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1.
Mikrochim Acta ; 189(10): 384, 2022 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-36125580

RESUMEN

A new iron porphyrin-based organic polymer (Fe-POP) was synthesized through the William ether reaction. The as-prepared Fe-POP presented high chemical stability, wide pore distribution, high iron content, and strong affinity with 3,3',5,5'-tetramethylbenzidine (TMB) and hydrogen peroxide (H2O2), which contributed to its excellent peroxidase-mimicking performance. In the presence of H2O2, Fe-POP could catalyze the transparent TMB into blue ox-TMB, which could be easily distinguished by the naked eyes. Moreover, glutathione (GSH) and ascorbic acid (AA) could convert blue ox-TMB into colorless TMB due to the inhibitory effect of GSH/AA to the catalytic oxidation of TMB. Based on this phenomenon, a rapid and sensitive colorimetric method for the assay of H2O2, GSH, and AA was developed using Fe-POP as sensor. The detection limits of H2O2, GSH, and AA  were 1.37, 0.44, and 0.33 µM, respectively. Finally, the colorimetric method based on Fe-POP was used to evaluate the GSH and AA content in real samples, which provided the guidance for GSH and AA supplements in our daily diet, suggesting the significant potential of Fe-POP in practical applications.


Asunto(s)
Colorimetría , Porfirinas , Ácido Ascórbico/química , Bencidinas , Colorimetría/métodos , Colorantes/química , Éteres , Glutatión/química , Peróxido de Hidrógeno/química , Hierro , Oxidorreductasas , Peroxidasa , Peroxidasas/química , Polímeros , Porosidad , Porfirinas/química
2.
Sci Rep ; 12(1): 15544, 2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-36109611

RESUMEN

Although several studies have analyzed inter-individual differences in the femoral neck cortical microstructure, intra-individual variations have not been comprehensively evaluated. By using microCT, we mapped cortical pore volume fraction (Ct.Po) and thickness (Ct.Th) along the superolateral femoral neck in 14 older women (age: 77.1 ± 9.8 years) to identify subregions and segments with high porosity and/or low thickness-potential "critical" spots where a fracture could start. We showed that Ct.Po and Ct.Th significantly differed between basicervical, midcervical, and subcapital subregions of the femoral neck (p < 0.001), where the subcapital subregion showed the lowest mean Ct.Th and the highest mean Ct.Po. These cortical parameters also varied substantially with age and with the location of the analyzed microsegments along the individual's neck (p < 0.001), showing multiple microsegments with high porosity and/or low thickness. Although the highest ratio of these microsegments was found in the subcapital subregion, they were also present at other examined subregions, which may provide an anatomical basis for explaining the fracture initiation at various sites of the superolateral neck. Given that fractures likely start at structurally and mechanically weaker spots, intra-individual variability in Ct.Po and Ct.Th should be considered and the average values for the entire femoral neck should be interpreted with caution.


Asunto(s)
Cuello Femoral , Fracturas Óseas , Anciano , Anciano de 80 o más Años , Femenino , Fémur , Cuello Femoral/diagnóstico por imagen , Humanos , Porosidad , Microtomografía por Rayos X
3.
J Hazard Mater ; 439: 129676, 2022 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-36104904

RESUMEN

Enzyme membrane systems (EMS) have generated considerable interest because of their advantages of accelerating reactions, eliminating product inhibition, and enhancing conversion rates. However, there are deficiencies in the efficient fabrication of affinity carrier membranes and dynamic catalytic separation properties. Herein, a strong and highly flexible spunlaced viscose/bacterial cellulose (BC) composite membrane in situ embedded with graphene oxide (GO) was developed by combining a scalable bio-synthesis method with atom transfer radical polymerization technology. Notably, the layer-by-layer growth of BC on composite film and the addition of GO resulted in an entangled network with strong hydrogen bonding, endowing the resulting membrane with superior mechanical properties and flexibility, while facilitating a gradient structure and porous transport channels. Subsequently, a novel and highly efficient EMS was constructed by using abundant molecular brushes on composite membrane as immobilized enzyme carrier. The resulting EMS exhibited a high throughput (2.17 L/min*m2) and an interception rate (98.64%) in dynamic catalytic sulfonamide antibiotic wastewater activated with syringaldehyde mediator. Meanwhile, the removal rates of sulphapyridine and sulfamethazine were 97.20% and 94.78% under 0.14 MPa and 15 min, respectively. This efficient and scalable manufacturing strategy is of great significance and may pave a novel pathway for antibiotics wastewater treatment and recycling.


Asunto(s)
Antibacterianos , Celulosa , Antibacterianos/farmacología , Bacterias , Celulosa/química , Grafito , Porosidad , Sulfanilamida , Sulfonamidas
4.
J Hazard Mater ; 439: 129659, 2022 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-36104923

RESUMEN

Three isomeric metal-organic frameworks (MOFs) such as MAF-5, - 6, and - 32 (with the same composition of [Zn(2-ethylimidazole)2]) were carbonized and, for the first time, activated further with KOH to prepare highly porous MOF-derived carbons (MDCs). Importantly, MDC-32 derived from non-porous MAF-32 had the highest porosity among the three MDCs although it has the lowest porosity when no KOH activation was done. Adsorption of sulfanilamide and chloroxylenol from water was investigated with the MDCs. Among the MDCs, MDC-32 showed the best adsorptive performance for sulfanilamide and chloroxylenol. Moreover, MDC-32, had the highest adsorption capacity (256 mg/g) for removing sulfanilamide from water, compared with any adsorbent reported so far. Based on the observed adsorption and properties of the adsorbate and adsorbent, π-π and hydrogen bonding interactions, with a slight contribution of repulsive electrostatic interaction, could be suggested as the mechanism for the sulfanilamide adsorption over the MDC-32. Moreover, the MDC-32 could be recycled easily for up to four cycles. It could be suggested that non-porous MOFs can be a good precursor for highly porous MDCs, if activated well using KOH, for example. Finally, MAF-32-derived carbon, MDC-32, might be suggested as a plausible adsorbent to eliminate organics such as sulfanilamide from water.


Asunto(s)
Estructuras Metalorgánicas , Adsorción , Carbono , Porosidad , Sulfanilamida , Agua , Xilenos
5.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 36(9): 1126-1131, 2022 Sep 15.
Artículo en Chino | MEDLINE | ID: mdl-36111476

RESUMEN

Objective: To compare the effectiveness between three-dimensional (3D) printed porous titanium alloy cage (3D Cage) and poly-ether-ether-ketone cage (PEEK Cage) in the posterior lumbar interbody fusion (PLIF). Methods: A total of 66 patients who were scheduled to undergo PLIF between January 2018 and June 2019 were selected as the research subjects, and were divided into the trial group (implantation of 3D Cage, n=33) and the control group (implantation of PEEK Cage, n=33) according to the random number table method. Among them, 1 case in the trial group did not complete the follow-up exclusion study, and finally 32 cases in the trial group and 33 cases in the control group were included in the statistical analysis. There was no significant difference in gender, age, etiology, disease duration, surgical segment, and preoperative Japanese Orthopaedic Association (JOA) score between the two groups (P>0.05). The operation time, intraoperative blood loss, complications, JOA score, intervertebral height loss, and interbody fusion were recorded and compared between the two groups. Results: The operations of two groups were completed successfully. There was 1 case of dural rupture complicated with cerebrospinal fluid leakage during operation in the trial group, and no complication occurred in the other patients of the two groups. All incisions healed by first intention. There was no significant difference in operation time and intraoperative blood loss between groups (P>0.05). All patients were followed up 12-24 months (mean, 16.7 months). The JOA scores at 1 year after operation in both groups significantly improved when compared with those before operation (P<0.05); there was no significant difference between groups (P>0.05) in the difference between pre- and post-operation and the improvement rate of JOA score at 1 year after operation. X-ray film reexamination showed that there was no screw loosening, screw rod fracture, Cage collapse, or immune rejection in the two groups during follow-up. At 3 months and 1 year after operation, the rate of intervertebral height loss was significantly lower in the trial group than in the control group (P<0.05). At 3 and 6 months after operation, the interbody fusion rating of trial group was significantly better in the trial group than in the control group (P<0.05); and at 1 year after operation, there was no significant difference between groups (P>0.05). Conclusion: There is no significant difference between 3D Cage and PEEK Cage in PLIF, in terms of operation time, intraoperative blood loss, complications, postoperative neurological recovery, and final intervertebral fusion. But the former can effectively reduce vertebral body subsidence and accelerate intervertebral fusion.


Asunto(s)
Cetonas , Fusión Vertebral , Aleaciones , Benzofenonas , Pérdida de Sangre Quirúrgica , Tornillos Óseos , Éter , Éteres , Éteres de Etila , Humanos , Vértebras Lumbares/cirugía , Polímeros , Porosidad , Fusión Vertebral/métodos , Titanio , Resultado del Tratamiento
6.
Food Res Int ; 160: 111710, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36076406

RESUMEN

Shrinkage and collapse phenomena are the two mechanisms involved in the evolution of pores within food products during dehydration. These phenomena can be mathematically represented by shrinkage and collapse functions, which can be derived from theoretical models of porosity, bulk density, or volume reduction coefficient. In this contribution, these two functions were simplified to capture four extreme scenarios of dehydration, which consist in the combination of total or no shrinkage with total or no collapse. The four simplified equations were used to generate theoretical maps characterized by three distinct zones that are associated with pore evolution. Each of these zones represents a key dehydration situation. By superimposing experimental data of porosity, bulk density, or volume reduction coefficient on these theoretical maps, it is possible to assess dehydration processes, i.e., drying technologies and/or dehydration conditions, in terms of pore formation and evolution over time. These theoretical maps can be constructed for each food product before starting the dehydration processes. Therefore, when the experimental data is available, the suggested mapping approach is a simple, fast, and reliable tool to: (i) assess the performance of a given dehydration process versus specific cases of pore formation, and (ii) compare different dehydration processes in terms of their ability to promote pore formation. This practical tool can be used by the industry and academia to quantitatively evaluate how far a drying technology and/or its dehydration conditions are from the ideal scenario in terms of pore formation. This gap quantification will provide a basis for converging towards the ideal scenario by fine-tuning the dehydration conditions or choosing the appropriate drying technology.


Asunto(s)
Deshidratación , Desecación , Humanos , Modelos Teóricos , Porosidad
7.
J Am Chem Soc ; 144(37): 16755-16760, 2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-36085555

RESUMEN

The toxicity, corrosiveness, and volatility of elemental bromine presents challenges for its safe storage and transportation. Purification from other halogens is also difficult. Here, we report an easy-to-prepare calix[4]pyrrole-based azo-bridged porous organic polymer (C4P-POP) that supports efficient bromine capture. C4P-POP was found to capture bromine as a vapor and from a cyclohexane source phase with maximum uptake capacities of 3.6 and 3.4 g·g-1, respectively. Flow-through adsorption experiments revealed that C4P-POP removes 80% of the bromine from a 4.0 mM cyclohexane solution at a flow rate of 45 mL·h-1. C4P-POP also allowed the selective capture of bromine from a 1:1 mixture of bromine and iodine in cyclohexane.


Asunto(s)
Bromo , Yodo , Ciclohexanos , Halógenos , Polímeros , Porosidad , Pirroles
8.
ACS Appl Mater Interfaces ; 14(37): 41764-41778, 2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-36087275

RESUMEN

3D-printed porous tantalum scaffold has been increasingly used in arthroplasty due to its bone-matching elastic modulus and good osteoinductive ability. However, the lack of antibacterial ability makes it difficult for tantalum to prevent the occurrence and development of periprosthetic joint infection. The difficulty and high cost of curing periprosthetic joint infection (PJI) and revision surgery limit the further clinical application of tantalum. Therefore, we fabricated vancomycin-loaded porous tantalum scaffolds by combining the chemical grafting of (3-aminopropyl)triethoxysilane (APTES) and the electrostatic assembly of carboxymethyl chitosan and vancomycin for the first time. Our in vitro experiments show that the scaffold achieves rapid killing of initially adherent bacteria and effectively prevents biofilm formation. In addition, our modification preserves the original excellent structure and biocompatibility of porous tantalum and promotes the generation of mineralized matrix and osteogenesis-related gene expression by mesenchymal stem cells on the surface of scaffolds. Through a rat subcutaneous infection model, the composite bioscaffold shows efficient bacterial clearance and inflammation control in soft tissue and creates an immune microenvironment suitable for tissue repair at an early stage. Combined with the economic friendliness and practicality of its preparation, this scaffold has great clinical application potential in the treatment of periprosthetic joint infection.


Asunto(s)
Quitosano , Infecciones Relacionadas con Prótesis , Animales , Antibacterianos/farmacología , Biopelículas , Quitosano/farmacología , Osteogénesis , Porosidad , Impresión Tridimensional , Ratas , Tantalio/farmacología , Andamios del Tejido/química , Vancomicina/farmacología
9.
Biosens Bioelectron ; 216: 114659, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36095979

RESUMEN

Pesticide residues have raised serious public concern towards agriculture, environment and food safety. Recently, metal-organic frameworks (MOFs) have been employed as promising recognition and signal generation elements in sensors for pesticide detection. However, the general format of tiny particles with poor dispersity brings obstacles to detection operation and the improvement of sensing performance. Here, we report a sensor based on porous MOFs hybrid sponge for fluorescent-visible detection of methyl parathion. Benefiting from the intermediate of adhesive and porous fibrin film, MOFs are loaded with good dispersion and accessibility, thereby endowing the sensor with a rapid response time of 10-min, a wide linear detection range of 50-2500 µg L-1, and a low limit of detection of 4.95 µg L-1. Moreover, the hybrid sensor presented superior durability and anti-interference ability to the detection in complex conditions, including organic solvents, acidic solution, high temperature, and even chemical interferences. This hybrid not only provides a new construction strategy for a nanomaterial-based sensor, but also permits a portable and durable route for the detection.


Asunto(s)
Técnicas Biosensibles , Estructuras Metalorgánicas , Metil Paratión , Residuos de Plaguicidas , Plaguicidas , Fibrina , Estructuras Metalorgánicas/química , Compuestos Organofosforados , Porosidad , Solventes
10.
Anal Chim Acta ; 1228: 340309, 2022 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-36127007

RESUMEN

In this study, cetyltrimethylammonium bromide and zeolitic imidazolate framework-8 (ZIF-8) were first assembled via the chemical co-precipitation, and high-quality carbon-based metal-free nanomaterials were synthesized using a heat-treatment process. The internal and morphological characteristics of hexagonal Star ZIF-8 were investigated using scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The electrochemical sensor with a good response to Cd(II) was prepared via square-wave anodic stripping voltammetry (SWASV) with Star ZIF-8 nanomaterial-modified glassy carbon electrodes. The main parameters were adjusted to obtain the optimal stripping response and a wide linear range. Concurrently, under the calculation of SWASV, the sensitivity of Star ZIF-8-Nafion/GCE to Cd(II) was increased by five orders of magnitude (0.5-230 µg/L), and the determination level was even low to 0.48 µg/L. Based on the high anti-interference ability and stability of the sensor, the application potential of Star ZIF-8 carbon-based metal-free nanomaterials for the detection of trace Cd(II) in was confirmed.


Asunto(s)
Estructuras Metalorgánicas , Zeolitas , Cadmio/química , Carbono/química , Cetrimonio , Estructuras Metalorgánicas/química , Nitrógeno , Porosidad , Tabaco , Zeolitas/química
11.
Carbohydr Polym ; 296: 119926, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36087979

RESUMEN

Bamboo cellulose fibers (BCFs) has attracted increasing attention in many fields due to its high mechanical strength and interconnected porous structure. Drying is a key factor that determines the final structure and properties of BCFs. In this work, three kinds of BCFs, i.e., conventional-dried (CD-BCFs), freeze-dried (FD-BCFs), and supercritical CO2-dried (SD-BCFs), were prepared via different drying methods. The effects of drying methods on their supramolecular structure, porosity, and mechanical properties were studied, and the structure-property relationships were proposed. The CD-BCFs composed of well-aligned crystalline nanofibrils with a dense structure exhibited the best mechanical properties (tensile strength of 854.54 MPa). The SD-BCFs featured with interconnected 3D microfibril networks give a highly porous structure and the highest surface area of 9.162 m2/g. The FD-BCFs showed medium mechanical properties and surface area owing to the stacked lamellar microfibril network. This work provides guidelines for designing BCFs with proper structure for various end-use applications.


Asunto(s)
Celulosa , Celulosa/química , Composición de Medicamentos , Liofilización , Porosidad , Resistencia a la Tracción
12.
Anal Chim Acta ; 1227: 340270, 2022 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-36089309

RESUMEN

In this work, a porous capillary monolithic column was simply prepared by in situ thiol-alkyne click polymerization of dipentaerythritol hexakis (3-mercaptopropionate) and dimethyl dipropargylmalonate in fused-silica capillary. The capillary monolithic column shows excellent permeability, high porosity, and thoiether-rich groups, thereby, a high-efficient capacity for trace estrogens from complex samples are obtained via electron-donor-acceptor π-π interaction and hydrophobic interaction. The highest adsorption efficiency for estrogens is achieved at pH = 7.0 with a flow rate of 0.200 mL min-1. The superior adsorption capacities of the as-prepared capillary column for eight estrogens range from 0.092 mg m-1 to 0.31 mg m-1. A simple, reliable, and sensitive method for the determination of eight estrogens in biological and environmental samples is developed using the monolithic polymer as in-tube solid-phase microextraction coupled with ultrahigh performance liquid chromatography-tandem mass spectrometry (SPME-UPLC-MS/MS), and the total instrumental analysis time for the SPME-UPLC-MS/MS procedures was about 60 min per sample. The developed method shows a wide linear range (0.0500-5.00 µg L-1), and low limits of detection (5.34-9.63 ng L-1) for estrogens. The concentrations of estrogens in serum, urine, and pond water samples are found to be no more than 3.69, 0.741, and 1.04 µg L-1, respectively, and the satisfying recoveries for the eight estrogens range from 80.3% to 113% with relative standard deviations (n = 5) of 1.5-9.4%. The established method is highly potential for extraction and analysis of ultratrace target estrogens in complex matrices, such as biological and environmental samples.


Asunto(s)
Estrógenos , Espectrometría de Masas en Tándem , Cromatografía Líquida de Alta Presión/métodos , Cromatografía Liquida/métodos , Estrógenos/análisis , Porosidad
13.
Anal Chim Acta ; 1227: 340301, 2022 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-36089313

RESUMEN

In this work, a ratiometric electrochemical sensor was developed for the detection of perphenazine (PPZ). The sensor was constructed by electrodepositing Cu-coordinated molecularly imprinted polymer (Cu-MIP) on Ag nanoparticles (NPs) modified flexible porous carbon cloth. The Cu-MIP showed highly electrochemical response because of the enhanced adsorptive ability and electronic properties of Cu2+ chelation; Ag NPs could provide a stable and effective reference signal for ratiometric quantification. Thus the resulted sensor not only displayed high selectivity and sensitivity, but also exhibited satisfactory reproducibility and anti-interference ability. Under the optimum conditions, the quantitative detection of PPZ was performed with differential pulse voltammetry. It was found that the peak current ratio of PPZ and Ag NP was linear to the concentration of PPZ in the range of 1-700 nmol L-1 (R2 = 0.9968), and the limit of detection was 0.43 nmol L-1 (S/N = 3). The practicability of the sensor was examined by determining human serum and pharmaceutical samples, and satisfactory results and recoveries (ranging from 92.46% to 104.90%) were achieved.


Asunto(s)
Nanopartículas del Metal , Impresión Molecular , Carbono/química , Técnicas Electroquímicas/métodos , Humanos , Impresión Molecular/métodos , Polímeros Impresos Molecularmente , Perfenazina , Porosidad , Reproducibilidad de los Resultados , Plata
14.
Nat Commun ; 13(1): 5249, 2022 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-36068273

RESUMEN

In vivo surface-enhanced Raman scattering (SERS) imaging allows non-invasive visualization of tumors for intraoperative guidance and clinical diagnostics. However, the in vivo utility of SERS is greatly hampered by the strong optical scattering and autofluorescence background of biological tissues and the lack of highly active plasmonic nanostructures. Herein, we report a class of porous nanostructures comprising a cubic AuAg alloy nanoshell and numerous nanopores. Such porous nanostructures exhibit excellent near-infrared II plasmonic properties tunable in a broad spectral range by varying the pore features while maintaining a small dimension. We demonstrate their exceptional near-infrared II SERS performance varying with the porous properties. Additionally, near-infrared II SERS probes created with porous cubic AuAg nanoshells are demonstrated with remarkable capability for in vivo visualization of sub-millimeter microtumors in a living mouse model. Our near-infrared II SERS probes hold great potentials for precise demarcation of tumor margins and identification of microscopic tumors.


Asunto(s)
Nanoporos , Nanocáscaras , Neoplasias , Animales , Oro/química , Ratones , Nanocáscaras/química , Neoplasias/diagnóstico por imagen , Porosidad , Espectrometría Raman/métodos
15.
J Synchrotron Radiat ; 29(Pt 5): 1232-1240, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-36073882

RESUMEN

New developments at synchrotron beamlines and the ongoing upgrades of synchrotron facilities allow the possibility to study complex structures with a much better spatial and temporal resolution than ever before. However, the downside is that the data collected are also significantly larger (more than several terabytes) than ever before, and post-processing and analyzing these data is very challenging to perform manually. This issue can be solved by employing automated methods such as machine learning, which show significantly improved performance in data processing and image segmentation than manual methods. In this work, a 3D U-net deep convolutional neural network (DCNN) model with four layers and base-8 characteristic features has been developed to segment precipitates and porosities in synchrotron transmission X-ray micrograms. Transmission X-ray microscopy experiments were conducted on micropillars prepared from additively manufactured 316L steel to evaluate precipitate information. After training the 3D U-net DCNN model, it was used on unseen data and the prediction was compared with manual segmentation. A good agreement was found between both segmentations. An ablation study was performed and revealed that the proposed model showed better statistics than other models with lower numbers of layers and/or characteristic features. The proposed model is able to segment several hundreds of gigabytes of data in a few minutes and could be applied to other materials and tomography techniques. The code and the fitted weights are made available with this paper for any interested researcher to use for their needs (https://github.com/manasvupadhyay/erc-gamma-3D-DCNN).


Asunto(s)
Imagenología Tridimensional , Sincrotrones , Imagenología Tridimensional/métodos , Redes Neurales de la Computación , Porosidad , Tomografía , Rayos X
16.
J Mater Sci Mater Med ; 33(9): 64, 2022 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-36104513

RESUMEN

The repair of critical diaphyseal defects of lower weight-bearing limbs is an intractable problem in clinical practice. From December 2017, we prospectively applied 3D printed porous Ti6Al4V scaffolds to reconstruct this kind of bone defect. All patients experienced a two-stage surgical process, including thorough debridement and scaffold implantation. With an average follow-up of 23.0 months, ten patients with 11 parts of bone defects were enrolled in this study. The case series included three females and seven males, their defect reasons included seven parts of osteomyelitis and four parts of aseptic nonunion. The bone defects located at femur (five parts) and tibia (six parts), with an average defect distance of 12.2 cm. Serial postoperative radiologic follow-ups displayed a continuous process of new bone growing and remodeling around the scaffold. One patient suffered tibial varus deformity, and he underwent a revision surgery. The other nine patients achieved scaffold stability. No scaffold breakage occurred. In conclusion, the implantation of 3D printed Ti6Al4V scaffold was feasible and effective to reconstruct critical bone defects of lower limbs without additional bone grafting. Graphical abstract.


Asunto(s)
Trasplante Óseo , Andamios del Tejido , Aleaciones , Femenino , Humanos , Extremidad Inferior , Masculino , Porosidad , Impresión Tridimensional , Estudios Prospectivos , Titanio
17.
Sci Rep ; 12(1): 15405, 2022 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-36100638

RESUMEN

Parameters such as gas content (GAS), porosity (PHI) and total organic carbon (TOC) are key parameters that reveal the shale gas geological "sweet spot" of reservoirs. However, the lack of a three-dimensional high-precision prediction method is not conducive to large-scale exploration of shale gas. Although the parameter prediction accuracy based on well logging data is relatively high, it is only a single point longitudinal feature. On the basis of prestack inversion of reservoir information such as P-wave velocity and density, high-precision and large-scale "sweet spot" spatial distribution predictions can be realized. Based on the fast growing and widely used deep learning methods, a one-dimensional convolutional neural network (1D-CNN) "sweet spot" parameter prediction method is proposed in this paper. First, intersection analysis is carried out for various well logging information to determine the sensitive parameters of geological "sweet spot". We propose a new standardized preprocessing method based on the characteristics of the well logging data. Then, a 1D-CNN framework is designed, which can meet the parameter prediction of both depth-domain well logging data and time-domain seismic data. Third, well logging data is used to train a high-precision and robust geological "sweet spot" prediction model. Finally, this method was applied to the WeiRong shale gas field in Sichuan Basin to achieve a high-precision prediction of geological "sweet spots" in the Wufeng-Longmaxi shale reservoir.


Asunto(s)
Gas Natural , Redes Neurales de la Computación , Geología , Yacimiento de Petróleo y Gas , Porosidad
18.
ACS Macro Lett ; 11(9): 1142-1147, 2022 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-36048420

RESUMEN

Ultrafiltration (UF) membranes, particularly membranes fabricated from self-assembled diblock copolymers, hold promise in wastewater treatment, dairy, and food industries. Membrane development goals involve combining a highly porous selective layer with a narrow pore size distribution with a mechanically stable supporting layer to achieve constant flux. To date, isoporous integral asymmetric membranes have been formed either as flat sheets or hollow fibers, and a surface-selective layer determines membrane separation performance. A unique isoporous membrane of the poly(4-vinylbenzocyclobutene)-b-poly(4-vinylpyridine) (PVBCB-b-P4VP) diblock copolymer with a substructure of almost homogeneous porosity throughout the body of the material (three-dimensional porosity) has been developed. Moreover, the matrix of the membrane (PVCB) enables it to undergo cross-linking, allowing the membrane to be thermally sterilized and applied in high-temperature UF applications.


Asunto(s)
Polímeros , Ultrafiltración , Membranas Artificiales , Polímeros/química , Porosidad , Ultrafiltración/métodos
19.
Phys Chem Chem Phys ; 24(36): 21853-21862, 2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-36065762

RESUMEN

Due to their unique self-assembly properties, ionic liquids (ILs) are versatile soft templates for the formation of mesoporous materials. Here, we report the use of ionic liquids as soft templates for the straightforward formation of mesoporous ionosilica phases. Ionosilicas are highly polyvalent functional materials that are constituted of ionic building blocks that are covalently immobilized within a silica hybrid matrix. Ionosilicas have attracted significant interest in the last few years due to their high potential for applications in water treatment and upgrading, separation and drug delivery. The straightforward and reproducible formation of mesoporous ionosilica phases is therefore highly desirable. In this context, we report the formation of mesoporous ionosilica phases via non-hydrolytic sol-gel procedures in the presence of ionic liquids. Ionic liquids appear as particularly versatile templates for mesoporous ionosilicas due to their high chemical similarity and affinity between ILs and silylated ionic precursors. We therefore studied the textures of the resulting ionosilica phases, after IL elimination, using nitrogen sorption, small angle X-ray scattering (SAXS) and transmission and scanning electron microscopies. All these techniques give concordant results and show that the textures of ionosilica scaffolds in terms of specific surface area, pore size, pore size distribution and connectivity can be efficiently controlled by the nature and the quantity of the ionic liquid that is used in the ionothermal sol-gel procedure.


Asunto(s)
Líquidos Iónicos , Líquidos Iónicos/química , Nitrógeno , Porosidad , Dispersión del Ángulo Pequeño , Dióxido de Silicio/química , Difracción de Rayos X
20.
J Chromatogr A ; 1681: 463461, 2022 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-36108352

RESUMEN

How to improve the performance of chromatographic media is very important in chromatography. Uniform agarose microspheres were successfully prepared using membrane emulsification method with a controllable particle size, followed by multi-step crosslinking and dextran-grafting, respectively. To obtain both fine pore structure and good pressure-resistant property, the effects of both dextran-grafting and crosslinking process were studied carefully and also, the preparation conditions were delicately adjusted. Inverse size-exclusion chromatography was used for determining the pore structure of these agarose microspheres. Uniform agarose microspheres with an average particle size of about 8 µm were obtained with regularly spherical, transparent and smooth appearance. By introducing a certain molecular weight of dextran or pentaerythritol glycidyl ether at different crosslinking steps, both the pressure-resistant and the chromatographic properties of microspheres were improved. Both the maximum flow velocity and the corresponding pressure drop increased with the decrease of the molecular weight of dextran, i.e., 99 cm/h and 3.22 MPa, respectively, using dextran T3 (3 kDa). The average pore size of agarose microspheres decreased from 6.04±0.56 nm to 2.50±0.12 nm with the increase of the molecular weight of dextran from dextran T3 (3 kDa) to dextran T100 (100 kDa), with a high resolution obtained for a certain molecular range of model proteins. Also, the pressure-resistant property was highly improved in multi-step crosslinking process, with a maximum flow velocity of 107 cm/h and a corresponding pressure drop of 3.62 MPa obtained after the whole crosslinking steps. The average pore size of agarose microspheres was 3.72±0.32, 3.90±0.21 and 3.60±0.27 nm for the introduction of pentaerythritol glycidyl ether as the crosslinking agent at different steps, respectively. These uniform dextran-grafted agarose microspheres have a finely controllable molecular range with a high resolution compared with traditional ones, which are beneficial for chromatographic selectivity. Therefore, they are very useful for high-resolution chromatography and have wide applications in downstream process.


Asunto(s)
Dextranos , Cromatografía en Gel , Dextranos/química , Compuestos Epoxi , Microesferas , Tamaño de la Partícula , Porosidad , Glicoles de Propileno , Sefarosa/química
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