ORGANIC PROCESS RESEARCH & DEVELOPMENT
·
2023
·
IF 3.4
Junjie Li,Wei Feng,Shichun Weng,Zichao Guo,Wanghua Chen
3,4-bis(4-Aminofurazano-3-yl) furoxan (DATF) is a key precursor for the high-energy explosive 3,4-bis(4-nitrofurazano-3-yl) furoxan (DNTF), and it is also a high-nitrogen content energetic material. In this paper, the synthesis process of DATF was characterized using the HPLC technique, and the effects of four reaction parameters have been thoroughly studied. The thermal risk analysis for DATF synthesis was conducted with a reaction calorimeter (RC1) and an accelerating rate calorimeter. It was found that extracting the intermediate 3-amino-4-oxycyanofurazan from the aqueous to organic phases was an important way to improve the yield of DATF. Therefore, hydrophobic ethyl acetate was selected as one reaction solvent. The higher yield of DTAF obtained was about 60%. In addition, HPLC monitoring and reaction calorimetry results indicated that the rate of diazotization and decomposition of diazonium salt was feeding-controlled, and the cycloaddition reaction was a slow process. Most of the reaction heat has been released by the diazotization and decomposition of diazonium salt, while the heat effect of cycloaddition was not significant. Thermal stability analysis supported the conclusion that the decomposition of the reaction mixture was hardly possible to be triggered by the reaction heat. The thermal risk of DATF synthesis was low.
研究领域:
化学工程
·
安全科学
·
材料科学
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产品关联
DOI
高影响因子
MOLECULES
·
2016
·Vol. 21
·期 3
·299
·
IF 2.465
Bo Jin,Rongzong Zheng,Rufang Peng,Shijin Chu
Five new bis(3-hydroxy-4-pyridinone) tetradentate chelators were synthesized in this study. The structures of these tetradentate chelators were characterized by1H-NMR,13C-NMR, FT-IR, UV-vis, and mass spectral analyses. The binding abilities of these tetradentate chelators for uranyl ion at pH 7.4 were also determined by UV spectrophotometry in aqueous media. Results showed that the efficiencies of these chelating agents are dependent on the linker length. Ligand4bis the best chelator and suitable for further studies.Keywords:chelating agent;3-hydroxy-4-pyridinone;uranium;tetradentate chelator
研究领域:
化学
·
环境科学
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DOI
PubMed
高影响因子
ULTRASONICS SONOCHEMISTRY
·
2014
·
IF 3.816
Wang Liju,Keyume Ablajan,Feng Jun
A rapid and efficient ultrasound-promoted one-pot synthesis of spiro[indoline-3,4′-pyrano[2,3-c]pyrazole] derivatives is described here. The reaction of substituted phenylhydrazine and dialkyl acetylenedicarboxylate with substituted isatin and malononitrile is catalyzed by l -proline to give good-to-excellent yields in water/ethanol (v/v, 1:1) at room temperature.
研究领域:
有机化学
·
催化反应
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DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Xiuna Tian,Youfeng Wen,Hongjian Dou,Lingyuan Wu,Changjun Wang,Youzi Zhang
In the clinical diagnosis and treatment of diseases, there is an urgent need to find suitable materials for real-time temperature monitoring of biological tissues. The paper provides a detailed study of the effects of Nd 3+ doping concentration on the negative thermal expansion performance and NIR fluorescence properties of Sc 2 (MoO 4 ) 3 . The results obtained from Rietveld refinement of in-situ XRD data indicates that high concentration of Nd 3+ doping significantly influences the negative thermal expansion performance of the material, as well as alters the temperature-dependent changes in NIR fluorescence intensity and lifetime. In addition, a NIR fluorescence lifetime temperature probe doped with Nd 3+ /Yb 3+ /Er 3+ has been constructed. When the temperature increased from 303 K to 403 K, the fluorescence intensity of the probe at 1538 nm increased by a factor of 127.5. Furthermore, as the temperature rose from 323 K to 403 K, the fluorescence lifetime of the probe at 1538 nm extended from 41.93 μs to 204 μs. By utilizing the lifetime of Er 3+ for temperature sensing, a relative sensitivity of 6.03%K −1 was achieved at 323 K, indicating significant potential application value of this probe in the field of biological temperature measurement.
研究领域:
材料科学
·
生物医学工程
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产品关联
DOI
高影响因子
JOURNAL OF DAIRY SCIENCE
·
2022
·
IF 4.225
Shen Duan,Xin-Yao Wang,Xu Feng,Yue Ma,Zhong Zheng,Chao-Mei Ma
ABSTRACT Cynomorium songaricum is a traditional medicine and also a food material that is eaten raw or processed as tea or beverages. As a featured plant in semi-desert grasslands, C. songaricum is also eaten by the cattle and sheep in the area. This research study fed dairy sheep C. songaricum to determine the flavan-3-ols in sheep milk. Catechin (Cat), epicatechin (Epi), procyanidin A1 (A1), procyanidin A2 (A2), and procyanidin B1 (B1) were detected in sheep milk with the concentration being Epi > A2 > Cat > B1 > A1 at 24 h after the administration of C. songaricum . Neither A1 nor A2 were detected in the methanol extract of C. songaricum . Cysteine degradation of the plant revealed that in addition to Epi, A2 was the extending unit of the polymeric flavan-3-ols in C. songaricum , indicating that A2 is released digestively from the polymers and enters the milk. Procyanidin B-1 was converted to A1 on incubation in raw but not heated milk, indicating that the A1 in milk is the enzymatically transformed product of B1. Accelerated oxidation showed that the flavan-3-ols, B1, Cat, and Epi significantly protects the unsaturated triacyglycerols in the milk from oxidation. The flavan-3-ol could slow down the oxidation of glutathione and the latter may play an important role in preventing the milk triglycerides from oxidation. Flavan-3-ols are polyphenols with many health benefits. The present research revealed the antioxidant activities of flavan-3-ols that could be absorbed to sheep milk, adding new evidences for the values of these flavan-3-ols and for the milk.
研究领域:
食品科学
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动物营养学
·
植物化学
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DOI
高影响因子
RSC Advances
·
2022
·Vol. 12
·期 38
·25068-25080
·
IF 4.036
Fen-Fen Yang,Ming-Shan Shuai,Xiang Guan,Mao Zhang,Qing-Qing Zhang,Xiao-Zhong Fu,Zong-Qin Li,Da-Peng Wang,Meng Zhou,Yuan-Yong Yang,Ting Liu,Bin He,Yong-Long Zhao
Multi-drug-resistant microbial pathogens are a serious global health problem. New compounds with antibacterial activity serve as good candidates for developing novel antibacterial drugs which is very urgent and important. In this work, based on the unique scaffold of indirubin, an active ingredient of traditional Chinese medicine formulation Danggui Luhui Wan, we synthesized 29 indirubin-3′-monoximes and preliminarily evaluated their antibacterial activities. The antibacterial activity results demonstrated that the synthesized indirubin-3′-monoximes 5a–5z and 5aa–5ad displayed good potency against S. aureus ATCC25923 (MIC = 0.4–25.6 μg mL−1). Among them, we found that the 5-F, 5-Cl and 7-CF3 substituted indirubin-3′-monoximes 5r, 5s and 5aa also showed better antibacterial efficiency for S. aureus (MICs up to 0.4 μg mL−1) than the prototype natural product indirubin (MIC = 32 μg mL−1). More importantly, indirubin-3′-monoxime 5aa has certain synergistic effect with levofloxacin against clinic multidrug-resistant S. aureus (fractional inhibitory concentration index: 0.375). In addition, relevant experiments including electron microscopy observations, PI staining and the leakage of extracellular potassium ions and nucleic acid (260 nm) have been performed after treating S. aureus with indirubin-3′-monoxime 5aa, and the results revealed that indirubin-3′-monoximes could increase the cell membrane permeability of S. aureus. Although indirubin-3′-monoxime 5aa showed some cytotoxicity toward SH-SY5Y cells relative to compounds 5r and 5s, the skin irritation test of male mice after shaving showed that compound 5aa at a concentration of 12.8 μg mL−1 had no toxicity to mouse skin, and it could be used as a leading compound for skin antibacterial drugs.
研究领域:
药理学
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微生物学
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药物化学
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DOI
PubMed
高影响因子
Journal of Materials Chemistry B
·
2018
·Vol. 6
·期 47
·7862-7870
·
IF 4.776
Jian Chen,Dongya Zhang,Yan Zou,Zhongjie Wang,Mingcong Hao,Meng Zheng,Xue Xue,Xiaoxi Pan,Yiqing Lu,Jiefei Wang,Bingyang Shi
Nanohybrids fabricated with upconversion nanoparticles (UCNPs) and gold nanoparticles (NPs) hold great promise for near-infrared photothermal therapy (NIR-PTT) and upconversion fluorescence imaging. However, the obstacles of poor solubility in water and finite hydrophilic modification method for UCNPs limit their application in biological fields. Herein, we report a novel UCNP@Al(OH)3/Au nanohybrid mediated by a highly hydrophilic and biocompatible Al(OH)3 layer to realize a synergistic targeted PTT and fluorescence imaging capability to U87MG tumor-bearing mice under NIR light irradiation. The modification with Al(OH)3 layers can improve the water solubility of UCNPs. And cytotoxicity assays and hemolysis assay showed that the modification with Al(OH)3 layers makes UCNPs have low cytotoxicity and good biocompatibility. In addition, the Al(OH)3 layers are thin enough to allow fluorescence resonance energy transfer (FRET) between UCNPs and gold NPs to occur, giving the NPs a good PTT effect for tumor-bearing mice. Meanwhile, as the pH-sensitive Al(OH)3 layers decompose in acidic tumor microenvironments with Au NPs detached from their surface, the FRET effect no longer occurred, subsequently leading to the fluorescence intensity of naked UCNPs being recovered for good imaging effects. The study suggests that Al(OH)3 mediation layer as a promising hydrophilic nanoplatform can potentially be used for the preparation of superior hydrophilic NPs and pH-stimulated drug release carriers for theranostic application in vivo.
研究领域:
生物医学工程
·
纳米医学
·
肿瘤学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2017
·
IF 2.323
Chenyang Wen,Xianyang Meng,Kaixin Wei,Jiangtao Wu
The compressed liquid viscosities of 2-methylpentane, 3-methylpentane, and 2,3-dimethylbutane were measured using a vibrating-wire viscometer over the temperature range of (273 to 343) K and at pressures up to 40 MPa. The combined expanded uncertainty of the reported viscosity is about 2% with a confidence level of 0.95 (k = 2). An empirical Andrade–Tait equation was used to correlate the viscosity as a function of temperature and pressure with average absolute percentage deviations of 0.19%, 0.23%, and 0.25%, respectively.
研究领域:
化学工程
·
物理化学
✓ 已验证
DOI
高影响因子
JOURNAL OF RARE EARTHS
·
2025
·
IF 7.2
Dilare Halmurat,Xinyu Zhang,Litipu Aihaiti,Rong-Jun Xie
Eu 2+ -doped phosphors show broadband absorption, tunable emission and high quantum efficiency due to the parity-allowed 5d→4f transitions, allowing them to be used in solid-state lighting. To expand their applications in other fields such as detection and sensing technologies, the Eu 2+ emission needs to be tuned into the near-infrared region, but it is a big challenge to obtain Eu 2+ near-infrared region emitters due to the absence of host compounds with extremely large crystal-field splitting. In this work, we chose M 4 Li(BN 2 ) 3 (M = Ca, Sr, Ba) as a host and realize the near-infrared region emission of Eu 2+ in it. Among these phosphors, Ba 4 Li(BN 2 ) 3 :Eu 2+ exhibits the longest emission of 880 nm and the largest full-width at half maximum of 276 nm under 450 nm excitation, while Ca 4 Li(BN 2 ) 3 :Eu 2+ and Sr 4 Li(BN 2 ) 3 :Eu 2+ emit at 740 and 680 nm, respectively. We observe an interesting phenomenon that the energy shift of emission is linearly related to the radius difference between the alkaline earth cation and the activator Eu 2+ in this system.
研究领域:
材料科学
·
光学
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产品关联
DOI
高影响因子
POLYMER
·
2019
·
IF 3.771
Fuzhou Wang,Guoyong Xu,Qingshan Li,Ryo Tanaka,Yuushou Nakayama,Takeshi Shiono
The first example of a 3-alkene polymerization has been successfully achieved with 3-heptene in the presence of phenyl-substituted α- diimine nickel precatalysts activated by dMMAO, and compared with the corresponding linear alkenes, i.e., 1-pentene, 2-hexene and 4-octene polymerizations. The microstructures of the produced poly(3-heptene), which consists of ethyl , propyl and butyl branches indicated the 3,4- and 4,3-insertion, followed by chain-walking, with incorporation of a small fraction of long methylene sequences of 1,7-enchainment via monomer-isomerization. Late-transition metal catalyzed polymerization reactions of internal alkenes to synthesize novel polyolefin materials are highly important and also highly challenging. Upon activation with dried modified methylaluminoxane (dMMAO), the first example of a 3-alkene polymerization has been successfully achieved for 3-heptene catalyzed by phenyl-substituted α- diimine nickel complexes in comparison, and compared with the polymerizations of the corresponding linear alkenes, i.e., 1-pentene, 2-hexene and 4-octene. The results indicate that the polymerization of 3-heptene was achieved via chain-walking to generate branched amorphous polymers with glass transition temperature of ca. −68 °C. The microstructures of the produced poly(3-heptene) indicated the 3,4- and 4,3-insertion followed by chain-walking, the latter being predominant. The NMR analyses of the polymers showed that the obtained poly(3-heptene) possessed ethyl, propyl and butyl branches and a small amount of the long methylene sequence of 1,7-enchainment via monomer-isomerization. The branches structures were significantly dependent on the polymerization temperature, and the content of propyl branches derived from 3,4-insertion decreased with an increase in the polymerization temperature.
研究领域:
材料科学
·
高分子化学
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产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2022
·
IF 9.231
Jia Cheng Qian,Dan Liu,Li Ping Lin,Wen Jing Zhu,Ren Xiang Tan
Kimchi is a globally consumed food with diverse health-benefits, but the low-abundance bioactive compounds in kimchi remain largely neglected. Here we show that kimchi contains a family of low-abundance (0.5–1.6 μg/g, dried weight) high-order indole oligomers derived from indole-3-carbinol (I3C), a breakdown product released from cruciferous vegetables used for producing the traditional subsidiary food. The structure determination of such complex molecules was accomplished by synthesizing linear indole oligomers as standard materials followed by the LC–HR–MS analysis. One indole tetramer (LTe2) is substantially toxic to tumor MV4-11 (IC 50 = 1.94 μM) and THP-1 cells (IC 50 = 7.12 μM). Collectively, the work adds valuable information to the knowledge package about kimchi, and may inspire the generation of indole-based molecules, to which many drugs belong.
研究领域:
食品科学
·
药物化学
·
分子生物学
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产品关联
DOI
PubMed
高影响因子
POLYMER BULLETIN
·
2020
·Vol. 78
·期 7
·3785-3801
·
IF 2.014
Ma Yu,Wang Lulu,Feng Ruijiang,Wang Jilin,Cai Tianzhou
In this study, we prepared a novel composite membrane (QCS-IRMOF-3) by attaching IRMOF-3 (metal–organic framework materials, formed by coordination of metallic zinc and 2-aminoterephthalic acid) with a free amino group to a quaternized chitosan (QCS) by chemical cross-linking. The successful synthesis of IRMOF-3 was verified by SEM, XRD, and FT-IR. Then, the mechanical properties, swelling properties, ion exchange capacity, hydroxide conductivity and chemical stability of the composite membrane (QCS-IRMOF-3) were also investigated. It was found that the performance of the aforementioned composite membrane was affected obviously by the amount of IRMOF-3 crystals. The composite membrane doped with 15 wt% IRMOF-3 crystals exhibits better overall performance, which included that the tensile strength is 22.4 MPa, water uptake is 78.4%, hydroxide conductivity is 29.9 mS cm −1 at 80 °C, and after immersion in 6.0 mol L −1 KOH solutions at 60 °C for about 240 h, only the conductivity decreased by less than 10%. This result implies that the composite membrane synthesized in this research is promising for application in alkaline polymer electrolyte fuel cells.
研究领域:
材料科学
·
燃料电池技术
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）