Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 42
Filtrar
Más filtros












Base de datos
Intervalo de año de publicación
1.
Zhongguo Zhong Yao Za Zhi ; 49(12): 3185-3193, 2024 Jun.
Artículo en Chino | MEDLINE | ID: mdl-39041079

RESUMEN

Peptidomics was employed to systematically analyze the characteristic peptides in Galli Gigerii Endothelium Corneum and its adulterants and establish a method for distinguishing Galli Gigerii Endothelium Corneum from its adulterants, including the gizzard membranes from ducks, geese, and pigeons. UPLC-Q-Exactive Orbitrap-MS was combined with multivariate statistical analysis to analyze the peptides in Galli Gigerii Endothelium Corneum and its adulterants. The structures of peptides were identified by pNovo combined with manual recognition of spectra, and synthetic peptide standards were used for validation. LC-MS/MS was used to optimize the sample pre-processing conditions, including the extraction procedure, extraction time, extraction solvents, and solvent volumes, for the characteristic peptide LESY in Galli Gigerii Endothelium Corneum. Multiple reaction monitoring(MRM) in the ESI~+ mode with m/z 511.24→269.11 and 511.24→243.13 as detection ions was employed for qualitative and quantitative analyses. The established UPLC-MS/MS method demonstrated good specificity, stability, and durability. The content of LESY in 16 batches of Galli Gigerii Endothelium Corneum samples ranged from 55.03 to 113.36 µg·g~(-1). Additionally, a qualitative detection method for the common peptide RDPVLVSR in adulterants was established with m/z 471.28→785.45 and 471.28→670.41 as the detection ions. This study established a convenient, rapid, and accurate detection method for the characteristic peptides in Galli Gigerii Endothelium Corneum and its adulterants. The method possesses good specificity, stability, and durability, providing a valuable reference for the identification and quality control of Galli Gigerii Endothelium Corneum and other traditional Chinese medicines derived from animal sources.


Asunto(s)
Péptidos , Espectrometría de Masas en Tándem , Espectrometría de Masas en Tándem/métodos , Animales , Cromatografía Líquida de Alta Presión/métodos , Péptidos/química , Péptidos/análisis , Endotelio/química , Pollos , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/análisis , Proteómica/métodos , Contaminación de Medicamentos , Cromatografía Líquida con Espectrometría de Masas
2.
J Anal Methods Chem ; 2023: 9030015, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36760656

RESUMEN

Cistanche tubulosa (Schenk) R. Wight is a valuable herbal medicine in China. The study aimed to explore the potential mechanisms of C. tubulosa on antioxidant activity using spectrum-effect relationship and network pharmacology and the possibilities of utilizing herbal dregs. In this work, different extracts of C. tubulosa, including herbal materials, water extracts, and herbal residues, were evaluated using high-performance liquid chromatography (HPLC) technology. In addition, the antioxidant activities were estimated in vitro, including 2, 2-diphenyl-1-picrylhydrazyl; superoxide anion; and hydroxyl radical scavenging assays. The spectrum-effect relationships between the HPLC fingerprints and the biological capabilities were analyzed via partial least squares regression, bivariate correlation analysis, and redundancy analysis. Furthermore, network pharmacology was used to predict potential mechanisms of C. tubulosa in the treatment of antioxidant-related diseases. According to the results, eleven common peaks were shared by different extracts. Geniposidic acid, echinacoside, verbascoside, tubuloside A, and isoacteoside were quantified and compared among different forms of C. tubulosa. The spectrum-effect relationship study indicated that peak A 6 might be the most decisive component among the three forms. Based on network pharmacology, there were 159 target genes shared by active components and antioxidant-related diseases. Targets related to antioxidant activity and relevant pathways were discussed. Our results provide a theoretical basis for recycling the herbal residues and the potential mechanisms of C. tubulosa in the treatment of antioxidant-related diseases.

3.
Front Plant Sci ; 13: 1092643, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36618650

RESUMEN

Background: Understanding the spatial distribution of active compounds can effectively evaluate the quality of decoction pieces of traditional Chinese medicine (TCM). Traditional methods are economical and practical but lack chemical information on the original distribution. Time-of-flight secondary ion mass spectrometry (TOF-SIMS), with the advantage of non-destructive detection of samples, can directly analyze the distribution of chemical compounds on the surface of various samples. Methods: In this study, TOF-SIMS image analysis technology was used to detect TCM for the first time. Taking Coptis rhizome (CR) as an example, a commonly used TCM, the distribution of the compounds in the cross-section of CR was studied. Meanwhile, ultra-high-performance liquid chromatography coupled with triple quadrupole mass spectrometry (UPLCQQQ-MS/MS) was used to verify the results of TOF-SIMS. Results: The distribution of nine active compounds: berberine, epiberberine, coptisine, palmatine, columbamine, jatrorrhizine, tetrahydricheilanthifolinium, and oxyberberine, was well imaged in the cross-section of CR by TOF-SIMS. The content of berberine and epiberberine was the highest; Palmatine distribution in the pith was more than that in other parts; Oxyberberine was mainly concentrated in the cork and xylem rays. Normalization analysis showed contents of these compounds increased along with the growth years. The result was consistent with UPLC-QQQ-MS/MS. Conclusion: The TOF-SIMS method can display the spatial distribution status of the active compounds of herbs, providing a basis for selecting the medicine site with non-destructive and fast detection.

4.
Int J Hypertens ; 2021: 3066007, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34594579

RESUMEN

This study aimed to investigate the predictive value of lipid accumulation product (LAP) in hypertension in Chinese population older than 65 years. A total of 2092 adults from the communities in Pudong New Area of Shanghai were included in this cross-sectional study. The participants filled in questionnaire and received anthropometric and laboratory examinations. The receiver operating characteristics curve (ROC) was used to analyze the predictive value of different risk factors in hypertension. Results showed that LAP was closely related to hypertension (adjusted OR: 1.011, 95% CI: 1.007-1.015). In females, LAP, fasting blood glucose (FPG), and body mass index (BMI) were associated with hypertension; in males, triglycerides (TG) and waist circumference (WC) were related to hypertension. LAP (AUC = 0.655, 95% CI: 0.632-0.679) was better than neck circumference (NC) and BMI in predicting hypertension. When the cutoff value was 33.5, LAP had the best predictive performance. In males, LAP at 36.72 and 56.76 had the best predictive performance in males (AUC = 0.663, 95% CI: 0.629-0.697) and females (AUC = 0.650, 95% CI: 0.618-0.682), respectively. In conclusion, LAP is a risk factor of hypertension in the elderly. For hypertension, BMI, FPG, and LAP have favorable predictive performance in females, and WC and TG have better predictive performance in males.

5.
Artículo en Inglés | MEDLINE | ID: mdl-34559622

RESUMEN

A Gram-stain-positive and motile bacterial strain, designated IB182363T, was isolated from surface seawater of the South China Sea. Cells grew at pH 5.0-9.5 (optimum, pH 7.0-8.0), 20-40 °C (optimum, 30 °C) and with 1-8 % (w/v) NaCl (optimum, 2-4 %). On the basis of 16S rRNA gene sequence analysis, strain IB182363T was affiliated to the genus Paenibacillus and the closest phylogenetically related species was Paenibacillus ginsengarvi DSM18677T with 96.9 % sequence similarity. The values of whole genome average nucleotide identity analysis and digital DNA-DNA hybridization between the isolate and the closely related type strains were less than 86.3 and 25.6 %, respectively. Chemotaxonomic analysis revealed that strain IB182363T possessed meso-diaminopimelic acid in the cell-wall peptidoglycan and contained menaquinone MK-7 as the predominant isoprenoid quinone. The major cellular fatty acids were anteiso-C15 : 0, C16 : 0 and iso-C16 : 0. The polar lipids comprised phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, one unidentified glycolipid, two unidentified aminolipids, two unidentified phospholipids and four unidentified aminophospholipids. The genomic DNA G+C content was 54.5 mol%. On the basis of the above results, strain IB182363T represents a novel species of the genus Paenibacillus, for which we propose the name Paenibacillus oceani sp. nov. with the type strain IB182363T (=MCCC 1K04630T=JCM 34214T).


Asunto(s)
Ácidos Grasos , Paenibacillus , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Paenibacillus/genética , Fosfolípidos , Filogenia , ARN Ribosómico 16S/genética , Agua de Mar , Análisis de Secuencia de ADN
6.
Anal Sci ; 37(12): 1821-1824, 2021 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-34148924

RESUMEN

A simultaneously HPLC detection method for cannabidiolic acid (CBDA), cannabidiol (CBD), cannabinol (CBN), Δ9-tetrahydrocannabinol (THC), tetrahydro-cannabinolic acid (THCA) in 3 kinds of cosmetics matrix containing hemp leaf extract was developed. The extraction and HPLC conditions were optimized, and a methodological verification was also carried out. The results showed that this method had a good linear relationship in the range of 0.25 - 50 µg/mL with LOD values for 5 cannabinoids all between 0.10 - 0.25 µg/g. The recovery rates of 5 cannabinoids in 3 different cosmetics matrixes were between 90.1 - 108.5%, and the RSD values were all below 4.4%. These results indicated that this method had the advantages of simple operation, high sensitivity, and good accuracy. Through the testing of 6 kinds of hemp cosmetics, it was found that such cosmetics had uneven quality. The establishment of this method can lay a methodological foundation for establishing relevant testing method standards.


Asunto(s)
Cannabinoides , Cannabis , Cosméticos , Cannabinoides/análisis , Cromatografía Líquida de Alta Presión
7.
Front Pharmacol ; 12: 636457, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34012394

RESUMEN

Tao-He-Cheng-Qi decoction (THCQ) is an effective traditional Chinese medicine used to treat intracerebral hemorrhage (ICH). This study was performed to investigate the possible neuroprotective effect of THCQ decoction on secondary brain damage in rats with intracerebral hemorrhage and to elucidate the potential mechanism based on a metabolomics approach. Sprague-Dawley (SD) rats were randomly divided into five groups: the sham group, collagenase-induced ICH model group, THCQ low-dose (THCQ-L)-treated group, THCQ moderate-dose (THCQ-M)-treated group and THCQ high-dose (THCQ-H)-treated group. Following 3 days of treatment, behavioral changes and histopathological lesions in the brain were estimated. Untargeted metabolomics analysis with multivariate statistics was performed by using ultrahigh-performance liquid chromatography-mass spectrometry (UPLC-Q-Exactive Orbitrap MS). THCQ treatment at two dosages (5.64 and 11.27 g/kg·d) remarkably improved behavior (p < 0.05), brain water content (BMC) and hemorheology (p < 0.05) and improved brain nerve tissue pathology and inflammatory infiltration in ICH rats. Moreover, a metabolomic analysis demonstrated that the serum metabolic profiles of ICH patients were significantly different between the sham group and the ICH-induced model group. Twenty-seven biomarkers were identified that potentially predict the clinical benefits of THCQ decoction. Of these, 4 biomarkers were found to be THCQ-H group-specific, while others were shared between two clusters. These metabolites are mainly involved in amino acid metabolism and glutamate-mediated cell excitotoxicity, lipid metabolism-mediated oxidative stress, and mitochondrial dysfunction caused by energy metabolism disorders. In addition, a correlation analysis showed that the behavioral scores, brain water content and hemorheology were correlated with levels of serum metabolites derived from amino acid and lipid metabolism. In conclusion, the results indicate that THCQ decoction significantly attenuates ICH-induced secondary brain injury, which could be mediated by improving metabolic disorders in cerebral hemorrhage rats.

10.
Zhongguo Zhong Yao Za Zhi ; 45(14): 3459-3466, 2020 Jul.
Artículo en Chino | MEDLINE | ID: mdl-32726062

RESUMEN

The present study was performed to establish the UPLC fingerprints of Bolbostemmatis Rhizoma and determine the contents of three saponins by quantitative analysis of multi-components by single marker(QAMS), and provide basis for quality evaluation of Bolbostemmatis Rhizoma. The analysis was carried out on an analytical column of Waters Cortecs T3(2.1 mm×100 mm,1.6 µm)with gradient elution by acetonitrile-0.1% phosphoric acid solution, at a flow rate of 0.3 mL·min~(-1). The detection wavelength was 203 nm, the column temperature was 30 ℃ and the injection volume was 1 µL. The UPLC fingerprints of Bolbostemmatis Rhizoma were established and evaluated by similarity calculation, cluster analysis and principal component analysis. The relative calibration factors of toberoside B and toberoside C were determined with toberoside A as internal reference. The content was calculated by relative calibration factors to develop a method of QAMS. Comparing the results of QAMS with those of ESM, the accuracy and feasibility of one-eva-luation and multi-evaluation can be determined. RESULTS:: showed that the fingerprints of 19 batches of Bolbostemmatis Rhizoma have four common peaks with similarities ranging from 0.754 to 1.000. Cluster analysis and principal component analysis classified 19 batches of Bolbostemmatis Rhizoma into three categories, which was consistent with the similarity evaluation results. The relative deviation between the content of tubeicosides B and C in 19 batches of Bolbostemmatis Rhizoma determined by QAMS and ESM is less than 5.0%, indicating that there was no significant difference between the two methods. Therefore, the UPLC fingerprints combined with QAMS and similarity evaluation can be effectively used to evaluate the quality of Bolbostemmatis Rhizoma.


Asunto(s)
Medicamentos Herbarios Chinos , Cromatografía Líquida de Alta Presión , Análisis de Componente Principal , Control de Calidad , Rizoma
11.
Vet Res ; 50(1): 26, 2019 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-30992061

RESUMEN

Thioredoxins (Trxs) play an important role in defending against oxidative stress and keeping disulfide bonding correct to maintain protein function. Edwardsiella piscicida, a severe fish pathogen, has been shown to encode several thioredoxins including TrxA, TrxC, and TrxH, but their biological roles remain unknown. In this study, we characterized TrxH of E. piscicida (named TrxHEp) and examined its expression and function. TrxHEp is composed of 125 residues and possesses typical thioredoxin H motifs. Expression of trxHEp was upregulated under conditions of oxidative stress, iron starvation, low pH, and during infection of host cells. trxHEp expression was also regulated by ferric uptake regulator (Fur), an important global regulatory of E. piscicida. Compared to the wild type TX01, a markerless trxHEp in-frame mutant strain TX01∆trxH exhibited markedly compromised tolerance of the pathogen to hydrogen peroxide, acid stress, and iron deficiency. Deletion of trxHEp significantly retarded bacterial biofilm growth and decreased resistance against serum killing. Pathogenicity analysis shows that the inactivation of trxHEp significantly impaired the ability of E. piscicida to invade host cells, reproduce in macrophages, and infect host tissues. Introduction of a trans-expressed trxH gene restored the lost virulence of TX01∆trxH. There is likely to be a complex relationship of functional complementation or expression regulation between TrxH and another two thioredoxins, TrxA and TrxC, of E. piscicida. This is the first functional report of TrxH in fish pathogens, and the findings suggest that TrxHEp is essential for coping with adverse circumstances and contributes to host infection of E. piscicida.


Asunto(s)
Proteínas Bacterianas/genética , Edwardsiella/fisiología , Edwardsiella/patogenicidad , Regulación Bacteriana de la Expresión Génica , Tiorredoxina h/genética , Transcriptoma , Adaptación Fisiológica/genética , Secuencia de Aminoácidos , Animales , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Edwardsiella/genética , Alineación de Secuencia , Tiorredoxina h/química , Tiorredoxina h/metabolismo , Virulencia
12.
Phytochemistry ; 151: 42-49, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29665475

RESUMEN

Eleven previously undescribed limonoids, trichisins A-K, including eight structural analogues A-H of trijugin and three H-J mexicanolide derivatives, together with two known mexicanolide derivatives were isolated from the fruits of Heynea trijuga Roxb. ex Sims. The structure determination was based on extensive physical data analyses (NMR, MS), and their basic skeletons and the absolute configurations of trichisins A, B, E, K and trichiconnarone A were assigned via X-ray crystallographic analysis (Cu Kα radiation). The hemiketal motifs in trijugins A, B, and E-G are rare in limonoids. Bioactivity screenings suggested that the trijugin H and mexicanolide-type trichiconnarones A and B limonoids were effective in reversing resistance in MCF-7/DOX cells at a nontoxic concentration of 50 µM with IC50 values of 12.45, 10.86, and 14.96 µM, respectively.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Frutas/química , Limoninas/farmacología , Meliaceae/química , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Limoninas/química , Limoninas/aislamiento & purificación , Modelos Moleculares , Conformación Molecular , Relación Estructura-Actividad
13.
Zhongguo Zhong Yao Za Zhi ; 43(4): 659-664, 2018 Feb.
Artículo en Chino | MEDLINE | ID: mdl-29600637

RESUMEN

An HPLC-ELSD method for quantitation of GCANa, CA, HDCA, CDCA and DCA in artificial cow-bezoar was developed in this study. The chromatographic separation was performed using a Wondasil CC18(4.6 mmχ250 mm,5 µm) column at a column temperature of 25 °C and liquid flow-rate of 1.0 mL·min⁻¹. Acetonitrile and 0.2% formic acid solution were used as mobile phase with a linear gradient and injection volume was 10 µL. An ELSD was used with a nitrogen flow-rate of 2.3 L·h⁻¹at a drift tube temperature of 110 °C. Some chemometric methods were applied in data procession and analysis for exploration of the markers of quality difference. The accurate and simple method is suitable for the quality evaluation and the quality control of artificial cow-bezoar.


Asunto(s)
Bezoares , Medicina Tradicional China , Animales , Bovinos , Cromatografía Líquida de Alta Presión , Control de Calidad
14.
Fitoterapia ; 125: 72-77, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29288024

RESUMEN

Phytochemical investigation of the fruits from Trichilia connaroides led to the isolation of four rare 1,2-seco phragmalin-type limonoids (1-4) with C-7/28 δ-lactone ring along with two known triterpenoids (5-6). An oxygen bridge between C-1 and C-2 formed an rare 9-oxa-tricyclo[3.3.2.17,10]undecane-2-ene moiety in structure of 1 and 2, and 3-4 possessed a bicyclo[5.2.14,10]decane skeleton. Their structures were established based on extensive spectroscopic methods and their absolute configurations of 1 were confirmed by TDDFT/ECD calculation and comparative analysis. Compounds 5-6 showed moderate inhibitory effects on Hela tumor cell lines with inhibition ratio values of 83.8% and 87.1% at concentration 40µM, respectively.


Asunto(s)
Frutas/química , Limoninas/aislamiento & purificación , Meliaceae/química , Células A549 , China , Células HeLa , Humanos , Limoninas/química , Estructura Molecular
15.
RSC Adv ; 8(19): 10437-10445, 2018 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-35540464

RESUMEN

Eleven new mexicanolide-type limonoids, cipadessains A-K (1-11), were isolated from the fruits of Cipadessa cinerascens (Pellegr) Hand.-Mazz. Their planar structures were determined based on IR, UV, 1D and 2D NMR spectra and HRESIMS data. The absolute configuration of 1 was elucidated by single-crystal X-ray diffraction using mirror Cu Kα radiation, and that of compounds 2-8 were determined by ECD analysis. Two mexicanolides bearing methoxybutenolide moiety originated from the furan ring 3 and 6, showed significant cytotoxicity against HepG2 cell line with IC50 values of 5.23 ± 0.12, 8.67 ± 1.02 µM, respectively; and NO inhibitory activities in LPS-activated RAW 264.7 macrophages at nontoxic concentration (IC50 5.79 ± 0.18, 6.93 ± 0.89 µM, respectively).

16.
Ground Water ; 56(4): 594-609, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-28992375

RESUMEN

In this study, a water-air two-phase flow model was employed to investigate the formation, extension, and dissipation of groundwater ridging induced by recharge events in a hypothetical hillslope-riparian zone, considering interactions between the liquid and gas phases in soil voids. The simulation results show that, after a rain begins, the groundwater table near the stream is elevated instantaneously and significantly, thereby generating a pressure gradient driving water toward both the stream (the discharge of groundwater to the stream) and upslope (the extension of groundwater ridging into upslope). Meanwhile, the airflow upslope triggered by the advancing wetting front moves downward gradually. Therefore, the extension of groundwater ridging into upslope and the downward airflow interact within a certain region. After the rain stops, groundwater ridging near the stream declines quickly while the airflow in the lower part of upslope is still moving into the hillslope. Thus, the airflow upslope mitigates the dissipation of groundwater ridging. Additionally, the development of groundwater ridging under different conditions, including rain intensity, intrinsic permeability, capillary fringe height, and initial groundwater table, was analyzed. Changes in intrinsic permeability affect the magnitude of groundwater ridging near the stream, as well as the downward speed of airflow, thereby generating highly complex responses. The capillary fringe is not a controlling factor but an influence factor on the formation of groundwater ridging, which is mainly related to the antecedent moisture. It was demonstrated that groundwater ridging also occurs where an unsaturated zone occurs above the capillary fringe with a subsurface lateral flow.


Asunto(s)
Agua Subterránea , Movimientos del Agua , Lluvia , Ríos , Suelo
17.
Org Lett ; 19(17): 4568-4571, 2017 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-28820603

RESUMEN

Walrobsins A (1) and B (2), two limonoids featuring an unprecedented 5-oxatricyclo[5.4.11,4]hendecane ring system, were isolated from the root barks of Walsura robusta. Their structures, including their absolute configurations, were determined by analyses of HR-ESIMS, 1D/2D NMR, and X-ray crystallography. Compounds 1 and 2 possessed a stable hemiketal structure formed between the OH-11 and 3-carbonyl group in the hexatomic oxoheterocyclic ring. Compound 1 showed significant anti-inflammatory activity with an IC50 value of 7.8 µM and inhibited the expression of iNOS and IL-1ß in a dose-dependent manner.


Asunto(s)
Meliaceae , Cristalografía por Rayos X , Limoninas , Conformación Molecular , Estructura Molecular
18.
Zhongguo Zhong Yao Za Zhi ; 42(11): 2117-2122, 2017 Jun.
Artículo en Chino | MEDLINE | ID: mdl-28822157

RESUMEN

A method of thin-layer fingerprinting chromatogram of artificial cow-bezoar was established with the developing solvent consisting of cyclohexane, ethyl acetate, acetic acid and methanol (2∶7∶1∶2), and 10% sulfuric acid ethanol solution sprayed as colour-developing agent. After heated at 105 ℃, TLC was recorded as an image in ultraviolet light at 366 nm which was converted into grayscale. By the gray value extracted from the grayscale, the multivariate data obtained from TLC of samples could be analyzed by chemometric method. The results indicated that samples from different manufacturers could be distinguished by this method and some specific bands were found out. All in one, this simple and practical method was suitable for the evaluation of quality difference.


Asunto(s)
Bezoares/clasificación , Animales , Bovinos , Cromatografía , Metanol , Solventes
19.
Ground Water ; 55(3): 375-386, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-27997692

RESUMEN

An investigation of groundwater table fluctuations induced by rainfall should consider interactions between the liquid and gas phases in soils. In this study, a water-air two-phase flow model was initially verified by simulating an infiltration experiment. It was then employed to model the interactions between liquid and gas phases regarding actions of airflow on the groundwater table and the fluctuations of the phreatic level and water level in the well induced by rainfall. The effects of airflo7w caused by rainfall on phreatic level fluctuations were also studied quantitatively by comparing the results obtained using the proposed model with those obtained from a water single-phase flow model. The simulation results show that in addition to actual recharge, compressed airflow in unsaturated zones causes the phreatic level to increase, but the rise in the phreatic level is lower than that in the pore-air pressure head in unsaturated zones due to the mitigation of capillary fringe. The existence of airflow enhances the phreatic level rise during and after rainfall. In addition, the water level in the well, pushed by the phreatic level fluctuations, varies similarly to the phreatic level, but it experiences somewhat delayed and slightly attenuated. The Lisse effect precisely reflects the phreatic level fluctuations before actual recharge. Furthermore, the fluctuations in the phreatic level and water level in the well and the contributions of airflow to phreatic level fluctuations are affected by many factors: rain intensity, initial moisture, overlying aquitard, groundwater table depths, and screen depths of the well.


Asunto(s)
Agua Subterránea , Modelos Teóricos , Lluvia , Suelo , Movimientos del Agua
20.
Sci Rep ; 6: 32402, 2016 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-27573057

RESUMEN

Elaborate architectural manipulation of nanohybrids with multi-components into controllable 3D hierarchical structures is of great significance for both fundamental scientific interest and realization of various functionalities, yet remains a great challenge because different materials with distinct physical/chemical properties could hardly be incorporated simultaneously into the synthesis process. Here, we develop a novel one-pot cyanogel-bridged synthetic approach for the generation of 3D flower-like metal/Prussian blue analogue nanohybrids, namely PdCo/Pd-hexacyanocobaltate for the first time. The judicious introduction of polyethylene glycol (PEG) and the formation of cyanogel are prerequisite for the successful fabrication of such fascinating hierarchical nanostructures. Due to the unique 3D hierarchical structure and the synergistic effect between hybrid components, the as-prepared hybrid nanoflowers exhibit a remarkable catalytic activity and durability toward the reduction of Rhodamine B (RhB) by NaBH4. We expect that the obtained hybrid nanoflowers may hold great promises in water remediation field and beyond. Furthermore, the facile synthetic strategy presented here for synthesizing functional hybrid materials can be extendable for the synthesis of various functional hybrid nanomaterials owing to its versatility and feasibility.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...