Chinese Journal of Natural Medicines
·
2014
·
IF 0
De-Biao YAN,Dong-Ping ZHANG,Ming LI,Wen-Yuan LIU,Feng FENG,Bin DI,Qing-Long GUO,Ning XIE
To synthesize a series of 3-, 4-, and/or 11-trihydroxy modified bergenin derivatives and evaluated their cytotoxic activity in vitro . The phenolic hydroxyl groups of bergenin were protected by benzyl groups with benzyl bromide. Treatment of dibenzyl bergenin with the corresponding acid in the presence of EDC·HCl and DMAP in CH 2 Cl 2 , followed by hydrogenation over Pd/C catalysts, afforded derivatives of bergenin esters. All of the target compounds were identified by IR, MS, and 1 H NMR. Twenty-six novel and three known derivatives of bergenin esters were synthesized. Their cytotoxicity values were evaluated by the MTT assay on the inhibition of DU-145 and BGC-823 cells in vitro . Several triply-substituted ( 3a, 4a, 5a, 6a, 7a ) and doubly-substituted ( 8b, 9b ) bergenin derivatives exhibited higher cytotoxic activity than bergenin. The result showed that the size of substituents and the lipophilicity of the bergenin esters displayed an important role on their cytotoxic activity.
研究领域:
药物化学
·
肿瘤学
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DOI
PubMed
CHEMICAL RESEARCH IN CHINESE UNIVERSITIES
·
2015
·Vol. 31
·期 6
·1051-1055
·
IF 0.875
Fang Xiaoting,Guo Hongyu,Yang Fafu,Bai Xiaoyan
By the Schiff-base condensation of formacyl calix[4]crown( 2 ) with raw chitosan, a novel calix[4]crown-grafted chitosan chelating polymer( 3 ) was conveniently prepared in good yield. The structure of polymer 3 was confirmed by elemental analysis, infrared(IR) spectrometry and X-ray diffraction(XRD) analysis. The elemental analysis suggests that the grafting degree of calixcrown unit was 22% on the amino groups of chitosan. The morphological characteristic of polymer 3 was studied by scanning electron microscopy(SEM). Polymer 3 possessed loose porous and smooth morphology of surface. The dyes adsorption abilities of polymer 3 for a series of organic dyes[Orange I(OI), Neutral red(NR), Victoria blue B(VB) and Brilliant green(BG)] were studied by solid-liquid adsorption experiments. The adsorption percentages increased from 45%―60%(raw chitosan for dyes) to 75%―90%(polymer 3 for dyes). The highest adsorption percentage reached 89% for VB. The saturated adsorption capacities for OI, NR, VB and BG were as high as 622, 564, 854 and 781 mg/g, respectively. The adsorption abilities kept stable at 70%―90% in the scope of pH=5―9. The adsorption abilities for anionic dye(OI) decreased gradually with the increase of pH and the opposite trend was observed for cationic dyes(NR, BG, VB). The adsorption percentages were 70%―90% after five times’ cycles for adsorption.
研究领域:
材料科学
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环境科学
·
化学工程
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DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2016
·Vol. 134
·期 8
·
IF 1.866
Defa Hou,Hanbing Ma,Xiuyun Li,Jie He,Huiwei Liao
A novel easily curing system of 2,2- bis (4-cyanatophenyl) propane(BACY) was prepared by employing 4,4′-(Hexafluoroisopropylidene) Diphenol (BPAF) as modifier. The curing efficiency of BPAF was evaluated by means of differential scanning calorimetry (DSC) and Fourier translation infrared spectroscopy analysis (FTIR). It was found that the exothermic peak temperature ( T p ) was 168 °C when the content of BPAF/BACY was 15/85 by weight, while the temperature of BACY was 215 °C under the same conditions when trace of cobalt(III) acetylacetonate(CoAt(III)) was added. Besides, BPAF/BACY system owned outstanding properties including excellent curing characteristics, high shear strength, remarkable dielectric properties and high thermal stability in contrast to BACY, 4,4′-(1-methylethylidene) bisphenol(BPA)/BACY, and nonylphenol(NoP)/BACY systems. Moreover, the properties of cured BPAF/BACY modified by different proportions of BPAF were studied in detail. It was shown that moderate BPAF was conducive to most properties of polycyanurate, and the optimal proportion of BPAF/BACY was 15/85 by weight. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44518.
研究领域:
材料科学
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高分子化学
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DOI
高影响因子
Separations
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2021
·Vol. 8
·期 6
·72
·
IF 2.777
Xiqiang Liu,Hui Zhang,Yunlong Liu
Apatite is an important carrier of rare earth elements (REEs) and phosphorite is a potential REEs resource. However, the influence of hydrothermal fluids on the migration and enrichment of REE in apatite remains controversial. The experimental study of the interaction between REE-bearing fluid and apatite is one of the essential ways to understand the chemical behavior of rare earth elements in apatite. In this study, we conducted the fluid–mineral reaction experimental study (at 400 °C, 50 MPa and 4–16 wt %) between high lanthanum (La) content hydrothermal solution and low REE content to reveal the influence of different salinities on the diffusion of rare earth elements in fluorapatite. Based on in situ geochemical analyses of experimental products, we show that the diffusion coefficients of La in fluorapatite are between 3.24 × 10−15and 5.88 × 10−15m2/s. The salinity of the fluid has a great influence on the diffusion coefficient, with the increase of salinity, the diffusion coefficient increase.Keywords:water–mineral reaction;fluorapatite;lanthanum;diffusion
研究领域:
地质学
·
地球化学
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DOI
高影响因子
FOOD MICROBIOLOGY
·
2026
·
IF 5.4
Liangliang Gao,Tengjie Li,Zengrong Xiong,Mingnan You,Jun Zhang,Nengguo Tao
In this study, N'-(4-fluorophenyl)-2-pyridinecarbohydrazide (2-FPH), N'-(4-fluorophenyl)-3-pyridinecarbohydrazide (3-FPH), and N'-(4-fluorophenyl)-4-pyridinecarbohydrazide (4-FPH), which showed considerable antifungal activities against the prochloraz-resistant Penicillium italicum strain (PiR2), were designed and synthesized. Among these, 2-FPH displayed the strongest antifungal activity against PiR2 growth, with minimum inhibitory concentrations (MIC) of 12.5 μg/mL and minimum fungicidal concentrations (MFC) of 25 μg/mL. In vivo antifungal and hemolytic toxicity tests showed that 2-FPH effectively prevented PiR2 infection of citrus fruits, but exhibited exceptionally low hemolytic toxicity. At equivalent concentrations, its biological safety and control efficacy were far superior to those of prochloraz. According to morphological findings, 2-FPH increased cell membrane permeability, caused cell swelling and morphological abnormalities, disrupted structural integrity, and decreased chitin content in cell walls. Physiological, biochemical, and molecular biology investigations indicated that 2-FPH binds to succinate dehydrogenase (SDH), inhibits its enzymatic activity, and suppresses associated gene expression. This decreases intracellular ATP levels, disrupts normal mitochondrial function, and triggers a substantial increase in reactive oxygen species (ROS). In summary, 2-FPH shows promising potential as a possible fungicide and succinate dehydrogenase inhibitor for managing citrus blue mold.
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产品关联
DOI
PubMed
高影响因子
ChemPlusChem
·
2024
·
IF 3
Yong Wang,Xueying Lin,Xianyu Ying,Shan Hu,Hongjun Zhu
A facile C–H amination of quinazoline employing N-fluorobenzenesulfonimide (NFSI) as the amination source has been disclosed in the absence of any metal, oxidant or additive. The methodology shows a board range of quinazolines with different functional groups in moderate to good yields up to 87%. Furthermore, gram-scale reaction, desulfonylation to amine and synthesis of pharmaceutical intermediate were also investigated, which demonstrates potential applications in medicinal chemistry. A plausible amination mechanism is proposed via F+ transfer accompanied by the removal of one molecule of PhSO2F. DFT studies with experimental work suggest that the mechanism via F+ transfer is more favorable than the free radical one.
研究领域:
有机化学
·
药物化学
·
合成化学
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DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2022
·
IF 6.633
Lianjing Mao,Pengrui Zhang,Huiqun Ju,Xiaolong Zhou,Zixuan Xue,Ciming Wang,Jinhe Sun,Yongzhong Jia,Fei Shao,Xingwu Zou,Bo Li,Yan Jing
The evolution of the nuclear industry is inextricably linked to lithium isotopes. With its distinct benefits, the solvent extraction approach is projected to achieve industrial separation of lithium isotopes. However, the lack of studies on the extraction process conditions and mechanisms has limited the development of multi-stage processes. In this paper, based on the 4-NO 2 -B15C5/[BMIm][NTf 2 ] system, the process conditions and extraction mechanism of the system were investigated by thermodynamic and kinetic studies. The results indicate that lithium isotope separation is a spontaneous exothermic process controlled by diffusion. In addition, DFT calculations show that the binding sites of crown ether and Li + are located in the coronary heart of crown ether, and electrostatic and van der Waals forces mainly exist between them. On this basis, a 10-stage cross-flow extraction experiment was carried out using crown ether as the extractant. The aqueous phase feed solution is fully utilized, and the 7 Li abundance is increased to 93.29 %. In summary, this research provides a foundation for the development of synergistic multi-stage extraction techniques in the future.
研究领域:
化学工程
·
核工业技术
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DOI
高影响因子
Sustainable Energy & Fuels
·
2021
·Vol. 5
·期 8
·2347-2353
·
IF 6.367
Longhui Deng,Zhihao Zhang,Yifeng Gao,Qiu Xiong,Zicheng Li,Jianbin Xu,Zilong Zhang,Jun Chen,Peng Gao
Perovskite solar cells (PSCs) have achieved tremendous success in advancing high power conversion efficiencies. However, defect-induced recombination at grain boundaries (GBs) and the surface of polycrystalline perovskites seriously hinder the further performance enhancement and environmental stability of PSCs. Here, a simple passivating molecule, 4-nitrophthalonitrile (4NPN) with σ–π accepting nitro (–NO2) and cyano groups (–CN), was employed to passivate the charged defects in perovskites. The addition of electron-deficient 4NPN into the perovskite layer of PSCs could not only enhance VOC and the FF, leading to high PCE over 22% but also improved environmental stability. These improvements were attributed to the effective passivation of the defects in the perovskite film by the strongly polarized nitro/cyano groups. In addition, the electron-deficient 4NPN could slightly adjust the energy level of the perovskite facilitating more efficient hole transfer. This work demonstrates the role of strong electron-withdrawing nitro/cyano groups in passivating the vacancy-defects of perovskites and 4NPN as a simple passivator conducive to obtaining high-performance PSCs.
研究领域:
材料科学
·
能源科学
✓ 已验证
DOI
高影响因子
CARBON
·
2017
·
IF 6.337
Dandan Su,Yuanyuan Zhang,Zhijie Wang,Qijin Wan,Nianjun Yang
To decorate graphene nano platelets (GNPs) with uniform, non-aggregated, and well-distributed gold nanoparticles (Au NPs) as well as to improve the stability of GNPs on the electrode surface, a one step in situ co-electrodeposition procedure has been developed using a mixture of sol-gel, β-cyclodextrin (β-CD), and the gold precursor of HAuCl 4 . The in situ co-electrodeposited Au NPs have been characterized using scanning electron microscope and transmission electron microscope. Based on the composite of sol-gel, β-CD, Au NPs, and GNPs, a modified electrode has been constructed. After its characterization using voltammetry and impedance, voltammetry of 4-nonylphenol has been investigated on such an electrode, revealing an irreversible, adsorption-controlled, one-electron-and-one-proton involved oxidation process . The oxidation peak current is much enhanced. This enhancement is interpreted as a synergistic effect among GNPs, Au NPs, sol-gel, and β-CD. Using this electrode, a wide linear range (0.01–1.0 μM) and a low detection limit (down to 3.0 nM) for the monitoring of 4-nonylphenol have been achieved. Such a stable electrode is therefore promising for the reproducible and sensitive monitoring of 4-nonylphenol in the environment.
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DOI
高影响因子
Solar RRL
·
2019
·Vol. 4
·期 1
·1900410
·
IF 0
Qiong Yan,Shuying Cheng,Xue Yu,Hongjie Jia,Junjie Fu,Caixia Zhang,Qiao Zheng,Sixin Wu
Partial cation substitution is an effective way to inhibit defects and carrier recombination, which can improve the efficiency of Cu 2 ZnSn(S,Se) 4 (CZTSSe) solar cells. Herein, flexible Cu 2 Zn 1− x Cd x Sn(S,Se) 4 ( x = 0–15%) solar cells are fabricated on Mo foils with partial Cd substitution for Zn via a green solution-process. The best device performance can be achieved when Cd/(Zn + Cd) = 8%, with an efficiency up to 6.49% and a significantly improved device repeatability. The E U decreases from 24 to 15 meV, indicating that antisite defects and band tailings are effectively suppressed. C – V data reveal that W d and V bi are enhanced after doping Cd, resulting in a stronger built-in electric field which facilitates Fermi-level splitting and hence increases band bending of the absorber toward the junction interface. Furthermore, the mechanism of current shunting is studied using an equivalent circuit model with three parallel current pathways to fit J – V curves. The key parameters for the solar cell diode such as A , J 0 , and R sh are significantly improved by partially substituting Zn with Cd, demonstrating that current shunting loss is suppressed and the junction quality is improved, resulting in a significant improvement in device repeatability.
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DOI
RSC Advances
·
2018
·Vol. 8
·期 49
·27686-27694
·
IF 2.936
Xue Yu,Shuying Cheng,Qiong Yan,Jinling Yu,Wen Qiu,Zhengji Zhou,Qiao Zheng,Sixin Wu
Cation substitution plays a crucial role in improving the efficiency of Cu2ZnSn(S,Se)4 (CZTSSe) solar cells. In this work, we report a significant efficiency enhancement of flexible CZTSSe solar cells on Mo foils by partial substitution of Cu+ with Ag+. It is found that the band gap (Eg) of (Cu1−xAgx)2ZnSn(S,Se)4 (CAZTSSe) thin films can be adjusted by doping with Ag with x from 0 to 6%, and the minimum Eg is achieved with x = 5%. We also found that Ag doping can obviously increase the average grain size of the CAZTSSe absorber from 0.4 to 1.1 μm. Additionally, the depletion width (Wd) at the heterojunction interface of CAZTSSe/CdS is found to be improved. As a result, the open-circuit voltage deficit (Voc,def) is gradually decreased, and the band tailing is suppressed. Benefiting from the enhanced open-circuit voltage (Voc), the power conversion efficiency (PCE) is successfully enhanced from 4.34% (x = 0) to 6.24% (x = 4%), and the Voc,def decreases from 915 to 848 mV.
研究领域:
光伏技术
·
材料科学
·
薄膜太阳能电池
·
半导体材料
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2014
·
IF 2.045
Jun-su Jin,Xing Fan,Haifei Zhang,Yi-wei Wang,Ze-ting Zhang
The equilibrium solubilities of 4-aminosalicylic acid (PAS) in supercritical carbon dioxide (SCCO2) and subcritical 1,1,1,2-tetrafluoroethane (R134a) are crucial to the process of supercritical and subcritical extraction. After reliability tests of the experimental apparatus were carried out and confirmed, measurements of the solubilities of PAS in SCCO2 and subcritical R134a were implemented from (11.0 to 21.0) MPa at temperatures of (308 to 328) K by the dynamic method in SCCO2 and from (5.0 to 15.0) MPa at temperatures of (308 to 328) K by the static method in subcritical R134a, respectively. It was found that the solubility of PAS is much higher in subcritical R134a than in SCCO2 under the same operational conditions (temperature and pressure). The solubility enhancement factor (δ) was calculated and analyzed. Four density-based models (Chrastil, K-J, M-S-T, and S-S) were used to correlate the PAS solubility data in SCCO2 and subcritical R134a. The calculated results showed that the reasonable agreement was obtained with the experimental solubility data.
研究领域:
化学工程
·
热力学
·
超临界流体技术
·
药剂学
·
分离过程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）