the distance between a light source and the external faces of the diamond anvils viewed along the forward and reverse directions of the cell vector. It is shown that the method enables a DAC to be centred to within a few micrometres reproducibly and quickly.

4.
Int J Biol Macromol ; : 136462, 2024 Oct 09.
Article in English | MEDLINE | ID: mdl-39393742

ABSTRACT

This study investigated the impact of high-pressure processing (HPP) treatment on the structure and physicochemical properties of pectin (PEC)/carboxymethyl cellulose (CMC) composite films, along with the development of new active films incorporating emodin as an antibacterial agent. The results showed that 500 MPa/20 min HPP treatment significantly improved the tensile strength (from 45.91 ±â€¯4.63 MPa to 52.24 ±â€¯4.87 MPa) and elongation at the break (from 5.00 ±â€¯1.44 % to 11.72 ±â€¯2.97 %) of the films. It also improved the film's thermal stability and had no significant effect on its thermal degradability. Moreover, emodin was incorporated into the PEC/CMC film-forming solution and subjected to 500 MPa/20 min HPP treatment to investigate the structure, functional properties, optical properties, and antibacterial activity of the film. The emodin caused the film structural alteration, but significantly improved the water vapor barrier properties. It also reduced the film brightness and light transmission. The antibacterial assessment demonstrated that the film's antibacterial activity was correlated positively with increasing emodin content, and the number of viable cells of Staphylococcus aureus decreased by 1.29 log10 CFU/mL, 1.70 log10 CFU/mL, and 1.80 log10 CFU/mL with different levels of EM antimicrobial films after 12 h.

5.
Clin Chim Acta ; 565: 119987, 2024 Oct 03.
Article in English | MEDLINE | ID: mdl-39368684

ABSTRACT

Mucopolysaccharidosis type IIIA is a lysosomal storage disorder caused by mutations in the gene coding for heparan-N-sulphatase, a crucial enzyme in the degradation of heparan sulfate. In mucopolysaccharidosis type IIIA, heparan sulfate accumulates in the lysosomes, predominantly affecting the central nervous system. It is the most common and most severe form of mucopolysaccharidosis type III, with onset typically before the age of ten years. There is an ongoing effort to develop therapies that aim at restoring enzyme function in the brain. This study introduces a novel tandem mass spectrometry method for assessing heparan-N-sulphatase activity in pediatric cerebrospinal fluid from healthy and disease individuals. Analysis of cerebrospinal fluid samples revealed marked differences in enzyme activity, with mucopolysaccharidosis type IIIA individuals exhibiting significantly reduced levels. This new method could serve as a valuable tool for evaluating the efficacy of future therapeutic interventions targeting sulphatase activity restoration in the brain.

6.
Article in English | MEDLINE | ID: mdl-39405198

ABSTRACT

The crystal structure of the incommensurate modulated phase of potassium guaninate monohydrate has been solved on the basis of high-pressure single-crystal X-ray diffraction data. The modulated structure was described as a `mosaic' sequence of three different local configurations of two neighbouring guaninate rings. In contrast to known examples of incommensurate modulated organic compounds, the modulation functions of all atoms are discontinuous. This is the first example of the experimental detection of an incommensurate modulated crystal structure that can be modelled using the special `soliton mode' modulation function proposed by Aramburu et al. [(1995), J. Phys. Condens. Matter, 7, 6187-6196].

7.
Proc Natl Acad Sci U S A ; 121(42): e2408119121, 2024 Oct 15.
Article in English | MEDLINE | ID: mdl-39383004

ABSTRACT

Strong steels are primarily fabricated by introducing spatial obstacles (e.g., stacking faults and precipitates) that inhibit dislocation slips under stress to achieve high strength. However, for most low-carbon steels, such obstacles are difficult to form mainly because the martensitic transition is kinetically unfavorable by conventional methods, which precludes the attainment of high-strength materials in these steels with low solute contents. Here, we report an innovative high-pressure preparation of martensitic pure Fe with involving nano-effect, which leads to the formation of ultrastrong bulk iron with exceptionally high yield strength, ultimate strength, and hardness of 2.9 GPa, 3.7 GPa, and 9.0 GPa, respectively, exceeding those of high-speed steels. Such extraordinary mechanical properties are closely attributed to its high-density martensites with unique multiscale hierarchical structures formed due to complex phase transitions under pressure.

8.
J Food Sci Technol ; 61(11): 2215-2221, 2024 Nov.
Article in English | MEDLINE | ID: mdl-39397844

ABSTRACT

This investigation employed different ANN infrastructures for predicting the quality of sugarcane juice under varying microfluidization pressures (50-200 MPa) and cycles (1-7) which was previously unexplored. Two hidden layer (HL) activation functions (tansigmoid, logsigmoid) and learning algorithms (LM, GDX) with varying hidden layer neurons (HLNs) were tested to predict the color, total phenol content, total flavonoid content, chlorophyll content, total and reducing sugars, polyphenol oxidase activity, peroxidase activity, sucrose neutral invertase activity, aerobic plate count, yeast and mold count, particle size, sensory score and sedimentation rate of sugarcane juice under different microfluidization processing conditions. Results showed that the combination of LM + logsigmoid, GDX + logsigmoid and GDX + tansigmoid produced > 90% prediction accuracy. Among these models, GDX + tansigmoid exhibited 91.7% accuracy on training, and 96% accuracy on testing using relatively lower number of neurons (10 HLNs), and was therefore selected to predict the quality characteristics of sugarcane juice. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-024-05994-2.

9.
Int J Biol Macromol ; : 136528, 2024 Oct 12.
Article in English | MEDLINE | ID: mdl-39401637

ABSTRACT

Numerous surfactants, nanoparticles and polymers have been developed and utilized for enhanced oil recovery applications, irrespective of their environmental impact. Most of these oilfield chemicals were prepared through multi-steps from fossil-based starting materials using hazardous solvents. However, there is a desire to advance eco-friendly and sustainable materials to reduce CO2 emissions and enhance the sustainability of oil production. Herein, we propose the development of chitosan salt, a solely green polymer, prepared in water in the presence of acetic acid (0.1 % v/v). The resulting water-soluble polymer demonstrated excellent stability under reservoir conditions and was tested for enhanced oil recovery in the carbonate reservoir. The oil-wet rock wettability was significantly reduced after using chitosan salt solution. Nuclear magnetic resonance (NMR) experiments were used to show the oil displacement at different pores regions using relaxation time (T2 distribution). Imbibition and coreflooding experiments showed that the chitosan salt is able to increase the enhanced oil recovery by extra 16.2 % which surpass the recovery obtained from commercial surfactants such as α-olefin sulfonate (AOS) and cetrimonium bromide (CTAB). This study shows that green materials are promising candidates oil recovery and upstream applications.

10.
Bioresour Technol ; 414: 131619, 2024 Oct 10.
Article in English | MEDLINE | ID: mdl-39393644

ABSTRACT

In the present work, two downstream processes - high-pressure homogenization at 100 (HPH-100) and 1200 bar (HPH-1200), and enzymatic hydrolysis (EH) - were tested to produce biostimulant extracts from Tetradesmus obliquus grown in piggery wastewater at two concentrations (12.8 and 88.3 g/L). Extracts before and after centrifugation (C) were evaluated in four bioassays using garden cress (germination), mung bean (auxin-like activity), and cucumber (auxin- and cytokinin-like activity) relative to distilled water. The initial microalgal culture, without any treatment, had the best germination results (162 % at 0.2 g/L) and the only one that showed cytokinin-like activity (141 % at 0.5 g/L). In both auxin-like bioassays, the HPH-1200 + C and EH + C originated high values (186 and 155 % for cucumber, 290 and 285 % for mung bean, respectively). For mung bean, the HPH-1200 achieved the highest auxin-like effect (378 %). Finally, the extracted biomass contained essential nutrients for biofertilization, complementing the biostimulant extracts for sustainable agriculture application.

11.
EJNMMI Radiopharm Chem ; 9(1): 70, 2024 Oct 15.
Article in English | MEDLINE | ID: mdl-39405010

ABSTRACT

BACKGROUND: Technetium-99 m-labelled macroaggregated human serum albumin ([99mTc]Tc-MAA) is commonly used for lung perfusion scintigraphy. The European Pharmacopoeia (Eu.Ph.) specifies thin-layer chromatography (TLC) as the only method to assess its radiochemical purity (RCP). Similarly, TLC is the sole method reported in the literature to evaluate the RCP of Gallium-68-labelled MAA [68 Ga]Ga-MAA, recently introduced for lung perfusion PET/CT imaging. Since [68 Ga]Ga-MAA is prepared from commercial kits originally designed for the preparation of [99mTc]Tc-MAA, it is essential to optimize and validate the preparation methods for [68 Ga]Ga-MAA. RESULTS: We tested a novel, simplified method for the preparation of [68 Ga]Ga-MAA that does not require organic solvents, prewash or final purification steps to remove radioactive impurities. We assessed the final product using radio-TLC, radio-UV-HPLC, and radio SDS-PAGE. Overall, our quality control (QC) method successfully detected [68 Ga]Ga-MAA along with all potential impurities, including free Ga-68, [68 Ga]Ga-HSA, unlabeled HSA, which may occur during labelling process and HEPES residual, a non-toxic but non-human-approved contaminant, used as buffer solution. We then applied our QC system to [68 Ga]Ga-MAA prepared under different conditions (25°-40°-75°-95 °C), thus defining the optimal temperature for labelling. Scanning Electron Microscopy (SEM) analysis of the products obtained through our novel method confirmed that most [68 Ga]Ga-MAA particles preserved the morphological structure and size distribution of unlabeled MAA, with a particle diameter range of 25-50 µm, assuring diagnostic efficacy. CONCLUSIONS: We optimized a novel method to prepare [68 Ga]Ga-MAA through a QC system capable of monitoring all impurities of the final products.

12.
Foods ; 13(19)2024 Sep 24.
Article in English | MEDLINE | ID: mdl-39410062

ABSTRACT

The paper presents the 'progressive review' for high pressure preservation/processing (HPP) (cold pasteurization) of foods and the next-generation high-pressure and high temperature (HPHT, HPT) food sterilization technologies. It recalls the basics of HPP and HPT, showing their key features and advantages. It does not repeat detailed results regarding HPP and HPT implementations for specific foods, available in numerous excellent review papers. This report focuses on HPP and HPT-related issues that remain challenging and can hinder further progress. For HPP implementations, the reliable modeling of microorganisms' number decay after different times of high pressure treatment or product storage is essential. This report indicates significant problems with model equations standard nonlinear fitting paradigm and introduces the distortion-sensitive routine enabling the ultimate validation. An innovative concept based on the barocaloric effect is proposed for the new generation of HPT technology. The required high temperature appears only for a strictly defined short time period controlled by the maximal pressure value. Results of the feasibility test using neopentyl glycol as the barocaloric medium are presented. Attention is also paid to feedback interactions between socioeconomic and technological issues in the ongoing Industrial Revolution epoch. It indicates economic constraints for HPP and HPT developments and emerging business possibilities. The discussion recalls the inherent feedback interactions between technological and socioeconomic innovations as the driving force for the Industrial Revolution epoch.

13.
Foods ; 13(19)2024 Sep 29.
Article in English | MEDLINE | ID: mdl-39410154

ABSTRACT

The impact of the roasting degree on ultra-high-pressure cold brew (UHP) coffee remains unclear, although it has been found that UHP technology accelerates the extraction of cold brew (CB) coffee. Therefore, this study investigated the effects of three different degrees of roasting (light, medium, and dark) on the physicochemical characteristics, volatile and non-volatile components, and sensory evaluation of UHP coffee. Orthogonal partial least-squares-discriminant analysis (OPLS-DA) and principal component analysis (PCA) were used to assess the effects of different roasting degrees. The results showed that most physicochemical characteristics, including total dissolved solids (TDSs), extraction yield (EY), total titratable acidity (TTA), total sugars (TSs), and total phenolic content (TPC), of UHP coffee were similar to those of conventional CB coffee regardless of the degree of roasting. However, the majority of physicochemical characteristics, non-volatile components, including the antioxidant capacity (measured based on DPPH and ABTS) and melanoidin, caffeine, trigonelline, and CGA contents increased significantly with an increase in roasting degree. The sensory evaluation revealed that as the roasting degree rose, the nutty flavor, astringency, bitterness, body, and aftertaste intensities increased, while floral, fruity, and sourness attributes decreased. The HS-SPME-GC/MS analysis showed that most volatile components increased from light to dark roasting. Moreover, 15 representative differential compounds, including hazelnut pyrazine, linalool, butane-2,3-dione, and 3-methylbutanal, were identified by calculating the odor-active values (OAVs), indicating that these contributed significantly to the odor. The PCA showed that the distance between the three roasting degree samples in UHP coffee was smaller than that in CB coffee. Overall, the effect of roasting degrees on UHP coffee was less than that on CB coffee, which was consistent with the results of physicochemical characteristics, volatile components, and sensory evaluation.

14.
Foods ; 13(19)2024 Oct 06.
Article in English | MEDLINE | ID: mdl-39410209

ABSTRACT

Coconut chips are a popular leisure food, but the residual crumbly feeling after chewing affects the eating experience. To address this problem, we investigated the mechanism of degradation of insoluble dietary fiber (IDF) from coconut chips by ultra-high pressure (UHP). The optimal conditions for UHP treatment were 100 MPa and 40 min. After UHP treatment, the hardness decreased by 60%, and the content of soluble dietary fiber (SDF) increased by 55%. So far, the meaning of SDF has not been defined. The microstructure of IDF was damaged and the surface was rough. There was no obvious change in the chemical structure. The position of the characteristic diffraction peaks was basically unchanged, but the crystallinity dropped by almost three times. The thermal stability decreased, and the composition of the monosaccharides changed. Together, UHP treatment can improve the problem of the residual crumbly feeling after chewing coconut chips and improve the quality of the product.

15.
Adv Sci (Weinh) ; : e2410099, 2024 Oct 16.
Article in English | MEDLINE | ID: mdl-39412082

ABSTRACT

Developing strategies to systematically increase the critical current, the threshold current below which the superconductivity exists, is an important goal of materials science. Here, the concept of quantum phase transition is employed to enhance the critical current of a kagome superconductor CsV3Sb5, which exhibits a charge density wave (CDW) and superconductivity that are both affected by hydrostatic pressure. As the CDW phase is rapidly suppressed under pressure, a large enhancement in the self-field critical current (Ic, sf) is recorded. The observation of a peak-like enhancement of Ic, sf at the zero-temperature limit (Ic, sf(0)) centered at p* ≈ 20 kbar, the same pressure where the CDW phase transition vanishes, further provides strong evidence of a zero-temperature quantum anomaly in this class of pressure-tuned superconductor. Such a peak in Ic, sf(0) resembles the findings in other well-established quantum-critical superconductors, hinting at the presence of enhanced quantum fluctuations associated with the CDW phase in CsV3Sb5.

16.
IUCrdata ; 9(Pt 9): x240890, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39371666

ABSTRACT

The phase with composition Ti4Fe2C0.82O0.18, tetra-titanium diiron carbide oxide, was unexpectedly synthesized by high-pressure sinter-ing (HPS) of a stoichiometric mixture with nominal composition Ti2Fe. The Ti4Fe2C0.82O0.18 phase crystallizes in the Fd m space group and can be considered as the Ti2Fe structure filled with C and O atoms co-occupying the same octa-hedral void [occupancy ratio 0.82 (7):0.18 (7)]. The Ti4Fe2C0.82O0.18 phase is isotypic with Ti4Ni2C and Ti4Fe2O0.407, and is the first example where C and O atoms co-occupy the same site in filled Ti2Fe structures.

17.
Small ; : e2405521, 2024 Sep 30.
Article in English | MEDLINE | ID: mdl-39350439

ABSTRACT

Diamond exhibits nontrivial hardness and abrasion, ultra-high thermal conductivity, and light transmission over a wide wavelength range. All these properties are anisotropic. There is considerable literature on the synthesis of large-sized monocrystalline diamonds but the synthesis of highly oriented monocrystalline diamonds is limited. Here, [100] oriented monocrystalline needle-like diamonds are successfully synthesized with an aspect ratio of up to 14 by controlling the temperature gradient and carbon concentration gradient using FeCo alloy as the catalyst at ≈5.8 GPa and 1473 K. The distinctive morphology and microstructure of needle-like diamonds are characterized using Scanning Electron Microscopy, X-ray diffraction, and Focused Ion Beam-Transmission Electron Microscopy. A four-stage growth model is established to elucidate the growth mechanism along the [100], which sheds light on the synthesis of diamonds with predetermines crystal orientations. Increasing the aspect ratio of needle-like diamonds further may enable the development of diamond fibers and assist in the fabrication of laser diamonds with specific orientation requirements.

18.
Int J Biol Macromol ; 281(Pt 1): 136150, 2024 Oct 05.
Article in English | MEDLINE | ID: mdl-39369493

ABSTRACT

Polyphenol complexes can improve the physicochemical and functional properties of starch. In this study, a wheat starch-Lonicera caerulea berry polyphenol complex (WS-LCBP) was prepared using dynamic high-pressure microfluidization (DHPM). The effects of different DHPM pressures (150 and 250 MPa), number of cycles (1 and 3), and LCBP content (0 %, 6 %, 8 %, and 10 %) on the multiscale structure, physicochemical properties, and in vitro digestibility of WS-LCBP were examined. After a single 250 MPa DHPM cycle, Average particle size and water separation rate of WS were reduced by 42.40 % and 16.67 %, the freeze-thaw stability was significantly improved (P < 0.05), and the resistant starch (RS) content 68.67 % was significantly increased (P < 0.05). WS-LCBP has a V-shaped starch structure, which hinders gelatinization and increases enthalpy. The RS content of the WS-LCBP ranged from 72.46 % to 89.09 %, which was significantly higher (P < 0.05) than that of wheat starch subjected to a single 150 MPa DHPM cycle (36.31 %). Three 250 MPa DHPM cycles were beneficial for the formation of WS-LCBP. However, excessive DHPM treatment pressure and frequency reduced the recombination rate of LCBP and wheat starch. This study provides reference data for the industrial production of nutritionally functional wheat-resistant starch using green technologies.

19.
ChemSusChem ; : e202401694, 2024 Oct 06.
Article in English | MEDLINE | ID: mdl-39370406

ABSTRACT

Hydrogen has received enormous attention as a clean fuel with its high specific energy (142 MJ/kg). To apply hydrogen as a practically available energy vector, the direct production of high-pressure hydrogen with high purity is pivotal, as it allows for circumventing the mechanical compression process. Recently, the concept of utilizing sodium borohydride (SBH) dehydrogenation as a chemical compressor that can generate high-pressure hydrogen gas was demonstrated by adopting formic acid as an acid catalyst. However, the presence of impurities (e.g., CO, CO2) in the final gas product requires an alternative method to enhance the use of SBH as a chemical compressor. Here, we highlighted the feasibility of producing high-purity, high-pressure hydrogen gas from the SBH dehydrogenation with and without Co-based catalysts. The scrutiny behind the thermodynamics and kinetics of the SBH dehydrogenation was conducted under the elevated pressure condition. As a result, the dual roles of the catalysts as proton collectors and heat sources were revealed, both of which are essential for improving hydrogen production efficiency. We hope that our research stimulates subsequent research that pave the way to exploit hydrogen as an energy vector and achieve a more sustainable future society.

20.
Food Chem ; 463(Pt 3): 141402, 2024 Sep 23.
Article in English | MEDLINE | ID: mdl-39332366

ABSTRACT

Fruit derivatives are commonly obtained by applying processing operations deemed responsible for the loss of phenol compounds, but very little information is available on the fate of phenols upon digestion of these products. The present study evaluated the effect of thermal and mechanical treatments, commonly applied to turn apple pulp into puree and homogenate, on phenolic bioaccessibility and antioxidant activity. Despite a 20 % decrease in polyphenols due to processing, their bioaccessibility was higher in apple derivatives (>20 %) compared to pulp (∼2 %). Polyphenol oxidase (PPO), inactivated by thermal treatments in apple derivatives but not in the pulp, was hypothesized to be responsible for this difference. Results acquired on an unprocessed PPO-free apple model, only featuring quercetin-3-glucoside and pectin, actually exhibited similar bioaccessibility as processed derivatives. The radical scavenging capacity was unaffected by the structural integrity of apples, indicating independence from the plant tissue's hierarchical arrangement. After digestion, radical scavenging capacity decreased in the real apple matrices, correlating with phenolic content, while it was retained in the apple model, further suggesting the pivotal food matrix role in modulating polyphenols bioaccessibility and subsequent biological activity. Translating these results to an industrial scale, processing conditions can be optimized not only to guarantee that the quality requirements are met, but also to achieve desired nutritional benefits.

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