SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Lianjun Song,Xueyu Wang,Dongqi Wang,Qian Xiao,Haowei Xu,Qiuju Li,Lanlan He,Songdong Ding
The synthesis, Eu 3+ complexation, and selective solvent extraction of Am 3+ over Eu 3+ in nitric acid solution by 2-carboxamido-6-(1 H -pyrazol-3-yl)-pyridines (A-PzPy) ligands were described. Without the aid of any lipophilic anion source, A-PzPy ligands in methyl isobutyl ketone (MIBK) diluent demonstrated a more favorable affinity of Am 3+ than Eu 3+ at high acidity levels. Slope analysis showed the formation of 1:2 metal/ligand extracted species. The extraction was a spontaneous exothermic process. The analyses of fluorescence titration, Fourier transform infrared (FT-IR), Raman, time-resolved laser fluorescence spectrum (TRLFS), electrospray ionization mass spectrometry (ESI-MS), conductivity and microcalorimetric titration revealed that the composition of complex is [Eu(NO 3 ) 2 (H 2 O)∙2(Et- p -Tol-A-PzPy)](NO 3 ). Combining the results of solvent extraction and complexation study, the extraction mechanism was proposed. Furthermore, the stability constants (log β ) and thermodynamic parameters (Δ H , Δ S , Δ G ) for complexation of Eu 3+ with Et- p -Tol-A-PzPy were also presented.
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2015
·
IF 2.999
Yang Xia,Si Shi,Chongge Li,Chu Liang,Yongping Gan,Hui Huang,Xinyong Tao,Wenkui Zhang
A series of Sn-doped Li 3 V 2− x Sn x (PO 4 ) 3 /C ( x = 0, 0.1, 0.15, 0.2) samples were synthesized via a citric acid assisted sol–gel method. XRD patterns indicated that all the Li 3 V 2− x Sn x (PO 4 ) 3 /C samples were pure single phase with a monoclinic structure (space group P 2 1 / n ) and well crystallized. The structural refinement results and HRTEM analysis both indicated that Sn-doping did not alter the lattice structure of Li 3 V 2 (PO 4 ) 3 , but increased the unit cell volume. SEM images revealed that Sn-doping has no obvious effects on the morphology and particle size of Li 3 V 2 (PO 4 ) 3 . HRTEM, XRF and Raman results demonstrated that a thin carbon layer was coated on the surface of Li 3 V 2− x Sn x (PO 4 ) 3 /C samples with a similar carbon content and good quality. The electrochemical performance was evaluated using coin-type half cells. Among the samples synthesized in this work, Li 3 V 1.85 Sn 0.15 (PO 4 ) 3 /C exhibited the electrochemical performance in terms of specific capacity, rate capability, cycling performance. CV and EIS results implied that optimizing Sn-doping contents with x = 0.15 could greatly enhance the structural stability of Li 3 V 2 (PO 4 ) 3 during the charge–discharge processes, as well as increase electrical conductivity with a lower charge transfer resistance and a higher Li + diffusion coefficient .
✓ 已验证
DOI
高影响因子
Science of Advanced Materials
·
2016
·Vol. 8
·期 8
·1617-1627
·
IF 1.812
Wen Zhen,Su Jun-Qing,Chen Qing,Chen Li-Di
To improve the physicochemical and pharmacokinetic properties, solid lipid nanoparticles (SLNs) modified with (Polyethylene glycol-2000)-1,2-distearoyl-sn-glycero-3-phosphoethanolamine (PEG2000-DSPE) were prepared using glyceryl monostearate as a lipid carrier and resveratrol as a model
drug. Compared to ordinary SLNs, SLNs doped with low amount of PEG2000-DSPE [m(PEG2000-DSPE):m(lipids) = 1:5, w/w] exhibited improved physicochemical and pharmacokinetic properties, including higher entrapment efficiency (above 80%), smaller particle size (approximately 100 nm), more
distinguished drug release at low pH values (pH < 6.0), and longer drug circulation in vivo. According to the characterizations performed, the DSPE moiety was doped into lipid matrix to form a PEG2000-DSPE/lipid eutectic dopant, inhibiting lipid polymorphism transformation
from α-form to β-form, thereby preventing drug expulsion from the lipid. The dopant contained lattice defects, allowing for the incorporation of more resveratrol. Resveratrol was released in a sustained and pH-sensitive pattern due to nanoparticles destabilization
induced by partial protonation of PEG2000-DSPE. PEG chains distributed on the nanoparticle surface caused steric hindrance and “stealth” properties, thus maintaining dispersion stability and extending circulation time of nanoparticles. These results confirm that PEG2000-DSPE modification
effects are attributable to the matrix and surface structures of nanoparticles, which consist of a core containing DSPEinduced lattice defects and a shell coated with PEG chains.
✓ 已验证
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2021
·
IF 9.381
Zhixiang Cai,Hongbin Zhang
The chain conformational change in curdlan during carboxymethylation was investigated using nuclear magnetic resonance (NMR), circular dichroism (CD) spectroscopy, and atomic force microscopy (AFM). The distributions of carboxymethyl substituents within anhydroglucose unit (AGU) of CMCD were found to follow the order of OH (6) > OH (4) > OH (2) for CMCD with a low DS and OH (6) > OH (2) > OH (4) for CMCD with relatively high DS. The increased carboxymethylation level induced the chain conformation transition of curdlan from triple helix to random coil in water. The DS of 0.25 was the critical value of chain conformation transition, below which CMCD chains were triple helices. For DS larger than 0.25, CMCD existed in the state of random coils. The intermolecular hydrogen bonding between C2 hydroxyls in AGU sustained the triple helical conformation and stiffness of the polymer chain, which weakened with the increase in DS.
✓ 已验证
DOI
PubMed
高影响因子
Frontiers in Plant Science
·
2022
·
IF 6.627
Lei Wenli,Song Yuyang,Long Ai,Que Yanyan,He Shuzhong,Zhong Hang,Chen Yang
The medicinal plants were wildly library of natural products in drug discovery. The most active molecules with seven-membered rings skeleton represent a challenge for construction. A stereoselectivity (4 + 3) cycloadditions between allenyl ethers and substituted furans induced by chiral auxiliaries has been investigated. And the results showed significant stereoselectivities and regioselectivities. The optical cycloadducts with an oxygen-substituted seven-membered ring framework were generated by removing chiral auxiliaries under acidic conditions. The antiproliferative activity of the novel compounds displayed moderate antiproliferative effects toward T47D cells.
✓ 已验证
DOI
PubMed
高影响因子
Foods
·
2022
·Vol. 11
·期 20
·3225
·
IF 5.561
Xinrui Tang,Yingfeng An,Muhammad Waheed Iqbal,Hongri Cong,Guoyan Zhang,Yufei Zhang,Yuvaraj Ravikumar,Hossain M. Zabed,Mei Zhao,Haixing Zhou,Xianghui Qi
D-allulose is a natural rare sugar with important physiological properties that is used in food, health care items, and even the pharmaceutical industry. In the current study, a novel D-allulose 3-epimerase gene (Bp-DAE) from the probiotic strainBlautia producawas discovered for the production and characterization of an enzyme known as Bp-DAE that can epimerize D-fructose into D-allulose. Bp-DAE was strictly dependent on metals (Mn2+and Co2+), and the addition of 1 mM of Mn2+could enhance the half-life of Bp-DAE at 55 °C from 60 to 180 min. It exhibited optimal activity in a pH of 8 and 55 °C, and theKmvalues of Bp-DAE for the different substrates D-fructose and D-allulose were 235.7 and 150.7 mM, respectively. Bp-DAE was used for the transformation from 500 g/L D-fructose to 150 g/L D-allulose and exhibited a 30% of conversion yield during biotransformation. Furthermore, it was possible to employ the food-grade microbial speciesBacillus subtilisfor the production of D-allulose using a technique of whole-cell catalysis to circumvent the laborious process of enzyme purification and to obtain a more stable biocatalyst. This method also yields a 30% conversion yield.Keywords:D-allulose 3-epimerase;D-allulose;Blautia produca;probiotics;biochemical characterization;biotransformation
✓ 已验证
DOI
PubMed
高影响因子
SOLID STATE IONICS
·
2020
·
IF 3.107
Erqing Zhao,Yudi Guo,Yuan Xin,Guangri Xu
Nasicon-type Li 1+x Al x Ge 2-x (PO 4 ) 3 (x = 0–0.5) electrolytes have been prepared via a facile and economic method. All synthetic electrolyte samples show Nasicon structure and good crystallinity . The Al doping content has a great influence on the electrical conductivity of electrolyte. The electrolyte with the composition of Li 1.4 Al 0.4 Ge 1.6 (PO 4 ) 3 exhibits a highest electrical conductivity of 2.72 × 10 −4 S/cm at room temperature , which is mainly attributable to fewer impurity and dense electrolyte structure. The LiFePO 4 /Li cell assembled with this electrolyte delivers an initial specific discharge capacity of 127.86 mAh g −1 at a charge/discharge current density of 0.5C at 60 °C, which shows an excellent cycling performance with high discharge capacity of 131.2 mAhg −1 after 150 cycles. These results suggest that the Li 1.4 Al 0.4 Ge 1.6 (PO 4 ) 3 electrolyte is a potential electrolyte for all solid state lithium-ion battery.
✓ 已验证
DOI
高影响因子
SURFACE & COATINGS TECHNOLOGY
·
2021
·
IF 4.158
Bin Li,Boxuan Jin,Ruochen Zhang,Kaixuan Ma,Xianwen Wu,Lei Dai,Ling Wang,Zhangxing He
Metal zinc is used as anode in aqueous zinc-ion batteries due to its environmental protection, abundant storage, and high theoretical capacity. However, zinc anode has many challenges such as side reactions and zinc dendrites, which impede the further development of aqueous zinc-ion batteries. A facile strategy of constructing Sn doped NaTi 2 (PO 4 ) 3 (NTP/Sn) protective layer on surface of zinc anode (Zn@NTP/Sn) was adopted to enhance the cycling stability of zinc anode in this work. Sn doped NaTi 2 (PO 4 ) 3 was used to realize high-performance zinc anode via the structure design and interfacial characteristics, which are beneficial to accelerating transfer of Zn 2+ and improving interface performance. The average voltage hysteresis of Zn@NTP/Sn symmetric cell is only 17.4 mV at the current density of 0.4 mA cm −2 , which is much lower than that of bare Zn (75.8 mV) and Zn@NTP (43.7 mV) symmetric cells. Furthermore, Zn-MnO 2 full cell using Zn@NTP/Sn anode also shows good cycling performance. After 500 cycles at a current density of 1.2 A g −1 , Zn@NTP/Sn-MnO 2 full cell has the highest capacity of 124.2 mAh g −1 . While the bare Zn-MnO 2 and Zn@NTP-MnO 2 full cells only have 39.3 mAh g −1 and 74.2 mAh g −1 . The excellent electrochemical performance is related to improvement of wettability , increase of cell volume, and reduction of side reactions. In general, this work realizes a synergistic strategy combining structural design and interfacial modification by doping Sn for NTP as a protective coating layer for zinc anode, which provides a simple strategy for high-performance rechargeable aqueous zinc-ion batteries.
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Yu Zhou,Zishuai Zhang,Yu Zhao,Jiefei Liu,Kwok-ho Lam,Xingyu Zheng,Hongtao Lou,Xianhua Hou
Aqueous rechargeable batteries have promising application in large-scale energy storage owing to their cost-effective, eco-friendly, high safety and good electrochemical performance. An aqueous rechargeable hybrid sodium/zinc battery with Zn anode, Na 3 MnTi(PO 4 ) 3 cathode and 0.5 mol L -1 CH 3 COONa and Zn(CH 3 COO) 2 mixed electrolyte has been designed for the first time. The battery delivered a reversible and stable capacity of 95.0 mAh g −1 at 1.5 C for 50 cycles with a high and flat working voltage of 1.75 V vs. Zn 2+ /Zn. Impressively, the battery showed the excellent cycling performance and superior rate capability, which can be cycled at 10.0 C for 2000 cycles with a capacity retention of 93.6% and a reversible capacity of 55.6 mAh g −1 at 30.0 C. Meanwhile, the co-intercalation mechanism of hybrid Na + and Zn 2+ in the cathode is elucidated by cyclic voltammogram, ex-situ XRD, ex-situ XPS and Rietveld refinement analysis. This work gets insight into the charge/discharge processes of hybrid ions for NASICON-structured Na 3 MnTi(PO 4 ) 3 , providing a feasible way to design cost-effective, high safety and long-term aqueous rechargeable batteries.
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CHEMISTRY
·
2021
·Vol. 39
·期 10
·2889-2897
·
IF 6
Cuiyuan Liang,Xin Wang,Dexin Yu,Wei Guo,Feng Zhang,Fengyu Qu
Main observation and conclusion Detection of hydrazine originated from electrochemical media has recently gained considerable attention in the sensing field. Herein, to improve electron transfer capacity, a polyoxometalate metal-organic framework (POMOF, NENU-3) is in-situ nucleated onto the carboxyl functionalized reduced graphene oxide (CFG) (NENU-3/CFG, abbreviation N3/CFG). The N3/CFG supported onto carbon cloth electrodes (CCEs) has been investigated for hydrazine detection. The amperometric results display that the POMOF/CFG to hydrazine has a broad linear range (0.09—362.5 μmol/L) and low detection limit (24 nmol/L). In addition, the POMOF/CFG-based sensors possess good anti-interference capability, boosted stability and feasibility. Furthermore, when applied to the detection of practical samples, acceptable relative recoveries of 96.26%—107.30% are obtained.
✓ 已验证
DOI
高影响因子
MOLECULES
·
2018
·Vol. 23
·期 12
·3369
·
IF 3.098
Li-Min Zhao,Zhen Guo,Yi-Jie Xue,Jun Zhe Min,Wen-Jing Zhu,Xiang-Yu Li,Hu-Ri Piao,Cheng Hua Jin
The transforming growth factor-β (TGF-β), in which overexpression has been associated with various diseases, has become an attractive molecular target for the treatment of cancers. Thirty-two quinoxaline-derivatives of 3-substituted-4-(quinoxalin-6-yl) pyrazoles14a–d,15a–d,16a–d,17a–d,18a–d,19a–d,25a,25b,25d,26a,26b,26d,27b, and27dwere synthesized and evaluated for their activin TGF-β type I receptor kinase and p38α mitogen activated protein (MAP) kinase inhibitory activity in enzymatic assays. Among these compounds, the most active compound19binhibited TGF-β type I receptor kinase phosphorylation with an IC50value of 0.28 µM, with 98% inhibition at 10 µM. Compound19balso had good selectivity index of >35 against p38α MAP kinase, with 9.0-fold more selective than clinical candidate, compound3(LY-2157299). A molecular docking study was performed to identify the mechanism of action of the synthesized compounds and their good binding interactions were observed. ADMET prediction of good active compounds showed that these ones possess good pharmacokinetics and drug-likeness behavior.Keywords:TGF-β;ALK5 inhibitor;kinase assay;selectivity;docking
✓ 已验证
DOI
PubMed
高影响因子
RESEARCH ON CHEMICAL INTERMEDIATES
·
2012
·Vol. 38
·期 7
·1699-1705
·
IF 0.697
Xie Wen Lin,Xiao Chuang Ping,Xie Ling,Zhou Ying,Li Xue Feng,Tang Xu Fu,Yuan Chun Tao,Qiu Ming Hua
4 - Substituted 3-hydroxy-2(1 H )-pyridinones 2 were prepared by Mannich reaction of 3-hydroxy-2(1 H )-pyridinones with secondary amines and formaldehyde. The isolated products were then reacted with aromatic amines in the presence of NaIO 3 as oxidant via oxidation–Michael addition to yield 4,5,6-trisubstituted-2,3-pyridinediones 3 in good yields (80.2–88.9%). The structures of the products were characterized by 1 H NMR, ESI-MS, and IR, and elemental analysis.
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）