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1.
Environ Sci Pollut Res Int ; 30(21): 59660-59675, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37014596

RESUMEN

Electrolytic manganese residue (EMR) and red mud (RM) are solid waste by-products of the metal manganese and alumina industries, respectively. Under long-term open storage, ammonia nitrogen and soluble manganese ions in EMR and alkaline substances in RM severely pollute and harm the environment. In order to alleviate the pollution problem of EMR and RM. In this study, the alkaline substances in RM were used to treat ammonia nitrogen and soluble manganese ions in EMR. The results confirm the following suitable treatment conditions for the mutual treatment of EMR and RM: EMR-RM mass ratio = 1:1, liquid-solid ratio = 1.4:1, and stirring time = 320 min. Under these conditions, the elimination ratios of ammonia nitrogen (emitted in the form of ammonia gas) and soluble manganese ions (solidified in the form of Mn3.88O7(OH) and KMn8O16) are 85.87 and 86.63%, respectively. Moreover, the alkaline substances in RM are converted into neutral salts (Na2SO4 and Mg3O(CO3)2), achieving de-alkalinisation. The treatment method can also solidify the heavy metal ions-Cr3+, Cu2+, Ni2+, and Zn2+-present in the waste residue with leaching concentrations of 1.45 mg/L, 0.099 mg/L, 0.294 mg/L, and 0.449 mg/L, respectively. This satisfies the requirements of the Chinese standard GB5085.3-2007. In the mutual treatment of EMR and RM, the kinetics of ammonia nitrogen removal and manganese-ion solidification reactions are controlled via a combination of membrane diffusion and chemical reaction mechanisms.


Asunto(s)
Amoníaco , Electrólitos , Manganeso , Amoníaco/química , Electrólitos/química , Iones , Manganeso/química , Nitrógeno/química , Metalurgia
2.
J Environ Sci (China) ; 130: 14-23, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37032031

RESUMEN

The application of selenium nanoparticles (SeNPs) as nanofertilizers may lead to the release of SeNPs into aquatic systems. However, the environmental behavior of SeNPs is rarely studied. In this study, using alginate-coated SeNPs (Alg-SeNPs) and polyvinyl alcohol-coated SeNPs (PVA-SeNPs) as models, we systematically investigated the aggregation and stability of SeNPs under various water conditions. PVA-SeNPs were highly stable in mono- and polyvalent electrolytes, probably due to the strong steric hindrance of the capping agent. Alg-SeNPs only suffered from a limited increase in size, even at 2500 mmol/L NaCl and 200 mmol/L MgCl2, while they underwent apparent aggregation in CaCl2 and LaCl3 solutions. The binding of Ca2+ and La3+ with the guluronic acid part in alginate induced the formation of cross-linking aggregates. Natural organic matter enhanced the stability of Alg-SeNPs in monovalent electrolytes, while accelerated the attachment of Alg-SeNPs in polyvalent electrolytes, due to the cation bridge effects. The long-term stability of SeNPs in natural water showed that the aggregation sizes of Alg-SeNPs and PVA-SeNPs increased to several hundreds of nanometers or above 10 µm after 30 days, implying that SeNPs may be suspended in the water column or further settle down, depending on the surrounding water chemistry. The study may contribute to the deep insight into the fate and mobility of SeNPs in the aquatic environment. The varying fate of SeNPs in different natural waters also suggests that the risks of SeNPs to organisms living in diverse depths in the aquatic compartment should be concerned.


Asunto(s)
Nanopartículas , Selenio , Nanopartículas/química , Electrólitos/química , Alginatos , Agua
3.
Int J Mol Sci ; 23(24)2022 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-36555546

RESUMEN

In this study, we propose the use of artificial synaptic transistors with coplanar-gate structures fabricated on paper substrates comprising biocompatible and low-cost potato-starch electrolyte and indium-gallium-zinc oxide (IGZO) channels. The electrical double layer (EDL) gating effect of potato-starch electrolytes enabled the emulation of biological synaptic plasticity. Frequency dependence measurements of capacitance using a metal-insulator-metal capacitor configuration showed a 1.27 µF/cm2 at a frequency of 10 Hz. Therefore, strong capacitive coupling was confirmed within the potato-starch electrolyte/IGZO channel interface owing to EDL formation because of internal proton migration. An electrical characteristics evaluation of the potato-starch EDL transistors through transfer and output curve resulted in counterclockwise hysteresis caused by proton migration in the electrolyte; the hysteresis window linearly increased with maximum gate voltage. A synaptic functionality evaluation with single-spike excitatory post-synaptic current (EPSC), paired-pulse facilitation (PPF), and multi-spike EPSC resulted in mimicking short-term synaptic plasticity and signal transmission in the biological neural network. Further, channel conductance modulation by repetitive presynaptic stimuli, comprising potentiation and depression pulses, enabled stable modulation of synaptic weights, thereby validating the long-term plasticity. Finally, recognition simulations on the Modified National Institute of Standards and Technology (MNIST) handwritten digit database yielded a 92% recognition rate, thereby demonstrating the applicability of the proposed synaptic device to the neuromorphic system.


Asunto(s)
Solanum tuberosum , Óxido de Zinc , Protones , Transistores Electrónicos , Óxido de Zinc/química , Electrólitos/química
4.
J Phys Chem B ; 126(44): 9105-9122, 2022 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-36321420

RESUMEN

A wide range of systems, both engineered and natural, feature aqueous electrolyte solutions at interfaces. In this study, the structure and dynamics of water at the two prevalent crystallographic terminations of gamma-alumina, [110] and [100], and the influence of salts─sodium chloride, ammonium acetate, barium acetate, and barium nitrate on such properties─were investigated using equilibrium molecular dynamics simulations. The resulting interfacial phenomena were quantified from simulation trajectories via atomic density profiles, angle probability distributions, residence times, 2-D density distributions within the hydration layers, and hydrogen bond density profiles. Analysis and interpretation of the results are supported by simulation snapshots. Taken together, our results show stronger interaction and closer association of water with the [110] surface, compared to [100], while ion-induced disruption of interfacial water structure was more prevalent at the [100] surface. For the latter, a stronger association of cations is observed, namely sodium and ammonium, and ion adsorption appears determined by their size. The differences in surface-water interactions between the two terminations are linked to their respective surface features and distributions of surface groups, with atomistic-scale roughness of the [110] surface promoting closer association of interfacial water. The results highlight the fundamental role of surface characteristics in determining surface-water interactions, and the resulting effects on ion-surface and ion-water interactions. Since the two terminations of gamma-alumina considered represent interfaces of significance to numerous industrial applications, the results provide insights relevant for catalyst preparation and adsorption-based water treatment, among other applications.


Asunto(s)
Óxido de Aluminio , Simulación de Dinámica Molecular , Electrólitos/química , Iones/química , Cloruro de Sodio/química
5.
Environ Sci Pollut Res Int ; 29(50): 75955-75965, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35665892

RESUMEN

The photovoltaic investigation of novel and efficient dye-sensitized solar cells is discussed in this paper. Ruthenium-based synthetic dye (N3) is used as a sensitizer. A less toxic alternative is suggested for toxic indium-based glass substrates by using aluminum-doped zinc oxide (AZO) and fluorine-doped tin oxide (FTO) as charge collectors. Moreover, the electrolyte used is a mixture of polymer (polyaniline) and an iodide-triiodide couple to go for the approach involving a lower amount of iodine. In the paper study, on the extent of light, absorption of dye is done by ultraviolet-visible (UV-vis) spectroscopy. The morphological study of sheets is done using scanning electron microscopic (SEM) images to understand the binding of titania on photoanode. Photovoltaic characteristics (I-V) and induced photon to current efficiency (IPCE) measurements, and light harvesting efficiency (LHE) are also investigated. The highest power conversion efficiency of 6.18% is observed in the suggested fabricated green solar cell. Hence, more efficient, indium-free, and novel cell is fabricated by the usage of different charge collector substrates and quasi solid-state electrolytes.


Asunto(s)
Yodo , Rutenio , Energía Solar , Óxido de Zinc , Aluminio , Óxido de Aluminio , Colorantes/química , Electrólitos/química , Flúor , Yoduros , Polímeros , Rutenio/química , Óxido de Zinc/química
6.
Nat Chem ; 14(10): 1103-1109, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35710986

RESUMEN

Aqueous organic redox flow batteries offer a safe and potentially inexpensive solution to the problem of storing massive amounts of electricity produced from intermittent renewables. However, molecular decomposition represents a major barrier to commercialization-and although structural modifications can improve stability, it comes at the expense of synthetic cost and molecular weight. Now, utilizing 2,6-dihydroxy-anthraquinone (DHAQ) without further structural modification, we demonstrate that the regeneration of the original molecule after decomposition represents a viable route to achieve low-cost, long-lifetime aqueous organic redox flow batteries. We used in situ (online) NMR and electron paramagnetic resonance, and complementary electrochemical analyses to show that the decomposition compound 2,6-dihydroxy-anthrone (DHA) and its tautomer, 2,6-dihydroxy-anthranol (DHAL) can be recomposed to DHAQ electrochemically through two steps: oxidation of DHA(L)2- to the dimer (DHA)24- by one-electron transfer followed by oxidation of (DHA)24- to DHAQ2- by three-electron transfer per DHAQ molecule. This electrochemical regeneration process also rejuvenates the positive electrolyte-rebalancing the states of charge of both electrolytes without introducing extra ions.


Asunto(s)
Antralina , Mitoxantrona , Electrólitos/química , Iones , Oxidación-Reducción
7.
Biomed Res Int ; 2020: 8814878, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33274226

RESUMEN

According to the World Health Organization, the prevalence of cancer has increased worldwide. Oncological hyperthermia is a group of methods that overheat the malignant tissues locally or systematically. Nevertheless, hyperthermia is not widely accepted, primarily because of the lack of selectivity for cancer cells and because the temperature-triggered higher blood flow increases the nutrient supply to the tumor, raising the risk of metastases. These problems with classical hyperthermia led to the development of modulated electrohyperthermia (mEHT). The biophysical differences of the cancer cells and their healthy hosts allow for selective energy absorption on the membrane rafts of the plasma membrane of the tumor cells, triggering immunogenic cell death. Currently, this method is used in only 34 countries. The effectiveness of conventional oncotherapies increases when it is applied in combination with mEHT. In silico, in vitro, and in vivo preclinical research studies have all shown the extraordinary ability of mEHT to kill malignant cells. Clinical applications have improved the quality of life and the survival of patients. For these reasons, many other research studies are presently in progress worldwide. Thus, the objective of this review is to highlight the capabilities and advantages of mEHT and provide new hopes for cancer patients worldwide.


Asunto(s)
Electroquímica , Hipertermia Inducida , Neoplasias/terapia , Ensayos Clínicos como Asunto , Electrólitos/química , Humanos , Muerte Celular Inmunogénica
8.
Molecules ; 25(23)2020 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-33287431

RESUMEN

Research advances in electropolishing, with respect to the field of metalworking, have afforded significant improvements in the surface roughness and conductivity properties of aluminum polished surfaces in ways that machine polishing and simple chemical polishing cannot. The effects of a deep eutectic medium as an acid-free electrolyte were tested to determine the potential energy thresholds during electropolishing treatments based upon temperature, experiment duration, current, and voltage. Using voltammetry and chronoamperometry tests during electropolishing to supplement representative recordings via atomic force microscopy (AFM), surface morphology comparisons were performed regarding the electropolishing efficiency of phosphoric acid and acid-free ionic liquid treatments for aluminum. This eco-friendly solution produced polished surfaces superior to those surfaces treated with industry standard acid electrochemistry treatments of 1 M phosphoric acid. The roughness average of the as-received sample became 6.11 times smoother, improving from 159 nm to 26 nm when electropolished with the deep eutectic solvent. This result was accompanied by a mass loss of 0.039 g and a 7.2 µm change in step height along the edge of the electropolishing interface, whereas the acid treatment resulted in a slight improvement in surface roughness, becoming 1.63 times smoother with an average post-electropolishing roughness of 97.7 nm, yielding a mass loss of 0.0458 g and a step height of 8.1 µm.


Asunto(s)
Aluminio/química , Electroquímica/métodos , Electrólitos/química , Conductividad Eléctrica , Líquidos Iónicos/química , Ensayo de Materiales/métodos , Microscopía de Fuerza Atómica/métodos , Ácidos Fosfóricos/química , Solventes/química , Propiedades de Superficie , Temperatura
9.
Food Chem ; 309: 125789, 2020 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-31704073

RESUMEN

In this study, the development of an electroanalytical assay based on square wave voltammetry technique for determining sesamol (Ses) in sesame oil samples is described. The influence of various factors such as pH of the supporting electrolyte, its composition, and SW (square wave) parameters was studied. Linearity of the peak current depended on the concentration of Ses in the range from 3.0 to 140.0 µmol L-1 with a limit of detection of 0.71 µmol L-1. Furthermore, the cyclic voltammetric behavior of Ses and the effects of scan rate and pH on the peak current and peak potential of Ses were determined. Moreover, the electrode process was found to be diffusion-controlled. The proposed methodology was successfully applied for determining Ses in commercial sesame oil samples. The obtained results were in good agreement with the results from the HPLC-UV reference method.


Asunto(s)
Benzodioxoles/análisis , Fenoles/análisis , Potenciometría , Aceite de Sésamo/química , Carbono/química , Electrodos , Electrólitos/química , Concentración de Iones de Hidrógeno , Límite de Detección
10.
Chemosphere ; 239: 124730, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31726518

RESUMEN

The impact of electrolytes on the adsorption of emerging pollutants: pharmaceuticals onto layered materials: a raw clay mineral and its nonionic and cationic organoclay derivatives was studied. The selected pharmaceuticals: amoxicillin, norfloxacin, sulfamethoxazole, metoprolol, carbamazepine, and trimethoprim show different electric charges: zwitterionic, anionic, cationic and neutral and hydrophobic character (different LogP). Without any salts, the set of complementary data obtained by UV and infrared spectroscopies, X-ray diffraction points out the importance of the electric charge which represents a key parameter in both the spontaneity and feasibility of the adsorption. In contrast, the hydrophobicity of the analytes plays a minor role but determines the magnitude of the adsorbed amount of pharmaceuticals onto organoclays. With a dual hydrophilic and hydrophobic behavior, nonionic organoclay appears to be the most polyvalent material for the removal of the pharmaceuticals. In the presence of electrolytes (NaCl at a concentration of 1 × 10-2 mol L-1), both nonionic and cationic organoclays show a decrease of their efficiencies, whereas the adsorption is particularly enhanced for Na-Mt except for the cationic species (trimethoprim and metoprolol). Thus, in realistic experimental conditions close to those of natural effluents, raw clay mineral appears as the most appropriate sorbent for the studied pharmaceuticals while it raises the question of the usefulness of organoclays in water remediation strategy.


Asunto(s)
Electrólitos/química , Restauración y Remediación Ambiental/métodos , Preparaciones Farmacéuticas/análisis , Contaminantes del Suelo/análisis , Suelo/química , Contaminantes Químicos del Agua/análisis , Adsorción , Amoxicilina/análisis , Amoxicilina/química , Carbamazepina/análisis , Carbamazepina/química , Cationes/análisis , Interacciones Hidrofóbicas e Hidrofílicas , Metoprolol/análisis , Metoprolol/química , Norfloxacino/análisis , Norfloxacino/química , Preparaciones Farmacéuticas/química , Contaminantes del Suelo/química , Sulfametoxazol/análisis , Sulfametoxazol/química , Trimetoprim/análisis , Trimetoprim/química , Agua/química , Contaminantes Químicos del Agua/química , Difracción de Rayos X
11.
Mol Inform ; 38(10): e1900014, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31166649

RESUMEN

We report the building, validation and release of QSPR (Quantitative Structure Property Relationship) models aiming to guide the design of new solvents for the next generation of Li-ion batteries. The dataset compiled from the literature included oxidation potentials (Eox ), specific ionic conductivities (κ), melting points (Tm ) and boiling points (Tb ) for 103 electrolytes. Each of the resulting consensus models assembled 9-19 individual Support Vector Machine models built on different sets of ISIDA fragment descriptors.(1) They were implemented in the ISIDA/Predictor software. Developed models were used to screen a virtual library of 9965 esters and sulfones. The most promising compounds prioritized according to theoretically estimated properties were synthesized and experimentally tested.


Asunto(s)
Simulación por Computador , Evaluación Preclínica de Medicamentos , Electrólitos/química , Electrólitos/síntesis química , Solventes/química , Solventes/síntesis química , Conductividad Eléctrica , Suministros de Energía Eléctrica , Técnicas Electroquímicas , Electrólitos/análisis , Ésteres/síntesis química , Ésteres/química , Litio/química , Modelos Moleculares , Estructura Molecular , Relación Estructura-Actividad Cuantitativa , Programas Informáticos , Solventes/análisis , Sulfonas/síntesis química , Sulfonas/química , Máquina de Vectores de Soporte
12.
J Chromatogr A ; 1602: 474-480, 2019 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-31202495

RESUMEN

Evodiae Fructus is used as a traditional Chinese medicine for the treatment of several kinds of diseases with its bioactive constituents. In this study, a capillary electrochromatography-mass spectrometry (CEC-MS) method was developed to determine three bioactive compounds including evodiamine, rutaecarpine and limonin in Evodiae Fructus fruit. Home-developed monolithic columns with methyl-vinylimidazole functionalized organic polymer monolilth as stationary phases were used in CEC-MS with excellent separation selectivity and high efficiency. The CEC-MS methods provided 4-16 folds improvement of LODs when compared with CEC-UV method. The conditions, which could affect separation efficiency and detection sensitivity, were optimized. Under optimum conditions, baseline separation with high detection sensitivity was obtained. The method showed good linearity (R2 >0.99) of 0.8-160 µg mL-1 with low limits of detection of 0.15-0.31 µg mL-1. Relative standard deviations of migration time and relative peak areas were <13.89%. Recoveries of evodiamine, rutaecarpine and limonin in Evodiae Fructus fruit were tested and calculated, which ranged from 102% to 113%. Finally, the three bioactive compounds in Evodiae Fructus herb samples from different regions were analyzed and studied. It has been demonstrated that the developed method has great potential for quality control of Evodiae Fructus herb.


Asunto(s)
Electrocromatografía Capilar/métodos , Evodia/química , Imidazoles/química , Espectrometría de Masas/métodos , Polímeros/química , Acetonitrilos/química , Amoníaco/química , Calibración , Medicamentos Herbarios Chinos/química , Electrólitos/química , Frutas/química , Concentración de Iones de Hidrógeno , Alcaloides Indólicos/química , Límite de Detección , Limoninas/química , Quinazolinas/química , Estándares de Referencia , Reproducibilidad de los Resultados
13.
Bioelectrochemistry ; 128: 133-139, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30991309

RESUMEN

In addition to being environmentally friendly and ecologically acceptable, starch-based materials are inexpensive, readily available and renewable. The capability of starch, therefore, to inhibit the corrosion of Al-Mg-Si alloy processed via micro arc oxidation (MAO) process was investigated. For this aim, MAO coating was carried out on the present sample under AC conditions in an alkaline electrolyte with and without starch. The oxide layer formed on an Al-Mg-Si alloy created from electrolyte with starch was denser and thicker than that without starch. Whilst the oxide layer formed from electrolyte without starch was only composed of γ-Al2O3, the addition of starch into the electrolyte helped to decelerate the rate of cooling during the solidification of molten alumina, resulting in the formation of α-Al2O3 as well. Accordingly, the inhibiting action in the sample coated from the electrolyte containing starch was superior to that without starch.


Asunto(s)
Aleaciones/química , Aluminio/química , Corrosión , Electrólitos/química , Magnesio/química , Silicio/química , Almidón/química , Óxido de Aluminio/química , Oxidación-Reducción , Porosidad , Propiedades de Superficie , Difracción de Rayos X
14.
J Oleo Sci ; 68(4): 311-320, 2019 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-30867393

RESUMEN

The solubility of H2 in electrolytes, H2 reaction consumption and the conductivity of electrolytes under different pressures in an electrochemical hydrogenation reactor were studied. It was found that with an increase in H2 pressure, H2 was electrolyzed at the anode, accompanied by the generation of H+. The solubility of H2 in the electrolytes and the conductivity of the electrolytes also increased. At first, the reaction consumption increased, followed by a tendency to be stable at 3 MPa. Therefore, the electrochemical hydrogenation of soybean oil was carried out at a H2 pressure of 3 MPa. When the current was 120 mA, the temperature was 50°C, the agitation speed was 300 rpm, and the time was 7.5 h, the IV of hydrogenated soybean oil was 99.6 g I2/100 g oil, and the TFA content of the oil was 4.3%.


Asunto(s)
Técnicas Electroquímicas/métodos , Hidrógeno/química , Aceite de Soja/química , Electroquímica , Electrólitos/química , Hidrogenación , Presión , Solubilidad , Temperatura
15.
J Chromatogr Sci ; 56(8): 746-752, 2018 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-29750262

RESUMEN

A precise, accurate, selective and sensitive capillary electrophoresis method using a diode array detector was developed for the first time for the determination of both scutellarein (SLN) and caffeic acid (CAA) in prepared Abelia triflora extract. Electrophoretic analysis was performed using a background electrolyte solution consisting of borax buffer (40 mM, pH 9.2) and a 200-nm detection wavelength. This method was fully validated according to The International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) guidelines. The method was linear in the concentration range 2.5-100 µg/mL and it allowed the determination of both compounds with high degree of recovery (%Er < 2%) and intra-day and inter-day precision (relative standard deviation values <2%) and method robustness was also assessed by the low values of %RSD < 2% obtained after small deliberate changes in the method parameters. The contents of SLN and CAA were calculated using both the external standard and standard addition methods. Analysis of the ethyl acetate fraction of A. triflora revealed that SLN and CAA were found in concentrations of 0.46 mg/g and 2.10 mg/g, respectively, in the ethyl acetate fraction and 0.29 and 1.32 mg%, respectively, in the dry plant leaves.


Asunto(s)
Apigenina/análisis , Ácidos Cafeicos/análisis , Caprifoliaceae/química , Electroforesis Capilar/métodos , Extractos Vegetales/química , Acetatos/química , Boratos/química , Tampones (Química) , Electrólitos/química
16.
Sci Rep ; 8(1): 7875, 2018 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-29777196

RESUMEN

Pollen tubes are used as models in studies on the type of tip-growth in plants. They are an example of polarised and rapid growth because pollen tubes are able to quickly invade the flower pistil in order to accomplish fertilisation. How different ionic fluxes are perceived, processed or generated in the pollen tube is still not satisfactorily understood. In order to measure the H+, K+, Ca2+ and Cl- fluxes of a single pollen tube, we developed an Electrical Lab on a Photovoltaic-Chip (ELoPvC) on which the evolving cell was immersed in an electrolyte of a germination medium. Pollen from Hyacinthus orientalis L. was investigated ex vivo. We observed that the growing cell changed the (redox) potential in the medium in a periodic manner. This subtle measurement was feasible due to the effects that were taking place at the semiconductor-liquid interface. The experiment confirmed the existence of the ionic oscillations that accompany the periodic extension of pollen tubes, thereby providing - in a single run - the complete discrete frequency spectrum and phase relationships of the ion gradients and fluxes, while all of the metabolic and enzymatic functions of the cell life cycle were preserved. Furthermore, the global 1/fα characteristic of the power spectral density, which corresponds to the membrane channel noise, was found.


Asunto(s)
Electrólitos/análisis , Hyacinthus/metabolismo , Polen/química , Semiconductores , Calcio/química , Calcio/metabolismo , Cloruros/química , Cloruros/metabolismo , Electrólitos/química , Electrólitos/metabolismo , Germinación , Iones/metabolismo , Dispositivos Laboratorio en un Chip , Oxidación-Reducción , Polen/crecimiento & desarrollo , Polen/metabolismo , Tubo Polínico/química , Tubo Polínico/metabolismo , Potasio/química , Potasio/metabolismo
17.
J Phys Chem B ; 122(14): 3974-3987, 2018 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-29513995

RESUMEN

Ibuprofen (IBF), 2-(4-isobutylphenyl) propionic acid, is a surface-active, common nonsteroidal anti-inflammatory drug (NSAID), and it possesses a high critical micelle concentration (cmc) compared to that of conventional surfactants. The interactions of this common NSAID with an anionic surfactant, sodium octyl sulfosuccinate, were studied by tensiometric, fluorimetric, and calorimetric measurements to investigate this system as a possible model drug-delivery system for an NSAID like IBF, particularly in a high-dose regime for IBF. The interactions between the drug and the surfactant were modeled using a regular solution theory approach in the presence and absence of a model electrolyte (sodium iodide) and a novel nonaromatic, gemini hydrotrope, tetramethylene-1,4-bis( N, N-dimethyl- N-butylammonium)bromide (4-4-4). Both the simple and the hydrotropic electrolyte were shown to have an effect on the solution properties (aggregation parameters, interfacial properties, and thermodynamics of aggregate formation) of the drug-surfactant mixtures and on the interaction between the drug and the surfactant. Surface charges of all self-assembled systems were estimated from ζ-potential measurements, whereas density functional theory calculations showed the interaction energy comparison among all of the binary and ternary combinations. All of these results were interpreted in terms of how altering the subtle balance of hydrophobic and electrostatic forces can significantly improve the ability of these self-assembled systems to transport drug molecules.


Asunto(s)
Antiinflamatorios no Esteroideos/química , Sistemas de Liberación de Medicamentos , Ibuprofeno/química , Compuestos de Amonio Cuaternario/química , Yoduro de Sodio/química , Succinatos/química , Tensoactivos/química , Aniones/química , Antiinflamatorios no Esteroideos/administración & dosificación , Electrólitos/química , Ibuprofeno/administración & dosificación , Termodinámica
18.
Nutrients ; 10(2)2018 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-29443921

RESUMEN

There are no compatibility studies for neonatal parenteral nutrition solutions without cysteine containing calcium chloride or calcium gluconate using light obscuration as recommended by the United States Pharmacopeia (USP). The purpose of this study was to do compatibility testing for solutions containing calcium chloride and calcium gluconate without cysteine. Solutions of TrophAmine and Premasol (2.5% amino acids), containing calcium chloride or calcium gluconate were compounded without cysteine. Solutions were analyzed for particle counts using light obscuration. Maximum concentrations tested were 15 mmol/L of calcium and 12.5 mmol/L of phosphate. If the average particle count of three replicates exceeded USP guidelines, the solution was determined to be incompatible. This study found that 12.5 and 10 mmol/L of calcium and phosphate, respectively, are compatible in neonatal parenteral nutrition solutions compounded with 2.5% amino acids of either TrophAmine or Premasol. There did not appear to be significant differences in compatibility for solutions containing TrophAmine or Premasol when solutions were compounded with either CaCl2 or CaGlu-Pl. This study presents data in order to evaluate options for adding calcium and phosphate to neonatal parenteral nutrition solutions during shortages of calcium and cysteine.


Asunto(s)
Cloruro de Calcio/análisis , Gluconato de Calcio/análisis , Composición de Medicamentos , Incompatibilidad de Medicamentos , Fenómenos Fisiológicos Nutricionales del Lactante , Soluciones para Nutrición Parenteral/química , Aminoácidos/química , Aminoácidos/normas , Dispersión Dinámica de Luz , Electrólitos/química , Electrólitos/normas , Glucosa/química , Glucosa/normas , Humanos , Concentración de Iones de Hidrógeno , Recién Nacido , Rayos Láser , Concentración Osmolar , Soluciones para Nutrición Parenteral/normas , Farmacopeas como Asunto , Fosfatos/química , Compuestos de Potasio/química , Soluciones/química , Soluciones/normas , Estados Unidos
19.
Chem Soc Rev ; 47(6): 2065-2129, 2018 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-29399689

RESUMEN

Flexible solid-state supercapacitors (FSSCs) are frontrunners in energy storage device technology and have attracted extensive attention owing to recent significant breakthroughs in modern wearable electronics. In this study, we review the state-of-the-art advancements in FSSCs to provide new insights on mechanisms, emerging electrode materials, flexible gel electrolytes and novel cell designs. The review begins with a brief introduction on the fundamental understanding of charge storage mechanisms based on the structural properties of electrode materials. The next sections briefly summarise the latest progress in flexible electrodes (i.e., freestanding and substrate-supported, including textile, paper, metal foil/wire and polymer-based substrates) and flexible gel electrolytes (i.e., aqueous, organic, ionic liquids and redox-active gels). Subsequently, a comprehensive summary of FSSC cell designs introduces some emerging electrode materials, including MXenes, metal nitrides, metal-organic frameworks (MOFs), polyoxometalates (POMs) and black phosphorus. Some potential practical applications, such as the development of piezoelectric, photo-, shape-memory, self-healing, electrochromic and integrated sensor-supercapacitors are also discussed. The final section highlights current challenges and future perspectives on research in this thriving field.


Asunto(s)
Capacidad Eléctrica , Dispositivos Electrónicos Vestibles , Electrodos , Electrólitos/química , Geles/química , Estructuras Metalorgánicas/química , Fósforo/química , Compuestos de Tungsteno/química
20.
J Mech Behav Biomed Mater ; 77: 347-352, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28965041

RESUMEN

Niobium plates were electrochemically treated by Plasma Electrolytic Oxidation (PEO) with electrolytes containing phosphorous and/or calcium. Three different electrolyte and experimental parameters were used forming three different surfaces. Film morphology, thickness, and chemical composition were analyzed by scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). A profilometer and the sessile drop technique measured the average surfaces roughness (Ra) and contact angles respectively. X-ray diffraction technique (XRD) analyzed the oxide crystallinity, and scratch tests evaluated the film adhesion. All oxidized surfaces presented pores, without observed cracks. Comparing the different experimental conditions, films obtained with phosphoric acid (P100) show superficial pores, phosphorus incorporation, high hydrophilicity, non-crystalline oxide formation, and good scratch resistance. Films treated with calcium acetate electrolyte (Ca100), compared to P100 exhibit smaller size pores and film thickness, smaller hydrophilicity, and lower scratch resistance. They also demonstrated higher oxide crystallinity, calcium incorporation, and pores interconnections. When the PEO was executed with a blended electrolyte containing calcium acetate and phosphoric acid (Ca50P50) the formed films presented the highest thickness, high phosphorus incorporation, and the lowest contact angle compared with other films. In addition, the pores size, the scratch resistance, calcium incorporation, and oxide crystallinity present intermediate values compared to P100 and Ca100 films. Film crystallinity seems to be influenced by calcium incorporation, whereas, hydrophilicity is phosphorus amount dependent. The pores amount and their interconnections reduced the scratch resistance. Surface features obtained in this work are largely mentioned as positive characteristics for osseointegration processes.


Asunto(s)
Calcio/química , Niobio/química , Oxígeno/química , Fósforo/química , Materiales Biocompatibles/química , Electrólitos/química , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Oseointegración , Oxidación-Reducción , Óxidos/química , Ácidos Fosfóricos/química , Propiedades de Superficie , Titanio/química , Difracción de Rayos X
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