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1.
Comput Biol Med ; 171: 108142, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38394805

RESUMEN

As the alternative solution to the conventional guidewire, the magnetic robot can help interventionists perform percutaneous coronary intervention (PCI) because magnetic fields are transparent and safe for biological tissues. Despite extensive research on magnetic robots, the exploration of their deflection control for practical applications still requires further research. In this paper, a hierarchical analysis framework (HAF) is proposed to control the magnetic robot's deflection. Six deflection subpatterns are analyzed through HAF, incorporating statistical and regression analyses to establish governing equations of magnetic robots. The performance of the control equations is validated through precise control of the magnetic continuum robot (MCR) and magnet-tipped robot (MTR) in both uniform and gradient magnetic fields. Experimental results show that under the uniform magnetic field, the average root mean square error (RMSE) of governing equation of MCR is 0.08±0.05°, 0.41±0.34°, 1.47±0.49° and 1.07±0.66° for four-types horizontal deflection, 0.19±0.07mm and 0.16±0.10mm for two-types vertical deflection, respectively. Based on the governing equations, the MTR is able to precisely navigate to coronary arteries with various degrees of stenosis (30%, 52%, and 60%), and successfully pass through a series of rings, with an average error of 1.05 mm. The research successfully demonstrates the potential of HAF in creating robust and reliable governing equations for magnetic actuation in medical robotics, with significant implications for enhancing the precision and safety of PCI procedures.


Asunto(s)
Intervención Coronaria Percutánea , Robótica , Robótica/métodos , Campos Magnéticos , Imanes , Diseño de Equipo
2.
Artículo en Inglés | MEDLINE | ID: mdl-37347332

RESUMEN

The precise and exhaustive discernment of factors influencing CO2 emissions underpins the advancement toward sustainable, low-carbon development. Although numerous studies have probed the correlation between predetermined proxy variables and carbon emissions, methodological constraints have often led to an inability to effectively discern carbon emission determinants among numerous potential variables or unravel complex, non-linear relationships, and interaction effects. To redress these research gaps, this research utilized machine learning models to correlate urban CO2 emissions with socioeconomic indicators. The model outputs were then visualized and interpreted using explainable methods. The findings indicated that the model successfully identified a comprehensive array of dominant influences on urban CO2 emissions, principally associated with local fiscal policies, land use, energy consumption, industrial development, and urban transportation. The findings further revealed a complex non-linear association between these factors and urban CO2 emissions; however, the majority of these variables displayed a prevalent propensity to intensify carbon emissions in correspondence with an increase in sample value. Additionally, these factors exhibited a complex interactive influence on urban CO2 emissions, with distinct pairings producing a suppressive effect exclusively at specific combination of sample values. Consequently, this research posited that a robust correlation between urban socioeconomic development and CO2 emissions in China remains to be established. Given the varied impacts of these influencing factors across different cities, a differentiated approach to development should be adopted when charting low-carbon trajectories.

3.
Comput Methods Programs Biomed ; 240: 107646, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37320941

RESUMEN

BACKGROUND AND OBJECTIVE: Magnetic guidewire, fabricated from hard-magnetic soft composites, has recently emerged as an appropriate candidate for magnetic actuation systems to perform intravascular surgical navigation, owing to its elastic, magnetically steerable properties and good interphase with biological tissues. A suitable and efficient mathematical model for the magnetic guidewire is essential in the system to execute remote manipulation and active control. METHODS: This paper presents a real-time Kirchhoff rod-based dynamical modeling approach, the magneto-elastic rod model, to simulate magnetic guidewire, which provides accurate simulations for two- and three-dimensional dynamic deflections induced by external magnetic fields and obtains deformed guidewire shapes in quasi-static status. RESULTS: The proposed model is capable of describing the intrinsic principles of elastic body actuation by torques generated from the hard-magnetic soft matrix. The effectiveness of the developed model is validated, and the real-time simulation application is conducted via the semi-implicit numerical integration method. CONCLUSIONS: It has been shown that the presented dynamical model captures large nonlinear deformations and transient responses of the magnetic guidewire in an imitated human blood environment, which could offer robust support for the construction of a simulated magnetically driven surgical system.


Asunto(s)
Cateterismo , Modelos Teóricos , Humanos , Simulación por Computador , Cateterismo/métodos , Fenómenos Físicos , Fenómenos Magnéticos
4.
J Matern Fetal Neonatal Med ; 36(1): 2179383, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37121901

RESUMEN

BACKGROUND: Epidural analgesia (EA) increases the risks of maternal fever during labor, which is associated with adverse maternal and neonatal outcomes, while the risk factors for epidural-associated fever and strategies for minimizing these effects remain limited. METHODS: A total of 325 pregnant women were retrospectively analyzed who had attended our hospital for a vaginal in-hospital delivery, including 208 who voluntarily accepted EA and 117 who did not receive EA. During labor, 208 EA women were allocated to a fever group (n = 42, a tympanic temperature ≥37.5 °C during labor), and a no fever group (n = 166). The outcome measures included main maternal and neonatal outcomes, labor times, duration of EA and the total EA dosage administered. RESULTS: 42 out of 208 women given EA exhibited fever temperatures during labor, which were higher than in women who did not receive EA (20.19% vs. 0.85%). Maternal fever had an increased risks for conversion to surgery (adjusted odds ratio (AOR), 4.05; 95% CI, 1.44-11.39) and neonatal infections (5.13; 1.98-13.29) compared to the no fever group. While maternal fever did not increase the risks for assisted vaginal delivery, fetal distress or admission to the neonatal intensive care unit (NICU), it was predominantly associated with primiparity and lesser times of gravity. Frequent cervical examinations, the duration of first stage and total labor, and the duration of EA and its total dosage were positively correlated with the incidence of fever. Furthermore, after stratifying risk factors into subgroups, we found that more frequent cervical examinations (≥7 times) and longer duration of first stage (≥442.5 min), total labor time (≥490 min), EA (≥610.0 min) increased the risk for epidural-associated fever after adjustment for potential confounding factors. CONCLUSIONS: EA increased the risk of intrapartum epidural-associated fever, which was correlated with adverse perinatal outcomes. Nulliparity, less times of gravidity, ≥7 cervical examinations, increased volume of the EA dosage, prolonged duration of EA and total labor time were risk factors for epidural-associated fever. The findings provide clinicians with insights and strategies to prevent epidural-associated fever more safely and effectively.


Asunto(s)
Analgesia Epidural , Analgesia Obstétrica , Trabajo de Parto , Recién Nacido , Embarazo , Femenino , Humanos , Analgesia Epidural/efectos adversos , Estudios Retrospectivos , Fiebre/epidemiología , Fiebre/etiología , Factores de Riesgo , Analgesia Obstétrica/efectos adversos
5.
Comput Med Imaging Graph ; 106: 102219, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37001423

RESUMEN

The segmentation of true lumen (TL) and false lumen (FL) plays an important role in the diagnosis and treatment of aortic dissection (AD). Although the deep learning methods have achieved remarkable performance for this task, a large number of labeled data are required for training. In order to alleviate the burden of doctors' labeling, in this paper, a novel time-dependent weighted feedback fusion based semi-supervised aortic dissections segmentation framework is proposed by effectively leveraging the unlabeled data. A feedback network is additionally extended to encode the predicted output from the backbone network into high-level feature space, which is then fused with the original feature information of the image to fix previous potential mistakes, thereby segmentation accuracy is improved iteratively. To utilize both labeled data and unlabeled data, the fused feature space flows into the network again to generate the second feedback and make sure consistency with the previous one. The utilization of image feature space provides better robustness and accuracy for the proposed structure. Experiments show that our method outperforms five existing state-of-the-art semi-supervised segmentation methods on both a type-B AD dataset and a public dataset.


Asunto(s)
Disección Aórtica , Humanos , Disección Aórtica/diagnóstico por imagen , Retroalimentación , Procesamiento de Imagen Asistido por Computador , Aprendizaje Automático Supervisado
6.
Probiotics Antimicrob Proteins ; 15(3): 558-572, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-34735679

RESUMEN

The aim of this study is to explore whether or not the combined application of BS15 and H2 is capable to have a more effective control effect on SNE in broilers. A total of 240 1-day-old female chickens were randomly divided into 5 groups: (a) basal diet in negative control group (NC group); (b) basal diet + SNE infection (coccidiosis vaccine + CP) (PC group); (c) basal diet + SNE infection + H2 pre-treatment (BT group); (d) basal diet + SNE infection + BS15 pre-treatment (LT group); and (e) basal diet + SNE infection + H2 pre-treatment + BS15 pre-treatment (MT group). The results showed the MT group had the most positive effect on inhibiting the negative effect of growth performance at 42 days of age. In the detection of the NC, PC, and MT group indicators at 28 days of age, we found that MT group significantly promoted ileum tissue development of broilers, and the ileum of broilers in the MT group formed a flora structure different from NC and PC, although it was found that the MT group had no effect on the butyrate level in the cecum, but it could affect the serum immune level, such as significantly reducing the level of pro-inflammatory cytokine IL-8 and increasing the content of immunoglobulin IgM and IgG. In conclusion, the composite preparation of Lactobacillus johnsonii BS15 and Bacillus licheniformis H2 could effectively improve the growth performance against SNE broilers, which is possibly caused by the improvement of the immune levels, the reduction of inflammation levels, and the promotion of the intestinal development.


Asunto(s)
Enteritis , Enfermedades de las Aves de Corral , Probióticos , Femenino , Animales , Pollos , Probióticos/farmacología , Dieta/veterinaria , Inflamación , Enteritis/veterinaria , Enteritis/prevención & control , Alimentación Animal/análisis , Enfermedades de las Aves de Corral/prevención & control
7.
Cancers (Basel) ; 16(1)2023 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-38201591

RESUMEN

This scoping review evaluated 3D osteosarcoma (OS) models' biomimicry, examining their ability to mimic the tumour microenvironment (TME) and their drug sensitivity. Adhering to PRISMA-ScR guidelines, the systematic search revealed 293 studies, with 70 selected for final analysis. Overall, 64% of 3D OS models were scaffold-based, compared to self-generated spheroid models. Scaffolds generated using native matrix were most common (42%) with collagen I/hydroxyapatite predominating. Both scaffold-based and scaffold-free models were used equally for drug screening. The sensitivity of cancer cells in 3D was reported to be lower than that of cells in 2D in ~90% of the drug screening studies. This correlates with the observed upregulation of drug resistance. OS cells cultured in extracellular matrix (ECM)-mimetic scaffolds and native biomaterials were more resistant than cells in 2D. Co-cultures of OS and stromal cells in 3D models enhanced osteogenic differentiation, ECM remodelling, mineralisation, and angiogenesis, suggesting that tumour-stroma crosstalk promotes disease progression. Seven studies demonstrated selective toxicity of chemotherapeutics towards OS cells while sparing stromal cells, providing useful evidence for developing biomimetic tumour-stroma models to test selective drug toxicity. In conclusion, this review highlights the need to enhance biomimicry in 3D OS models for TME recapitulation, especially in testing novel therapeutics. Future research should explore innovative 3D biomimetic models, biomaterials, and advancements in personalised medicine.

8.
World J Gastroenterol ; 28(40): 5865-5880, 2022 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-36353208

RESUMEN

BACKGROUND: Immune dysfunction is the crucial cause in the pathogenesis of inflammatory bowel disease (IBD), which is mainly related to lymphocytes (T or B cells, incl-uding memory B cells), mast cells, activated neutrophils, and macrophages. As the precursor of B cells, the activation of memory B cells can trigger and differentiate B cells to produce a giant variety of inducible B cells and tolerant B cells, whose dysfunction can easily lead to autoimmune diseases, including IBD. AIM: To investigate whether or not curcumin (Cur) can alleviate experimental colitis by regulating memory B cells and Bcl-6-Syk-BLNK signaling. METHODS: Colitis was induced in mice with a dextran sulphate sodium (DSS) solution in drinking water. Colitis mice were given Cur (100 mg/kg/d) orally for 14 con-secutive days. The colonic weight, colonic length, intestinal weight index, occult blood scores, and histological scores of mice were examined to evaluate the curative effect. The levels of memory B cells in peripheral blood of mice were measured by flow cytometry, and IL-1ß, IL-6, IL-10, IL-7A, and TNF-α expression in colonic tissue homogenates were analyzed by enzyme-linked immunosorbent assay. Western blot was used to measure the expression of Bcl-6, BLNK, Syk, and other signaling pathway related proteins. RESULTS: After Cur treatment for 14 d, the body weight, colonic weight, colonic length, colonic weight index, and colonic pathological injury of mice with colitis were ameliorated. The secretion of IL-1ß, IL-6, TNF-α, and IL-7A was statistically decreased, while the IL-35 and IL-10 levels were considerably increased. Activation of memory B cell subsets in colitis mice was confirmed by a remarkable reduction in the expression of IgM, IgG, IgA, FCRL5, CD103, FasL, PD-1, CD38, and CXCR3 on the surface of CD19+ CD27+ B cells, while the number of CD19+ CD27+ IL-10+ and CD19+ CD27+ Tim-3+ B cells increased significantly. In addition, Cur significantly inhibited the protein levels of Syk, p-Syk, Bcl-6, and CIN85, and increased BLNK and p-BLNK expression in colitis mice. CONCLUSION: Cur could effectively alleviate DSS-induced colitis in mice by regulating memory B cells and the Bcl-6-Syk-BLNK signaling pathway.


Asunto(s)
Colitis , Curcumina , Enfermedades Inflamatorias del Intestino , Animales , Ratones , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Citocinas/metabolismo , Sulfato de Dextran/toxicidad , Modelos Animales de Enfermedad , Interleucina-10 , Interleucina-6 , Células B de Memoria , Ratones Endogámicos C57BL , Transducción de Señal , Factor de Necrosis Tumoral alfa/metabolismo
9.
Front Cell Infect Microbiol ; 12: 907813, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35832382

RESUMEN

The rising incidence of ulcerative colitis has become a new challenge for public health. Chimonanthus nitens Oliv. leaf granule (COG) is a natural medicine used for the treatment of respiratory diseases, which has excellent anti-inflammatory and antioxidant effects. However, the therapeutic effect of COG in ulcerative colitis (UC) has not been reported. Here, the experimental colitis was treated with dextran sodium sulfate (DSS) and COG. After treatment with high (30 g/kg), medium (15 g/kg), and low (7.5 g/kg) doses of COG for 11 consecutive days, the body weight, disease activity index (DAI) score, colon length, colon weight index, and the pathological score of mice were effectively improved. COG significantly reduced the levels of inflammatory cytokines in UC mice in vitro and in vivo and restored the secretion levels of IL-6 and IL-10 in the colon. Meanwhile, compared to mice with colitis, COG-treated mice showed lower levels of MDA, MPO, NO, and eNOS and higher levels of GSH-Px and MAO, which indicated that oxidative stress damage in colitic mice was alleviated by COG. Moreover, less Th17 and more Tregs were observed in the COG-treated groups. In addition, COG improved the diversity and relative abundance of gut microflora in the colon of colitic mice, and Lachnospiraceae_NK4A136_group and Lachnospiraceae_UCG-006 were obviously regulated at the genus level. In summary, COG has a protective effect on DSS-induced experimental colitis, mainly through inhibition of immune-inflammatory responses and oxidative stress and regulation of mTreg cell responses and intestinal flora composition.


Asunto(s)
Colitis Ulcerosa , Colitis , Microbioma Gastrointestinal , Animales , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Colitis/metabolismo , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/tratamiento farmacológico , Colon/patología , Sulfato de Dextran/toxicidad , Modelos Animales de Enfermedad , Ratones , Ratones Endogámicos C57BL , Estrés Oxidativo , Hojas de la Planta , Linfocitos T Reguladores
10.
Artículo en Inglés | MEDLINE | ID: mdl-35388299

RESUMEN

It is known that memory T cells (mT cell) and memory T follicular cells (mTfh) play vital roles in the IBD pathogenesis. Sishen Pill (SSP) is a classic prescription used to treat chronic ulcerative colitis (UC). However, it is still unclear whether SSP can regulate immune homeostasis induced by mT cell and mTfh to treat IBD. In this study, we measured mT cell and mTfh level to explore the conceivable mechanism of SSP-treated IBD. The mice colitis were induced by dextran sulfate sodium (DSS) and were treated by SSP for 7 days. The therapeutic effect of SSP was evaluated by macroscopic and microscopic observation; the mT cell, mTfh, and their subsets were analyzed by flow cytometry. Activation of the JAK/STAT signaling pathway was analyzed by using a Western blot. In the present study, SSP significantly reversed weight loss and colonic injury (colon weight increase and colonic length shortening) caused by 3% DSS in physiological saline solution. Flow cytometry showed that the percentages of CD4+ and CD8+ expressions on central memory T cells were enhanced after SSP treatment, while the CD4+ T cm, CD4+ mTfh (memory T follicular helper) cells and their subpopulations were also significantly increased. Moreover, SSP inhibited the expression of JAK/STAT signaling pathway proteins JAK1, PIAS3, STAT5, p-STAT5, BIM, BAX, caspase-3, and ß-casein and promoted the expression of JAK3, PISA1, Bcl-2, and caveolin-1. In summary, SSP can regulate immune homeostasis induced by mT cell and mTfh in DSS-induced colitis, which is potentially correlated with JAK/STAT signaling pathway activation.

11.
Pharm Res ; 39(6): 1205-1214, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35237921

RESUMEN

PURPOSE: Lipid droplets (LDs) are dynamic organelles which associated with many metabolic processes. Reliable long-term imaging of LD is of great importance in LD-based therapy and research. Conventional fluorescent probes suffer from poor photostability and difficulty of preparation, which compromise their LD imaging ability. In this study, we aim to provide a novel and universal fluorescent probe for LD-specific imaging in both eukaryotic and prokaryotic cells. The versatile and potential applications of the probe were also evaluated. METHODS: We used one-step Suzuki coupling reaction to synthesize a fluoro-pyrazine-bridged donor-acceptor-donor fluorescent probe (T-FP-T). The fluorescent properties and stability of T-FP-T were detected. Then, LD-specific imaging and dynamic movement tracking capabilities of T-FP-T were studied in fungus, bacteria, plant and animal tissues. The biosafety and photodynamic toxicity of the probe under different light irradiation were characterized. RESULTS: T-FP-T showed large Stokes shift, superior brightness, excellent photostability, low toxicity. T-FP-T exhibited significant overlaps with adipophilin antibody or the commercial LD probe (LipidSpot™) in the cytoplasm, but not with Mitotracker red, Lysotracker red and Peroxisome Labeling dye. Moreover, T-FP-T also showed efficient superoxide anion generation capability under white LED light irradiation. The viability of Hela cells co-treated with T-FP-T and 1-h white LED light irradiation decreased to 62%. CONCLUSIONS: All these outstanding capabilities make T-FP-T a new efficient LD-specific imaging probe. The generated superoxide anion from T-FP-T under white LED light irradiation could cause obvious cell death, which will inspire broad study in LD-targeted photodynamic therapy.


Asunto(s)
Colorantes Fluorescentes , Gotas Lipídicas , Animales , Colorantes Fluorescentes/metabolismo , Células HeLa , Humanos , Gotas Lipídicas/metabolismo , Pirazinas , Superóxidos/metabolismo
12.
Phytother Res ; 36(4): 1708-1723, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35234309

RESUMEN

Diabetes mellitus (DM) is one of the most common complications in patients with ulcerative colitis (UC). Curcumin has a wide range of bioactive and pharmacological properties and is commonly used as an adjunct to the treatment of UC and DM. However, the role of curcumin in UC complicated by DM has not been elucidated. Therefore, this study was conducted to construct a model of UC complicating diabetes by inducing UC in DB mice (spontaneously diabetic) with dextran sodium sulfate. In this study, curcumin (100 mg/kg/day) significantly improved the symptoms of diabetes complicated by UC, with a lower insulin level, heavier weight, longer and lighter colons, fewer mucosal ulcers and less inflammatory cell infiltration. Moreover, compared to untreated DB mice with colitis, curcumin-treated mice showed weaker Th17 responses and stronger Treg responses. In addition, curcumin regulated the diversity and relative abundance of intestinal microbiota in mice with UC complicated by DM at the phylum, class, order, family and genus levels. Collectively, curcumin effectively alleviated colitis in mice with type 2 diabetes mellitus by restoring the homeostasis of Th17/Treg and improving the composition of the intestinal microbiota.


Asunto(s)
Colitis Ulcerosa , Colitis , Curcumina , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Animales , Colitis/tratamiento farmacológico , Colitis Ulcerosa/tratamiento farmacológico , Colon , Curcumina/farmacología , Curcumina/uso terapéutico , Sulfato de Dextran , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Modelos Animales de Enfermedad , Homeostasis , Humanos , Ratones , Ratones Endogámicos C57BL , Linfocitos T Reguladores/metabolismo
13.
ACS Appl Mater Interfaces ; 12(23): 25572-25580, 2020 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-32412741

RESUMEN

Reactive oxygen species-mediated tumor chemodynamic therapy and photodynamic therapy have captured extensive attention in practical cancer combination therapies. However, the severe treatment conditions and the hypoxic microenvironment of solid tumors significantly limit the efficacy of these therapies. This work demonstrates the design and fabrication of a multifunctional persistent luminescence nanoplatform (PHFI, refers to PLNP-HSA-Fe3+-IR780) for cancer multimodal imaging and effective photoenhanced combination therapy. The near-infrared-emitted persistent luminescence nanoparticles (PLNP) was modified with human serum albumin (HSA) combined with an IR780 probe and Fe3+. The synthesized PHFI possesses high longitudinal relaxivity, obvious photoacoustic contrast signals, and long-lasting persistent luminescence, indicating that PHFI can be used for cancer magnetic resonance imaging, photoacoustic imaging, and persistent luminescence multimodal imaging. PHFI shows intrinsic photoenhanced Fenton-like catalytic activities as well as photodynamic and photothermal effects and thereby can effectively overcome severe treatment conditions for killing tumor cells. It is worth noting that PHFI serving as a rechargeable internal light source for photoenhanced combination therapy was first disclosed. We believe that our work shows the great potential of PHFI for cancer theranostics and will advance the development of PLNP-based nanoplatforms in tumor catalytic therapy.


Asunto(s)
Sustancias Luminiscentes/uso terapéutico , Nanopartículas/uso terapéutico , Neoplasias/diagnóstico por imagen , Neoplasias/tratamiento farmacológico , Animales , Bencidinas/química , Catálisis/efectos de la radiación , Línea Celular Tumoral , Compuestos Cromogénicos/química , Humanos , Peróxido de Hidrógeno/química , Hipotermia Inducida/métodos , Rayos Infrarrojos , Hierro/química , Sustancias Luminiscentes/química , Sustancias Luminiscentes/efectos de la radiación , Ratones Endogámicos BALB C , Nanopartículas/química , Nanopartículas/efectos de la radiación , Fotoquimioterapia/métodos , Medicina de Precisión/métodos , Especies Reactivas de Oxígeno/metabolismo , Albúmina Sérica Humana/química
14.
J Phys Chem B ; 110(43): 21680-3, 2006 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-17064125

RESUMEN

A simple method based on a hydrothermal process using alkali salts as mineralizers is proposed for the synthesis of aligned bunches of boehmite (gamma-AlOOH) nanowires without a template's assistance. Most bunches of aligned boehmite nanowires are constructed by two separated shorter bundles with widths of 700 to approximately 800 nm and lengths of about 1 microm. XRD patterns, FTIR spectra, and SEM and TEM images were used to characterize the products. The specific surface area and pore-size distribution of the obtained product as determined by gas-sorption measurements show that the boehmite bundles possess a high BET surface area and porosity properties. The importance of adding Na2B4O7 salts for the formation of bundle morphologies has been discussed.

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