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1.
Carbohydr Polym ; 280: 119018, 2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-35027123

RESUMEN

Conductive hydrogels have the mechanical properties and the electronic transport properties of conductive polymers, which have been widely used in the fields of energy storage and bioelectronics. However, the rigidity and brittleness of conductive polymers hinder the long-term stability of hydrogels and limit its application in new flexible electronic devices. It is a high challenging task to prepare ion-conductive hydrogels with excellent mechanical properties, anti-freeze and electrical conductivity through a simple preparation process under the action of hydrogen bonds. We present a facile strategy to prepare mechanically tough, swelling ability hydrogels reinforced by cellulose nanocrystals (CNCs). Herein, CNCs were produced by high pressure homogeneous and pretreated with deep eutectic solvent (DES). The conductivity of the hydrogel is 0.021 S/cm at room temperature. Due to the function of DMSO/H2O in organic solvent system, the ion-conducting hydrogel remains flexible and conductive (0.014 S/cm) at -70 °C. Hydrogel has excellent mechanical properties (stress about 1.4 MPa, strain about 1018%), excellent transparency, freezing resistance (-70 °C) and other comprehensive characteristics. The hydrogel can be assembled into a sensor for use in monitoring large and small movements of the human body, showing good responsiveness and stability.


Asunto(s)
Celulosa/química , Conductividad Eléctrica , Hidrogeles , Nanopartículas , Dispositivos Electrónicos Vestibles , Congelación , Humanos , Enlace de Hidrógeno , Fenómenos Mecánicos , Movimiento , Polímeros/química , Cloruro de Sodio/química , Resistencia a la Tracción
2.
ChemSusChem ; 15(13): e202101889, 2022 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-34730878

RESUMEN

5-Hydroxymethylfurfural (HMF) has been regarded as an essential building block for synthesizing chemicals and biofuels, but the direct conversion of biomass to HMF is still a critical challenge. In this study, a cheap and green aqueous-natural deep eutectic solvent (A-NADES) was used to efficiently produce HMF from various carbohydrates, with a low amount of SnCl4 as the catalyst. High HMF yields of 64.3, 64.0, 61.3, and 54.5 % were obtained from glucose, starch, rice waste, and bread waste at 130 °C in the A-NADES/MIBK (methyl isobutyl ketone) biphasic system, respectively. Mechanistic study results revealed that the water in A-NADES was the key factor in facilitating the conversion of Sn atom existent forms and promoted the HMF production. The choline chloride in NADES stabilized the HMF product with the cooperation of extraction solvent MIBK and inhibited the side reactions of HMF. This study investigated the multiple interaction functions of A-NADES to feedstocks and proposed a practical application of novel solvents to facilitate biomass and food waste conversion with a green method.


Asunto(s)
Eliminación de Residuos , Almidón , Disolventes Eutécticos Profundos , Alimentos , Furaldehído/análogos & derivados , Glucosa , Solventes , Agua
3.
ChemSusChem ; 13(3): 640-646, 2020 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-31758660

RESUMEN

Herein, a synthetic pathway to renewable phthalic anhydride (PA) from 5-hydroxymethfurfural (HMF) in one pot is reported. The commonly available catalysts MoO3 and Cu(NO3 )2 play a crucial role in integrating the multiple steps of the reaction, namely decarbonylation of HMF to active furyl intermediate (AFI), oxidation of HMF to maleic anhydride (MA), Diels-Alder cycloaddition of AFI and MA, and subsequent dehydration, in one pot. Under mild reaction conditions, a 63.2 % yield of PA is obtained from HMF. Compared with the currently reported route to renewable PA based on the Diels-Alder cycloaddition of biomass-derived MA and furan, this convenient one-pot synthesis represents a great improvement in efficiency.

4.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(3): 652-656, 2019 Jun.
Artículo en Chino | MEDLINE | ID: mdl-31204913

RESUMEN

OBJECTIVE: To analyze the 5 experimental indexes of CDSS in the patients with acute leukemia (AL) so as to provide the laboratorial basis for the early diagnosis and treatment of the secondary DIC in AL. METHODS: Three hundred and thirty three patients with AL were divided into 7 groups, such as AML-M1-M5, other AML and ALL. The experimental indexes and CDSS scores of all AL groups were compared and analyzed in pairs, meanwhile 100 healthy persons were taken in the control group. Clinical events such as early death in all cases were also analyzed. RESULTS: The highest positive rate of Platelet was 59.76%, among the 5 experimental indexes, followed by D-D (30.93%), and the lowest APTT with only 2.70%. Compared with the control group, the differences of remaining indexes were statistically significant (P<0.01), except APTT in group AML-M3 and FIB in the other AML groups. The score of laboratory index was (1.50±1.51) in all AL patients, and the positive rate of overt DIC ( score≥4) was 14.11% ( 47 cases). The highest score of CDSS was (3.34 ±1.71) in group AML-M3. The difference in the incidence of early death and cerebral (pulmonary) hemorrhage in DIC patients were statistically significant (P<0.05 and P<0.01). CONCLUSION: The application of quantitative integral method of experimental indexes in CDSS is objective and feasible, which is of great significance for early diagnosis and early treatment of acute leukemia complicated with DIC.


Asunto(s)
Coagulación Intravascular Diseminada , Leucemia Mieloide Aguda , Leucemia Promielocítica Aguda , Enfermedad Aguda , Hemorragia , Humanos
5.
ChemSusChem ; 10(13): 2696-2706, 2017 07 10.
Artículo en Inglés | MEDLINE | ID: mdl-28425225

RESUMEN

The scientific community has been seeking cost-competitive and green solvents with good dissolving capacity for the valorization of lignocellulosic biomass. At this point, deep eutectic solvents (DESs) are currently emerging as a new class of promising solvents that are generally liquid eutectic mixtures formed by self-association (or hydrogen-bonding interaction) of two or three components. DESs are attractive solvents for the fractionation (or pretreatment) of lignocellulose and the valorization of lignin, owing to the high solubility of lignin in DESs. DESs are also employed as effective media for the modification of cellulose to afford functionalized cellulosic materials, such as cellulose nanocrystals. More interestingly, biomassderived carbohydrates, such as fructose, can be used as one of the constituents of DESs and then dehydrated to 5-hydroxymethylfurfural in high yield. In this review, a comprehensive summary of recent contribution of DESs to the processing of lignocellulosic biomass and its derivatives is provided. Moreover, further discussion about the challenges of the application of DESs in biomass processing is presented.


Asunto(s)
Biomasa , Tecnología Química Verde/métodos , Lignina/química , Solventes/química , Catálisis , Lignina/aislamiento & purificación
6.
Chem Commun (Camb) ; 51(91): 16320-3, 2015 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-26403664

RESUMEN

γ-Valerolactone (GVL), a versatile biomass derived platform molecule, was synthesized with a highest yield of 89.8% from methyl levulinate (ML) using self-supplied H2 coming from the decomposition of MeOH derived partially from ML. Cu-Cr acted as a bi-functional catalyst for both H2 production from MeOH and carbonyl hydrogenation. An extremely low amount of MeOH (29 mol% relative to ML) was initially necessary to start up the hydrocyclization of ML to GVL and MeOH, which is in turn employed as an in situ H2 source for ML hydrogenation, providing an atom-economical pathway for GVL production.


Asunto(s)
Técnicas de Química Sintética , Hidrógeno/química , Lactonas/síntesis química , Metanol/química , Catálisis , Cromo , Cobre , Ácidos Levulínicos/química
7.
Bioorg Med Chem ; 20(14): 4405-12, 2012 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-22698782

RESUMEN

A novel series of N-aryl salicylamides with a hydroxamic acid moiety at 5-position were synthesized efficiently. Their activities against EGFR kinase and HDACs were evaluated. All compounds displayed inhibitory activity against EGFR and HDACs. The antiproliferative activities of synthesized compounds were evaluated by MTT method against human cancer cell lines A431, A549 and HL-60. Compound 1o showed the most potent inhibitory activity against A431 and A549. Compounds 1k and 1n exhibited higher potency against HL-60 than gefitinib and SAHA. N-Aryl salicylamides with a hydroxamic acid moiety at 5-position is another new HDAC-EGFR dual inhibitors.


Asunto(s)
Receptores ErbB/antagonistas & inhibidores , Inhibidores de Histona Desacetilasas/síntesis química , Histona Desacetilasas/química , Ácidos Hidroxámicos/química , Inhibidores de Proteínas Quinasas/síntesis química , Salicilamidas/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Receptores ErbB/metabolismo , Células HL-60 , Inhibidores de Histona Desacetilasas/química , Inhibidores de Histona Desacetilasas/toxicidad , Histona Desacetilasas/metabolismo , Humanos , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/toxicidad , Salicilamidas/síntesis química , Salicilamidas/toxicidad , Relación Estructura-Actividad
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