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1.
ACS Appl Mater Interfaces ; 16(20): 26217-26225, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38733352

RESUMEN

Among various anode materials, SiOx is regarded as the next generation of promising anode due to its advantages of high theoretical capacity with 2680 mA h g-1, low lithium voltage platform, and rich natural resources. However, the pure SiOx-based materials have slow lithium storage kinetics attributed to their low electron/ion conductive properties and the large volume change during lithiation/delithiation, restricting their practical application. Optimizing the SiOx material structures and the fabricating methods to mitigate these fatal defects and adapt to the market demand for energy density is critical. Hence, SiOx material with TiO1-xNx phase modification has been prepared by simple, low-cost, and scalable ball milling and then combined with nitridation. Consequently, based on the TiO1-xNx modified layer, which boosts high ionic/electronic conductivity, chemical stability, and excellent mechanical properties, the SiOx@TON-10 electrode shows highly stable lithium-ion storage performance for lithium-ion half/full batteries due to a stable solid-electrolyte interface layer, fast Li+ transport channel, and alleviative volumetric expansion, further verifying its practical feasibility and universal applicability.

2.
Small ; 20(27): e2312091, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38308418

RESUMEN

Grafted biopolymer binders are demonstrated to improve the processability and cycling stability of the silicon (Si) nanoparticle anodes. However, there is little systematical exploration regarding the relationship between grafting density and performance of grafted binder for Si anodes, especially when Si particles exceed the critical breaking size. Herein, a series of guar gum grafted polyacrylamide (GP) binders with different grafting densities are designed and prepared to determine the optimal grafting density for maximizing the electrochemical performance of Si submicroparticle (SiSMP) anodes. Among various GP binders, GP5 with recommended grafting density demonstrates the strongest adhesion strength, best mechanical properties, and highest intrinsic ionic conductivity. These characteristics enable the SiSMP electrodes to sustain the electrode integrity and accelerate lithium-ion transport kinetics during cycling, resulting in high capacity and stable cyclability. The superior role of GP5 binder in enabling robust structure and stable interface of SiSMP electrodes is revealed through the PeakForce atomic force microscopy and in situ differential electrochemical mass spectrometry. Furthermore, the stable cyclabilities of high-loading SiSMP@GP5 electrode with ultralow GP5 content (1 wt%) at high areal capacity as well as the good cyclability of Ah-level LiNi0.8Co0.1Mn0.1O2/SiSMP@GP5 pouch cell strongly confirms the practical viability of the GP5 binder.

3.
Ren Fail ; 46(1): 2296002, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38186345

RESUMEN

OBJECTIVE: To explore the relationship between the serum uric acid to creatinine (UA/Cr) ratio and the prevalence of hypertension. METHODS: In this cross-sectional study, we included 8571 individuals from the China Health and Nutrition Survey. Logistic regression analysis and restricted cubic spline (RCS) were used to analyze the relationship between the UA/Cr ratio and hypertension. RESULTS: Compared with individuals without hypertension, individuals with hypertension had higher UA/Cr ratios. Multivariate logistic regression analysis showed that a higher UA/Cr ratio was closely related to a higher risk of hypertension (as a continuous variable, OR: 1.054, 95% CI: 1.014-1.095, p = 0.007; as a categorical variable, Q3 vs. Q1, OR: 1.183, 95% CI: 1.011-1.384, p = 0.035; Q4 vs. Q1, OR: 1.347, 95% CI: 1.146-1.582, p < 0.001). Subgroup analysis revealed that the correlation between the UA/Cr ratio and hypertension risk was stable in all subgroups except for the subgroup with diabetes and the subgroup with a BMI ≥ 28 kg/m2 (p < 0.05). Sensitivity analysis confirmed the robustness of the relationship between a higher UA/Cr ratio and a higher risk of hypertension (p < 0.05). The RCS showed that the UA/Cr ratio was nonlinearly related to hypertension risk. Further threshold effect showed that only a UA/Cr ratio less than 5.0 was related to hypertension risk (OR: 1.178, 95% CI: 1.086-1.278, p < 0.001), and the 2-piecewise linear regression model was superior to the 1-line linear regression model (p < 0.05). CONCLUSION: The UA/Cr ratio was associated with the prevalence of hypertension.


Asunto(s)
Hipertensión , Ácido Úrico , Humanos , Prevalencia , Creatinina , Estudios Transversales , Hipertensión/epidemiología
5.
ACS Appl Mater Interfaces ; 14(51): 56910-56918, 2022 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-36515974

RESUMEN

The large volume expansion hinders the commercial application of silicon oxide (SiOx) anodes in lithium-ion batteries. Recent studies show that binders play a vital role in mitigating the volume change of SiOx electrodes. Herein, we introduce the small molecule tannic acid (TA) with high branching into the linear poly(acrylic acid) (PAA) binder for SiOx anodes. The three-dimensional (3D) crosslinked network with multiple hydrogen bonds is formed by the incorporation of abundant hydroxyl groups with unique carboxyl groups, which increases the interfacial adhesive strength with SiOx particles. As a consequence, SiOx electrodes based on the PAA-TA binder show an excellent cycling performance with a high specific capacity of 1025 mA h g-1 at 500 mA g-1 after 250 cycles. Moreover, the SiOx||NCM811 full cell exhibits a reversible capacity of 143 mA h g-1 corresponding to 87.4% capacity retention after 100 cycles.

6.
Artículo en Inglés | MEDLINE | ID: mdl-36314536

RESUMEN

Micron-sized silicon oxide (SiOx) has been regarded as a promising anode material for new-generation lithium-ion batteries due to its high capacity and low cost. However, the distinct volume expansion during the repeated (de)lithiation process and poor conductivity can lead to structural collapse of the electrode and capacity fading. In this study, SiOx anode materials coated with TiO0.6N0.4 layers are fabricated by a facile solvothermal and thermal reduction technique. The TiO0.6N0.4 layers are homogeneously dispersed on SiOx particles and form an intimate contact. The TiO0.6N0.4 layers can enhance the conductivity and suppress volume expansion of the SiOx anode, which facilitate ion/electron transport and maintain the integrity of the overall electrode structure. The as-prepared SiOx-TiON-200 composites demonstrate a high reversible capacity of 854 mAh g-1 at 0.5 A g-1 with a mass loading of 2.0 mg cm-2 after 250 cycles. This surface modification technique could be extended to other anodes with low conductivity and large volume expansion for lithium-ion batteries.

7.
ACS Appl Mater Interfaces ; 14(16): 18625-18633, 2022 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-35417145

RESUMEN

Silicon oxide (SiOx) has outstanding capacity and stable lithium-ion uptake/removal electrochemistry as a lithium-ion anode material; however, its practical massive commercialization is encumbered by unavoidable challenges, such as dynamic volume changes during cycling and inherently inferior ionic conductivities. Recent literature has offered a consensus that binders play a critical role in affecting the electrochemical performance of Si-based electrodes. Herein, we report an aqueous binder, γ-polyglutamic acid cross-linked by epichlorohydrin (PGA-ECH), that guarantees enhanced properties for SiOx anodes to implement long-term cycling stability. The abundant amide, carboxyl, and hydroxyl groups in the binder structure form strong interactions with the SiOx surface, which contribute strong interfacial adhesion. The robust covalent interactions and strong supramolecular interactions in the binder ensure mechanical strength and elasticity. Additionally, the interactions between lithium ions and oxygen (nitrogen) atoms of carboxylate (peptide) bonds, which serve as a Lewis base, facilitate the diffusion of lithium ions. A SiOx anode using this PGA-ECH binder exhibits an impressive initial discharge capacity of 1962 mA h g-1 and maintains a high capacity of 900 mA h g-1 after 500 cycles at 500 mA g-1. Meanwhile, the assembled SiOx||LiNi0.6Co0.2MnO0.2 full cell shows a reversible capacity of 155 mA g-1 and displays 73% capacity retention after 100 cycles.

8.
ACS Appl Mater Interfaces ; 13(46): 55092-55101, 2021 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-34762400

RESUMEN

A lithium-sulfur (Li-S) battery based on multielectron chemical reactions is considered as a next-generation energy-storage device because of its ultrahigh energy density. However, practical application of a Li-S battery is limited by the large volume changes, insufficient ion conductivity, and undesired shuttle effect of its sulfur cathode. To address these issues, an aqueous supramolecular binder with multifunctions is developed by cross-linking sericin protein (SP) and phytic acid (PA). The combination of SP and PA allows one to control the volume change of the sulfur cathode, benefit soluble polysulfides absorbing, and facilitate transportation of Li+. Attributed to the above merits, a Li-S battery with the SP-PA binder exhibits a remarkable cycle performance improvement of 200% and 120% after 100 cycles at 0.2 C compared with Li-S batteries with PVDF and SP binders. In particular, the SP-PA binder in the electrode displays admirable flame-retardant performance due to formation of an isolating layer and the release of radicals.

9.
ACS Appl Mater Interfaces ; 13(28): 33066-33074, 2021 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-34251170

RESUMEN

Conventional polymer binder in a lithium-sulfur (Li-S) battery, poly(vinylidene fluoride) (PVDF), suffers from insufficient ion conductivity, poor polysulfide-trapping ability, weak mechanical property, and requirement of organic solvents, which significantly encumber the industrial application of Li-S battery. Herein, a water-soluble binder with trifunctions, covalently cross-linked quaternary ammonium cationic starch (c-QACS), is developed to confront these issues. Similar to the poly(ethylene oxide) solid electrolytes, the c-QACS binder remarkably improves Li+ ion transfer capacity. The abundant O actives endow the c-QACS binder with admirable lithium polysulfide-trapping capability to retard the shuttle effect. In addition, the formed 3D network effectively maintains the electrode integrity during cycling. Benefiting from the above merits, the sulfur cathode with the c-QACS binder demonstrates a performance improvement of 300 and 150% compared with sulfur cathode with PVDF and bulk QACS binder after 100 cycles at 0.2C.

10.
J Hazard Mater ; 393: 122366, 2020 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-32120212

RESUMEN

Thin 2D/2D WO3/g-C3N4 Step-scheme (S-scheme) heterojunction with carbon doping and bridge (C-W/N) was constructed with anionic polyacrylamide (APAM), in which APAM functioned as an assistant templet and a carbon source. APAM and WO3 were inserted into g-C3N4 nanosheet. The carbon, thin planar structure and WO3 with oxygen vacancies result in fast charge transfer, high quantum efficiency and strong driving force for photocatalytic reaction. Consequently, as-prepared C-W/N ternary composite photocatalyst exhibited significantly enhanced photocatalytic performance for tetracycline (TC) degradation under visible light compared to pure g-C3N4, WO3 and other binary composites. Moreover, the material showed high stability and reusability in cyclic TC degradation. The principal intermediate products over C-W/N photocatalyst were revealed by HPLC-MS analysis. Corresponding degradation pathway of TC was also presented in this work. According to the trapping experiments, analysis of electron spin resource (ESR) and band gap, possible charge transfer pathways of C-W/N are proposed and discussed in detail. Based on the results, carbon derived from APAM works not only as electron mediator but also as acceptor for photocatalytic degradation reaction. It is a promising way to further modulate heterojunction for varies applications.


Asunto(s)
Resinas Acrílicas/química , Grafito/química , Compuestos de Nitrógeno/química , Óxidos/química , Tetraciclina/química , Tungsteno/química , Catálisis/efectos de la radiación , Contaminantes Ambientales/química , Grafito/efectos de la radiación , Luz , Compuestos de Nitrógeno/efectos de la radiación , Óxidos/efectos de la radiación , Tungsteno/efectos de la radiación
11.
Int J Clin Exp Pathol ; 12(1): 198-204, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31933734

RESUMEN

The aim of the present study was to analyze the effects of Atractylodesin III (codonopsis pilosula) extract that maintains mitochondrial function, up-regulates Bcl-2, inhibits Caspase-3 activity, and ultimately leads to cardiomyocyte apoptosis in a rat model of acute myocardial infarction (AMI). 30 male Sprague-Dawley rats aged 6 months, weighed 150-200 g were randomly divided into sham operation group (SOG), model group (MG) and intervention group (IG). The IG was intragastrically administered with atractylodesin III (30 mg/kg/d) for 7 days. The model group was treated with (30 mg/kg/d) of sterile saline. After 4.5 h, the heart samples from each group were taken, the myocardial infarct size was detected by 2, 3, 5-triphenyltetrazolium chloride (TTC) staining.After ematoxylin & Eosin (HE) staining apoptosis indices were determined by Terminal deoxynucleotidyl transferase TdT-mediated dUTP Nick-End Labeling (TUNEL) method. Apoptosis-related genes and protein including Bcl-2, Bax, and Caspase-3 expression were determined by quantitative real time polymerase chain reaction (qRT-PCR) and western blot respectively. The infarct size and apoptotic index of the MG were significantly higher than SOG. However, infarct size and apoptotic index were reduced in IGcompared to MG (P < 0.05). The levels of Bax and Caspase-3 in the MG were significantly higher, while Bcl-2 and Bcl-2/Bax were lower than those in the SOG. The IG has lower levels of Bax and Caspase-3, higher levels of Bcl-2 and Bcl-2/Bax (P < 0.05) compared to MG. Atractylodesin III decreased apoptosis of myocardial cells in AMI, up-regulated Bcl-2 expression, and inhibited Bax and Caspase-3 activity.

12.
Chinese Journal of School Health ; (12): 523-526, 2019.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-818812

RESUMEN

Objective@#To compare the effect of two different methods of "3-PR" participatory health education and traditional distribution of publicity materials on health literacy improvement of medical students, to provide a reference for making more effective measure to improve health literacy.@*Methods@#173 Second-grade students in nursing major were selected in a secondary vocational school in Datong City. Two different intervention methods were used to intervene for 8 weeks. The experimental group (92 students) received "3-PR" participatory health education; the traditional health education intervention in the control group(81 students). The "National Residents’ Health Literacy Monitoring Questionnaire 2015" was used to conduct a questionnaire survey on the experimental group and the control group before and after the intervention, and to compare the effects before and after the intervention.@*Results@#The average score of health literacy was (36.04±9.43) points and (36.01±10.17) points before and after intervention in the control group; (35.78±8.91) points and (49.53±13.53) points before and after intervention in the experimental group; No statistical difference between experimental and control group was found before intervention(t=0.18, P=0.86); There was no significant difference in health literacy score before and after intervention for the control group(t=0.03, P=0.98); Health literacy significantly increased in the experimental group after intervention(t=-11.36, P=0.00). Adequate health literacy accounted for 3.70% and 4.94% before and after intervention in the control group and 4.35% and 45.65% in the experimental group before and after intervention. No significant difference was found in adequate health literacy proportion between the two groups before intervention(χ2=0.00, P=1.00). However, the difference showed statistically significant after intervention(χ2=36.58, P=0.00). The change of health literacy score in the control group and the experimental group was (-0.02±7.52) and (12.75±10.77), respectively, accounting for 1.24% decrement and 41.30% increment. The difference between the two groups was statistically significant (t=-8.93, P=0.00). The dimension-and type-specific score of health literacy showed similar pattern.@*Conclusion@#The "3-PR" participatory health education model is more effective than the traditional health education method in improving health literacy, and it could be carried out by multi-disciplinary students.

13.
ACS Appl Mater Interfaces ; 10(40): 34212-34221, 2018 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-30238743

RESUMEN

A harmonized three-component composite system which preserves the characteristics of individual components is of interest in the field of energy storage. Here, we present a graphene-encapsulated MXene Ti2CT x@polyaniline composite (GMP) material realized in a systematically stable configuration with different ternary nanomaterials for supercapacitor electrodes. Due to the different ζ-potentials in a high-pH solution, chemically converted graphene (negatively charged) is thoroughly unfolded to allow full encapsulation, but the MXene Ti2CT x@polyaniline composite with a low positive ζ-potential is easily attracted toward a counter-charged substance. The obtained GMP electrode exhibits improved cycling stability and better electrochemical performance owing to the use of mechanically robust and chemically inert graphene and the densely intercalated conductive polyaniline between the multilayer MXenes. The GMP electrode has a high gravimetric capacitance of 635 F g-1 (volumetric capacitance of 1143 F cm-3) at a current density of 1 A g-1 with excellent cycling stability of 97.54% after 10 000 cycles. Furthermore, the asymmetric pouch-type supercapacitor assembled using the GMP as a positive electrode and graphene as a negative electrode yields a high energy density of 42.3 Wh kg-1 at a power density of 950 W kg-1 and remarkable cycling stability (94.25% after 10 000 cycles at 10 A g-1).

14.
Adv Sci (Weinh) ; 5(5): 1700491, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29876201

RESUMEN

Black phosphorus (BP) is rediscovered as a 2D layered material. Since its first isolation in 2014, 2D BP has triggered tremendous interest in the fields of condensed matter physics, chemistry, and materials science. Given its unique puckered monolayer geometry, 2D BP displays many unprecedented properties and is being explored for use in numerous applications. The flexibility, large surface area, and good electric conductivity of 2D BP make it a promising electrode material for electrochemical energy storage devices (EESDs). Here, the experimental and theoretical progress of 2D BP is presented on the basis of its preparation methods. The structural and physiochemical properties, air instability, passivation, and EESD applications of 2D BP are discussed systemically. Specifically, the latest research findings on utilizing 2D BP in EESDs, such as lithium-ion batteries, supercapacitors, and emerging technologies (lithium-sulfur batteries, magnesium-ion batteries, and sodium-ion batteries), are summarized. On the basis of the current progress, a few personal perspectives on the existing challenges and future research directions in this developing field are provided.

15.
ACS Appl Mater Interfaces ; 9(2): 1395-1406, 2017 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-27936540

RESUMEN

Achieving high energy density while retaining high power density is difficult in electrical double-layer capacitors and in pseudocapacitors considering the origin of different charge storage mechanisms. Rational structural design became an appealing strategy in circumventing these trade-offs between energy and power densities. A hybrid structure consists of chemically converted graphene-encapsulated carbon@nickel-aluminum layered double hydroxide core-shell spheres as spacers among graphene layers (G-CLS) used as an advanced electrode to achieve high energy density while retaining high power density for high-performance supercapacitors. The merits of the proposed architecture are as follows: (1) CLS act as spacers to avoid the close restacking of graphene; (2) highly conductive carbon sphere and graphene preserve the mechanical integrity and improve the electrical conductivity of LDHs hybrid. Thus, the proposed hybrid structure can simultaneously achieve high electrical double-layer capacitance and pseudocapacitance resulting in the overall highly active electrode. The G-CLS electrode exhibited high specific capacitance (1710.5 F g-1 at 1 A g-1) under three-electrode tests. An ASC fabricated using the G-CLS as positive electrode and reduced graphite oxide as negative electrode demonstrated remarkable electrochemical performance. The ASC device operated at 1.4 V and delivered a high energy density of 35.5 Wh kg-1 at a 670.7 W kg-1 power density at 1 A g-1 with an excellent rate capability as well as a robust long-term cycling stability of up to 10 000 cycles.

16.
ScientificWorldJournal ; 2014: 647040, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24558321

RESUMEN

This study was conducted to synthesize a series of nanosized BiOI-TiO2 catalysts to photodegrade Bisphenol A solution. The BiOI-TiO2 nanoparticles were synthesized in the reverse microemulsions, consisting of cyclohexane, Triton X-100, n-hexanol, and aqueous salt solutions. The synthesized particles were characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) surface analyzer, Fourier transform-infrared spectroscopy (FT-IR), ultraviolet-visible light (UV-Vis) absorption spectra and transmission electron microscope (TEM). The photodegradation of Bisphenol A (BPA) in aqueous suspension under visible light irradiation was investigated to explore the feasibility of using the photocatalytic method to treat BPA wastewater. The effects of different molar ratios of BiOI to TiO2 on the photocatalytic activity were discussed. The experimental results revealed that the photocatalytic effect of the BiOI-TiO2 particles was superior to the commercial P25 TiO2. The BPA degradation could be approached by a pseudo-first-order rate expression. The observed reaction rate constant (kobs) was related to nanoparticles dosage and initial solution pH.


Asunto(s)
Bismuto/química , Técnicas de Química Sintética/métodos , Nanopartículas del Metal/química , Fotoquímica/métodos , Titanio/química , Catálisis , Emulsiones , Difracción de Rayos X/métodos
17.
Dalton Trans ; 43(6): 2611-9, 2014 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-24327303

RESUMEN

Rectorite was composited with BiOI to extend its applicability as an applied material with high adsorptive capacity and photocatalytic activity. The facile synthesis process involved ultrasonic irradiation and in situ reaction. The physicochemical properties of the as-prepared samples were characterized by means of X-ray diffraction (XRD), Fourier transform-infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), N2 adsorption-desorption isotherms, and UV-vis diffuse reflectance spectroscopy (UV-vis DRS). Rhodamine B (RhB), a typical organic contaminant, was used as the model contaminant to evaluate the adsorption capacity and photocatalytic performance of the prepared BiOI-rectorite composite. The adsorption process was found to obey pseudo-second-order kinetics. The equilibrium adsorption was well-modeled using the Freundlich adsorption isotherm. High photocatalytic activity under visible light irradiation was observed.

18.
Bing Du Xue Bao ; 30(6): 630-5, 2014 Nov.
Artículo en Chino | MEDLINE | ID: mdl-25868277

RESUMEN

The aim of this study was to understand the enterovirus types and biological features of pediatric cases of HFMD in Sanmenxia City during 2011, and compare the latter to a cohort of healthy children. Stool samples of 55 cases of HFMD and 60 healthy children were collected for the isolation and identification of enteroviruses using RNA extraction and real-time RT-PCR assays. EV71 and CA16 were identified by nucleotide sequencing using virus-specific VP1 primers; for the other enteroviruses, 012/011 and 008/013 primers were used for amplification and sequencing. The results were analysed by sequence alignment with known sequences, and the characteristics of the EV71 VP1 gene were also analyzed. The detection rates for enteroviruses in cases of HFMD and healthy children were 52.73% (29/55) and 18.33% (11/60), respectively. Among these, there were 22 cases of EV71, four cases of CA16 and three cases of other enteroviruses in the cases with HFMD. Eleven healthy children had intestinal viruses, of which nine were Coxsackie B virus strains (81.82%, 9/11). Gene sequencing of the 19 EV71 strains illustrated that they were all subgenotype C4a, but the evolutionary tree showed an obvious clustering between cases from Lingbao City and Lushi County. This study demonstrates that the EV71 subgenotype C4a and CA16 strains were the most common cause of HFMD in Sanmenxia City in 2011, and that Coxsackie B strains were prevalent in healthy children. This finding may indicate that there is a widespread source of recessive infection in the community.


Asunto(s)
Enterovirus Humano A/aislamiento & purificación , Enfermedad de Boca, Mano y Pie/virología , Niño , Preescolar , China/epidemiología , Ciudades/epidemiología , Enterovirus Humano A/clasificación , Enterovirus Humano A/genética , Femenino , Enfermedad de Boca, Mano y Pie/epidemiología , Humanos , Lactante , Masculino , Filogenia , Proteínas Virales/genética
19.
Zhongguo Zhong Yao Za Zhi ; 38(5): 674-7, 2013 Mar.
Artículo en Chino | MEDLINE | ID: mdl-23724673

RESUMEN

OBJECTIVE: To compare Cirsium japonicum characteristics with C. leo and C. leducei, along with the content of buddleoside and pectolinarin, and lay the foundation for the quality control of C. japonicum. METHOD: Samples were collected and the relevant drugs were bought. The samples were divided into root, stem, leaf and flower, and the content of buddleoside and pectolinarin was determine by the HPLC. Chromatographic column: Waters XBridge C18 (4.6 mm x 250 mm), mobile phase: methanol-water (45: 55), measurement wavelength: 326 nm, flow rate: 0.8 mL x min(-1), column temperature: 30 degrees C. RESULT AND CONDUSION: Standard curve equation of buddleoside: Y = 74 064X-47 748, R2 = 0.991. Standard curve equation of pectolinarin: Y = 1 711 64X - 180 707, R2 = 0.999. The content of buddleoside: C. japonicum leaf was 1.987 3%, C. leo leaf 1.412 2%, C. leducei leaf 0.149 2%. The content of buddleoside was lower in root and stem. Pectolinarin was not detected in the C. japonicum and C. leo. The pectolinarin content was 0.069 0% in C. leducei leaf.


Asunto(s)
Cromonas/análisis , Cirsium/química , Medicamentos Herbarios Chinos/análisis , Cromatografía Líquida de Alta Presión , Cromonas/química , Medicamentos Herbarios Chinos/química , Reproducibilidad de los Resultados , Solubilidad , Especificidad de la Especie
20.
Photochem Photobiol ; 88(5): 1205-10, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22530926

RESUMEN

In this paper, Bi(2)O(3) and rare earth (La, Ce)-doped Bi(2)O(3) visible-light-driven photocatalysts were prepared in a Triton X-100/n-hexanol/cyclohexane/water reverse microemulsion. The resulting materials were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET) surface area, photoluminescence spectra (PLS) and UV-Vis diffuse reflectance spectroscopy. The XRD patterns of the as-prepared catalysts calcined at 500 °C exhibited only the characteristic peaks of monoclinic α-Bi(2)O(3). PLS analysis implied that the separation efficiency for electron-hole has been enhanced when Bi(2)O(3) was doped with rare earth. UV-Vis diffuse reflectance spectroscopy measurements presented an extension of light absorption into the visible region. The photocatalytic activity of the samples was evaluated by degradation of methyl orange (MO) and 2,4-dichlorophenol (2,4-DCP). The results displayed that the photocatalytic activity of rare earth-doped Bi(2)O(3) was higher than that of dopant-free Bi(2)O(3). The optimal dopant amount of La or Ce was 1.0 mol%. And the mechanisms of influence on the photocatalytic activity of the catalysts were discussed.


Asunto(s)
Bismuto/química , Cerio/química , Lantano/química , Procesos Fotoquímicos , Compuestos Azo/química , Catálisis , Clorofenoles/química , Ciclohexanos/química , Emulsiones , Hexanoles/química , Calor , Luz , Mediciones Luminiscentes , Microscopía Electrónica de Transmisión , Octoxinol/química , Espectrofotometría Ultravioleta , Agua/química , Difracción de Rayos X
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