BIOCATALYSIS AND BIOTRANSFORMATION
·
2016
·
IF 0.892
Wei Wei,Danping Qi,Mingming Diao,Lu Zhaoxin,Fengxia Lv,Haizhen Zhao
In this study, the synthesis of 3-O-β-D-galactopyranosyl-sn-glycerol (GG) was performed by the reverse hydrolysis of D-galactose and glycerol using β-galactosidase from Kluyveromyces lactis. Four process variables, reaction temperature (30.0–45.0 °C), reaction time (24–48 h), enzyme concentration (150.00–350.00 U/mL), and substrate molar ratio (glycerol:D-galactose, 7.5:12.5 mmol/mmol) were investigated and optimized via response surface methodology (RSM) for optimal GG synthesis. Both quadratic equations and the optimal reaction conditions were established. Results showed that the four variables, i.e., reaction temperature, reaction time, enzyme concentration, and substrate molar ratio had significant (p < 0.0001) effects on the synthesis of GG. The optimal reaction conditions were identified as 350.00 U/mL of β-galactosidase concentration and 8.65:1.00 of substrate molar concentration ratio (glycerol: D-galactose) at 39.8 °C and 48 h of reaction. Under these conditions, the GG concentration was 140.03 g/L and GG yield was 55.71%, which both were close to the predicted values (143.26 g/L and 56.73%). This finding proves the RSM to be a useful tool in optimizing process conditions for GG synthesis.
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2017
·
IF 3.582
Xue Tian,Shuang Wang,Jinsheng Li,Fengxiang Liu,Xu Wang,Hao Chen,Hongzhe Ni,Zhe Wang
Polybenzimidazole (PBI)/ionic liquid (IL) functional Si–O–Si network composite membranes are prepared from PBI with 1-(3-trimethoxysilylpropyl)-3-methylimidazolium chloride. The IL can be hydrolyzed to form Si–O–Si network structure under acidic conditions. And such IL functional Si–O–Si network (NP) in the composite membranes could improve phosphoric acid doping levels and proton conductivities simultaneously. The ability of retaining more PA is also reflected in the high proton conductivity value of PBI/NP-15% membrane which shows almost three-fold increment compared to the pristine PBI. All the PBI/NP-X composite membranes display excellent chemical stability and improved mechanical strength . This is attributed to Si–O–Si network structure. Moreover, PBI/NP composite membranes have demonstrated high thermal stability up to 250 °C, which is attractive for high-temperature (>200 °C) proton exchange membrane fuel cells.
✓ 已验证
产品关联
DOI
高影响因子
BIOCATALYSIS AND BIOTRANSFORMATION
·
2016
·
IF 0.892
Danping Qi,Wei Wei,Mingming Diao,Fengxia Lv,Zhaoxin Lu,Xiaomei Bie,Haizhen Zhao
Lipase-catalyzed synthesis of mono- and diesters of 3-O-β-D-galactopyranosyl-sn- glycerol (β-GG) with caproic acid was performed in acetone. The simultaneous production of 1(6’)-monoesters and 1,6’-diesters of β-GG was achieved in this reaction. In order to improve the yield of β-GG esters, four process parameters, enzyme concentration (15 ∼ 25 mg/mL), and substrate molar ratio (caproic acid: β-GG= 1.60 ∼ 2.00 mmol: 0.10 mmol), reaction temperature (40 ∼ 60 °C), and reaction time (8 ∼ 12 h), were optimized via response surface methodology (RSM) employing a three-level-four-variable central composite design. Results showed that enzyme concentration had the most significant (p < 0.0001) effect on the synthesis of β-GG esters. The optimal reaction conditions in acetone were given as follows: Novozyme435 concentration 18.65 mg/mL, molar rate of caproic acid to β-GG 19.46:1, reaction temperature 48 °C, and reaction time 9.83 h. The yield of β-GG esters reached 88.08% under above optimized conditions, which was very close to the predicted value 87.95%. The molar ratio of monoester to diesters was 0.39:0.61. β-GG esters with other fatty acyl chains were synthesized based on the optimized conditions. In vitro antitumor activity indicated that the antitumor activity of β-GG esters was dependent on the nature of fatty acids, such as the length of acyl chain, the degree of saturation, as well as the number of acyl chain.
✓ 已验证
产品关联
DOI
高影响因子
Scientific Reports
·
2016
·Vol. 6
·期 1
·1-12
·
IF 5.228
Xie Yinghao,Wu Fangfang,Sun Xiaoqin,Chen Hongmei,Lv Meilin,Ni Shuang,Liu Gang,Xu Xiaoxiang
Wurtzite solid solutions between GaN and ZnO highlight an intriguing paradigm for water splitting into hydrogen and oxygen using solar energy. However, large composition discrepancy often occurs inside the compound owing to the volatile nature of Zn, thereby prescribing rigorous terms on synthetic conditions. Here we demonstrate the merits of constituting quinary Zn-Ga-Ge-N-O solid solutions by introducing Ge into the wurtzite framework. The presence of Ge not only mitigates the vaporization of Zn but also strongly promotes particle crystallization. Synthetic details for these quinary compounds were systematically explored and their photocatalytic properties were thoroughly investigated. Proper starting molar ratios of Zn/Ga/Ge are of primary importance for single phase formation, high particle crystallinity and good photocatalytic performance. Efficient photocatalytic hydrogen and oxygen production from water were achieved for these quinary solid solutions which is strongly correlated with Ge content in the structure. Apparent quantum efficiency for optimized sample approaches 1.01% for hydrogen production and 1.14% for oxygen production. Theoretical calculation reveals the critical role of Zn for the band gap reduction in these solid solutions and their superior photocatalytic acitivity can be understood by the preservation of Zn in the structure as well as a good crystallinity after introducing Ge.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Analytical Methods
·
2013
·Vol. 5
·期 6
·1469-1473
·
IF 1.855
Dan Wu,He Li,Xiaodong Xue,Haixia Fan,Qiang Xin,Qin Wei
A sensitive and selective sensor was developed for dopamine (DA) determination based on a molecularly imprinted electropolymer of o-phenylenediamine (OPD). A very small quantity of biocompatible sulfonated graphene was modified onto Au electrode to enhance the current response. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were employed to characterize the molecular imprinted (MIP) sensor. Several important parameters controlling the performance of the molecularly imprinted sensor were investigated and optimized. Under optimum condition, DA can be determined in the range of 0.5–7.0 mg L−1 and the low detection limit is 0.11 mg L−1. Ascorbic acid (AA) almost did not interfere in the determination of DA when the concentration molar ratio of 50 : 1. The prepared sensor had been applied to the analysis of DA in human serum samples with satisfactory results. It also showed stable reproducibility and can be easily fabricated at low cost.
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF PHARMACEUTICS
·
2013
·
IF 3.458
Hejian Guo,Dianrui Zhang,Caiyun Li,Lejiao Jia,Guangpu Liu,Leilei Hao,Dandan Zheng,Jingyi Shen,Tingting Li,Yuanyuan Guo,Qiang Zhang
A novel polymer, i.e. galactosylated O-carboxymethyl chitosan-graft-stearic acid (Gal-OCMC-g-SA) was synthesized for liver targeting delivery of doxorubicin . The chemical structure was characterized by FT-IR, 1 H NMR and elemental analysis. Gal-OCMC-g-SA could self-assemble into nanoparticles with diameter of 160 nm by probe sonication in aqueous medium and exhibited a low critical aggregation concentration of 0.047 mg/mL. The DOX-loaded Gal-OCMC-g-SA (Gal-OCMC-g-SA/DOX) self-assembled nanoparticles were almost spherical in shape with an average diameter of less than 200 nm and zeta potential of around −10 mV. In vitro release revealed that the Gal-OCMC-g-SA/DOX nanoparticles exhibited a sustained and pH-dependent drug release manner. Furthermore, the hemolysis test demonstrated the good safety of Gal-OCMC-g-SA in blood-contacting applications. These results indicated that Gal-OCMC-g-SA/DOX nanoparticles were highly potential to be applied in cancer therapy.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2015
·
IF 1.098
Yiyang Kong,Binjie Hu,Yanqing Guo,Yifan Wu
Room temperature ionic liquids (RTILs) are non-volatile organic salts. They may replace conventional coalescing agents in latex coating thus reducing volatile organic compounds (VOCs) emission as well as improving performance of latex coating products such as better thermal stability, conductivity, and antifouling property. The formation of latex coating containing RTILs can be achieved by encapsulation of RTILs inside particles via miniemulsion polymerization. In this study, the role of RTILs and its concentration on stability of miniemulsion during storage and polymerization were investigated. It has been found that, above a critical concentration (10 wt%), adding more RTILs to oil phase may weaken miniemulsion stability during storage as well as polymerization. Such observations were consistent with the zeta potential measurement for miniemulsions prepared at the similar conditions. The results obtained here would be a useful guideline for the development of new waterborne coating products with desirable functions and particle sizes.
✓ 已验证
产品关联
DOI
高影响因子
AICHE JOURNAL
·
2024
·
IF 3.5
Xin Zhao,Ruiqi Fang,Fengliang Wang,Yingwei Li
Here, we report the fabrication of atomic-metal catalysts for the facile cascaded transformation of lignin β-O-4 dimeric model compound into quinoline. A series of dual-metal single-atom (SA) moieties (MaC 4 and Mb 2 N 6 , where Ma and Mb represent two different metal SAs, C and N represent carbon and nitrogen atoms, respectively) are integrated on N-doped carbons with designed compositions and coordination configurations. Characterizations indicate the homogeneous distribution of uniform and modifiable SA sites, over which the electron distribution is significantly polarized due to synergistic interactions. The distinctive physicochemical properties of catalysts afford attractive performances in the cascaded synthesis of quinoline from lignin β-O-4 dimeric model compound through cascaded transformation. In a continuous flow instrument, CuC 4 /Co 2 N 6 @NC furnishes 93.7% yield of 2-phenylquinoline with a space-time yield of 75.7 g g cat h −1 . Control experiments and density functional theory calculations reveal the synergistic interactions between CuC 4 and Co 2 N 6 endow the catalyst with high efficiency in cascaded transformation.
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Hongping Li,Tianxiao Zhu,Yuan Zhang,Jie Yin,Jinrui Zhang,Linhua Zhu,Hua Wei,Huaming Li
Adsorbents with high adsorption capacity and selectivity have long been the pursuit of researchers in the field of adsorptive desulfurization. In this study, a novel single-atom adsorbent comprised of iron (Fe) integrated into C, O co-doped hexagonal boron nitride (Fe-BNCO) has been successfully synthesized. This unique material demonstrates outstanding adsorption capabilities, boasting an adsorption capacity of 49.7 mg S/g and excellent selectivity for adsorptive desulfurization. Notably, this adsorption capacity is 48.6 % higher than that of pure BNCO. The incorporation of the Fe element into boron nitride materials induces a reduction in crystallinity and an increase in specific surface area, resulting in a higher number of available adsorption sites. Combining experimental analysis with theoretical calculations, we propose that the exceptional adsorption performance of Fe-BNCO can be attributed to the formation of S-Fe coordination interaction, while maintaining the existing π-π interactions. This study advances our understanding of adsorbents with high adsorption capacity and selectivity, providing valuable insights for the field of adsorptive desulfurization.
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Fuxin Liang,Yulin Wei,Yuhang Du,Fan Yang,Zhe Pang,Junyan Wu,Sai Huang,Honglei Wang,Qinggang Li,Chao Wu,Guopu Shi
This study investigated the catalytic hydrogenation of ethyl nicotinate using Pd/Al 2 O 3 -SiO 2 foam ceramic catalysts prepared via sol-gel impregnation (SI), sol-gel precipitation (SP), precipitation-impregnation (PI), and co-precipitation (CP). We aimed to evaluate the performance and stability of these catalysts as coatings on foam ceramic surfaces in a high-pressure hydrogen reactor at 403 K and 5 MPa. Various physicochemical characterization methods were employed to correlate catalytic performance with physicochemical properties. Results indicated that sol-gel prepared supports had higher specific surface areas, more acidic sites, and better metal-carrier interactions compared to the precipitation method. SEM analyses revealed flatter and smoother coatings from the sol-gel method, while TEM showed uniform Pd distribution with impregnation. Ultimately, the SI method provided the best catalytic performance with a conversion of 86.77 %. The conversion of the substrate remained above 80 % after five cycles.
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Wei Gao,Zhenyu Wang,Yongzheng Zhang,Chunyin Shen,Yanli Wang,Liang Zhan
Phenolic aerogels have addressed considerate application in fabricating lightweight ablative materials owing to their excellent characteristics of large surface area, low bulk density, and low thermal conductivity . However, unsatisfactory thermal stability still limits their extensive applications. To enhance the thermal stability, we reported a facile co-precursor strategy to prepare boron-modified phenolic aerogels, through sol–gel polymerization of phenylboronic acid and phenolic resin. The thermal stability of hybrid aerogels is remarkably enhanced, achieving a char yield of up to 64.16 % at 850 ℃ due to the much higher bonding energy of B-O bonds. The phenyl-borates structure gradually transferred into B 2 O 3 , effectively fixing the oxygen content and reducing the carbon loss during the carbonization process. Moreover, the in-situ formed phenyl-borates structure contributes to forming a denser network, which affords the hybrid aerogels with diverse properties: low density (0.31–0.34 g/cm 3 ), a hierarchical micro- meso -macro porous structure with small particle size (28.42–48.58 nm), promoted compressive strength (20.65–28.46 MPa), and excellent insulation performance (0.0406–0.0564 W/(m•k)). These integrated superiorities enable the boron-modified phenolic aerogels to perform effectively in thermal insulation fields, especially for aerospace related industry.
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Qiujiang Li,Xuanyu Xiao,Tianyou Yan,Dan Song,Lei Li,Zhiyu Chen,Yuting Zhong,Wei Deng,Xiaoyan Liu,Yueming Song,Lei Wang,Yunbing Wang
The complex microenvironment of persistent inflammation and bacterial infection is a major challenge in chronic diabetic wounds. The development of nanozymes capable of efficiently scavenging reactive oxygen species (ROS) is a promising method to promote diabetic wound healing. However, many nanozymes show rather limited antioxidant activity and ROS-dependent antibacterial effects under certain circumstances, further weakening their ability to scavenge ROS. To meet these challenges, electronically regulated bioheterojunction (E-bio-HJ) nanozyme hydrogels derived from metal–organic frameworks (MOFs) were designed and prepared via an interface engineering strategy. Owing to the electron transfer and redistribution effects of the abundant and highly dispersed Cu–O–Zn sites at the heterogeneous interface, the E-bio-HJ nanozymes exhibited catalase (CAT)-like activity with ultrahigh hydrogen peroxide affinity (Km = 25.76 mM) and sustained ROS consumption. In addition, owing to the enhanced interfacial effect of E-bio-HJ and the good biocompatibility and cell adhesion of the methacryloylated gelatin (Gel) hydrogel, the E-bio-HJ gelatin hydrogel (E-bio-HJ/Gel) further reduced inflammation by inducing macrophage transformation to the M2 phenotype, accompanied by excellent antimicrobial properties and enhanced cell migration, angiogenesis, and collagen deposition, which synergistically promoted diabetic wound healing. This highly effective and comprehensive strategy offers a new approach for the rapid healing of diabetic wounds.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）