POLYMER
·
2016
·
IF 3.586
Qinzhuo Zhou,Anqi Wang,Lu Dai,Suyun Jie,Bo-Geng Li
A series of hydroxyl functionalized polybutadienes has been prepared by combining the oxidolysis and reduction of cis -polybutadiene rubber (BR). For the first time, multi-hydroxyl polybutadiene (MHPB) with α,ω- and intrachain hydroxyl groups was synthesized through the simultaneous reduction of –CHO and epoxy groups in epoxidized aldehyde group terminated polybutadiene (EATPB) by sodium dihydro-bis-(2-methoxyethoxy) aluminate (Red-Al). The corresponding hydroxyl functionalized polyethylenes , including hydroxyl-terminated polyethylene (HTPE), multi-hydroxyl polyethylene (MHPE) and hydroxyl-terminated polyethylene with ethyl branches (FHTPE), were readily obtained via the hydrogenation of C=C double bonds in the functionalized polybutadienes with TSH/TPA regents. The microstructures of all the products were confirmed by 1 H NMR, 13 C NMR and FT-IR, and their thermal properties were determined by TGA and DSC . It has been indicated that the linear HTPE and MHPE possessed high initial thermal degradation temperature, high degree of crystallinity , and high melting temperature due to their stereoregular microstructure. However, the FHTPE obtained through the hydrogenation of HTPB from free radical polymerization had much lower degree of crystallinity and melting temperature due to the presence of more ethyl branches.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Omega
·
2023
·
IF 4.1
Yajie Zuo,Siying Zhu,Yi Liu,Jingjing Zhao,Shiyi Zhang,Chongmin Zhong
Efficient O-alkylation of phenols and carboxylic acids has essential applications in organic synthesis. A mild alkylation method for phenolic and carboxylic OH groups is developed using alkyl halides as alkylation reagents and tetrabutylammonium hydroxide as a base, and lignin monomers can be fully methylated in quantitative yields. Additionally, phenolic and carboxylic OH groups can be alkylated by different alkyl halides in one pot in different solvent systems.
研究领域:
有机化学
·
合成化学
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产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Xueni Zhao,Guowen Shi,Linlin Ma,Jinxin Guan,Zhipeng Zhu
Carbon fiber (CF) is one of ideal reinforcements to hydroxyapatite (HA) owing to its unique structure, excellent biocompatibility and high mechanical properties. However, the mechanical property of CF reinforced HA (CF/HA) composites cannot be effectively improved due to the mismatch in surface properties and thermal expansion coefficients between CF and HA. In order to solve the problems, nano-hydroxyapatite (nHA) coating with different thickness was fabricated on the CF surface. The effect of the coating thickness on mechanical property of nHA-coated CF/HA composites was studied by finite element analysis. The CF with proper nHA coating thickness was subsequently used to reinforce HA. The compressive strength of nHA-coated CF/HA composites was approximately 97.3 % and 164.6 % higher than those of the uncoated CF/HA composites and pure HA ceramics, respectively. The interface properties and crack propagation were analyzed by cohesive element in the finite element analysis. The toughening mechanism of the composites included interfacial debonding, crack deflection, crack branching, and crack bridging. The mechanical properties of nHA-coated CF/HA composites were enhanced due to the strong interfacial bonding strength and reducing cracking in HA matrix. The prepared nHA-coated CF/HA composites satisfy the requirement of the mechanical properties of human load-bearing bone. It can be used to prepare cages, plates, screws, pins and other compact bone substitute parts in bone grafting. The study provided a method for construction of nHA-coated CF/HA composites with the designed properties by adjusting the nHA coating on the fiber and can be used to design other fibers reinforced ceramic matrix composites.
研究领域:
生物医学工程
·
材料科学
✓ 已验证
DOI
高影响因子
MICROCHIMICA ACTA
·
2019
·Vol. 186
·期 11
·1-9
·
IF 5.479
Xue Jin-Hua,Liu Ling,Wang Yong-Sheng,Li Jia-Qian,Li Mei,Qu Yue-Ning,Li Le
This work describes a method for the determination of 1-hydroxypyrene (OH-Py) via aggregation-induced quenching of the emission of protamine-coated gold nanoclusters using 9-hydroxyphenanthrene (OH-Phe) as a sensitizer to boost the emission efficiency of nanoprobe. Under optimum conditions, the drop in fluorescence intensity at excitation/emission wavelengths of 300/596 nm is proportional to the concentrations of OH-Py in the range from 1.0 to 65 nM. The relative standard deviations are 4.2, 2.4 and 1.9% (for n = 11) at concentration levels of 8.0, 32 and 48 nM of OH-Py, respectively. The detection limit is 0.3 nM which is much lower than that of some previously reported methods. The recoveries from urine samples spiked with OH-Py ranged between 94.4 and 98.8%.
1-Hydroxypyrene (OH-Py) can trigger the aggregation of protamine-gold nanoclusters (PRT-AuNCs), resulting in the emission quenching of PRT-AuNCs. 9-Hydroxyphenanthrene (OH-Phe) can boost the emission efficiency of nanoprobe. Thereby, a highly sensitive assay of OH-Py was established.
研究领域:
分析化学
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环境医学
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纳米生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Sciences
·
2025
·
IF 6.3
Jin Chen,Yiwei Fang,Borui Sun,Ying Xu,Wanyi Chen,Kai zhao,Huiping Zhang
Polycyclic aromatic hydrocarbons (PAHs) are widespread pollutants from incomplete combustion of organic materials, linked to various health issues and pregnancy complications. This study explored the relationship between PAH metabolites and gestational hypertension. Urine samples from 118 normal pregnant women and 40 with gestational hypertension were analyzed. In vitro experiments using human trophoblast cells (HTR-8/SVneo) exposed to these metabolites assessed their effects on cellular metabolism. Comprehensive metabolomics analysis was performed using Tidymass and DRomics to integrate global and dose-response metabolomics data. Results showed higher levels of 1-hydroxypyrene (1-OHPYR) and 9-Hydroxyphenanthrene (9-OHPHE) linked to gestational hypertension, inhibiting trophoblast cell invasion and migration. Identified markers include Isobutyryl-L-carnitine, methyl-3-hydroxybutyric acid, threonine, and glutamic acid for 1-OHPYR, and phosphocreatine for 9-OHPHE. This study highlights the connection between PAH metabolites and gestational hypertension, suggesting potential biomarkers and mechanisms. Future research should confirm these findings and explore prevention and treatment strategies.
研究领域:
环境健康
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生殖医学
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代谢组学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SYNTHESIS-STUTTGART
·
2015
·Vol. 47
·期 23
·3751-3757
·
IF 2.689
Zhijie Li,Quan Wen,Lihong Zhou,Xingmei Deng,Qingle Zeng
The synthesis of highly important α-hydroxycarboxylic acid anilides via copper-catalyzed chemoselective C–N coupling reactions of α-hydroxyamides and aryl halides is described. This highly selective N-arylation process demonstrates wide substrate scope, cost savings and easy operation. In addition, the chirality of l-3-phenyllactamide is preserved during the reaction.
研究领域:
有机化学
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合成化学
✓ 已验证
DOI
高影响因子
Food & Function
·
2019
·Vol. 10
·期 11
·7052-7062
·
IF 3.241
Lukai Ma,Guoqin Liu,Weiwei Cheng,Xinqi Liu,Huifan Liu,Qin Wang
In this study, the formation of two toxic reactive aldehydes, 4-hydroxy-2-hexenal (HHE) and 4-hydroxy-2-nonenal (HNE), was investigated during frying of two different foodstuffs at 180 °C for 7 h in three different vegetable oils. The results showed that HHE and HNE content in the oil after frying was lower than that in the oil fried without foods. It was mainly because of the incorporation of HHE/HNE into the fried foods. In French Fries (FF), the HNE content was higher, whereas it was lower in the fried chicken breast meat (FCBM). The bidirectional model systems consisting of the model oil frying system and the model food frying system were used. The result of the model oil system showed that the content of HNE was higher in FF for the higher hydrophobic property than that in HHE, which would be preferably bounded into the hydrophobic helical structures, whereas the lower content of HNE was observed in FCBM due to its higher reactivity towards the nucleophilic group, namely, the protein in FCBM. Furthermore, the model food frying system including starch and protein extracted from the corresponding foodstuffs verified the results in the model oil system. Finally, the probable migration mechanism of HHE and HNE in different food matrices was proposed for the first time.
研究领域:
食品科学
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毒理学
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生物化学
✓ 已验证
DOI
PubMed
高影响因子
Materials
·
2020
·Vol. 13
·期 12
·2793
·
IF 3.057
Tomasz Witko,Daria Solarz,Karolina Feliksiak,Katarzyna Haraźna,Zenon Rajfur,Maciej Guzik
Two bio-based polymers have been compared in this study, namely: polylactide (PLA) and polyhydroxyoctanoate (PHO). Due to their properties such as biocompatibility, and biointegrity they are considered to be valuable materials for medical purposes, i.e., creating scaffolds or wound dressings. Presented biopolymers were investigated for their impact on cellular migration strategies of mouse embryonic fibroblasts (MEF) 3T3 cell line. Advanced microscopic techniques, including confocal microscopy and immunofluorescent protocols, enabled the thorough analysis of the cell shape and migration. Application of wound healing assay combined with dedicated software allowed us to perform quantitative analysis of wound closure dynamics. The outcome of the experiments demonstrated that the wound closure dynamics for PLA differs from PHO. Single fibroblasts grown on PLA moved 1.5-fold faster, than those migrating on the PHO surface. However, when a layer of cells was considered, the wound closure was by 4.1 h faster for PHO material. The accomplished work confirms the potential of PLA and PHO as excellent candidates for medical applications, due to their properties that propagate cell migration, vitality, and proliferation—essential cell processes in the healing of damaged tissues.Keywords:wound healing;actin;migration;polyhydroxyalkanoates;polyhdroxyoctanoate;polylactide
研究领域:
生物医学工程
·
细胞生物学
✓ 已验证
DOI
PubMed
高影响因子
Desalination and Water Treatment
·
2024
·
IF 1
Yuan Ziwei,Wang Zhe,Wang Shaopo,Yu Jingjie,Li Chen,Chang Jing
Transition metal hydroxyl oxides have been used widely as ozone catalysts for water purification. However, the fabrication methods selected and the pollutants treated vary, making it difficult to compare their performance. In this study, ZnOOH, FeOOH, CoOOH, and MnOOH were synthesized by the same method to remove multiple structurally similar targets. Results showed that the ZnOOH performed the best, removing over 90 % of all targets within 40 min, and presenting the highest ozone utilization rate of 0.081 min −1 . Multiple ROS quantification and contribution experiments jointly demonstrated that ZnOOH had an advantage over the other catalysts only n ·OH generation, but the·OH contributed 93 % of target removal in the ZnOOH/O 3 process. Structure analysis of ZnOOH suggested that its·OH generation had little connection with the contents of surface metal and adsorbed water, but was dependent on the surface structural hydroxyl that would undergo loss at 100–300℃. This concentration of ZnOOH was 10.1 mM/g, which was 1.7, 5.3, and 6.3 times higher than that of FeOOH, CoOOH, and MnOOH, respectively. Heat treatment further revealed that these surface hydroxyl mainly originated from the hydroxyl ions from water dissociation and could regenerate timely during reuse. Finally, a possible catalysis pathway was proposed.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
Arabian Journal of Chemistry
·
2017
·
IF 4.553
Waqar Uddin,Gang Hu,Xuanxuan Sun,Hui Zhang,Yegui Wang,Lin Hu
A novel method for identification of two aromatic isomers of mono hydroxy benzoic acid (HBA) was reported by using their different perturbation effects on the potential oscillations of a Belousov-Zhabotinsky (BZ) system. In such a system, a macrocyclic complex of Cu [CuL](ClO 4 ) 2 was used as catalyst in which ligand L is 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradeca-4,11-diene. To the BZ system, 3-hydroxy benzoic acid (3-HBA) could temporarily quench and regenerate potential oscillations with damping characters after inhibition time (t in ) while 4-hydroxy benzoic acid (4-HBA) could only change the oscillation amplitude (ΔA) to give damping oscillations with no inhibition time. Thus, these two isomers of HBA were identified. Reaction mechanisms of BZ have been proposed by FKN model. An explanation of perturbation mechanism is that, although 3-HBA reacted with BrO 2 while 4-HBA reacted with BrO 3 − , they all produced 1,4-quinone.
研究领域:
化学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF STEROID BIOCHEMISTRY AND MOLECULAR BIOLOGY
·
2019
·
IF 3.785
Runlan Wan,Xi Kong,Youzhe Yang,Siwen Tao,Youyou Chen,Alexander Tobias Teichmann,Frank Heinrich Wieland
The clinical use of the steroidal aromatase inhibitor Formestane (4-hydroxandrostenedione, 4-OHA) in the treatment of advanced ER+ breast cancer has been discontinued, and therefore, interest in this remarkable drug has vanished. As a C-19 sterol, 4-OHA can undergo extensive intracellular metabolism depending on the expression of specific enzymes in the corresponding cells. We used the metabolites 4β-hydroxyandrosterone, 4β-hydroxyepiandrosterone and its 17β-reduced derivative as standards for the proof of catalytic activity present in the cell culture medium and expressed by the isolated enzymes. All of the aldo-keto reductases AKR1C1, AKR1C2, AKR1C3 and AKR1C4 catalysed the reduction of the 3-keto-group and the Δ 4,5 double bond of 4-OHA at the same time. Molecular docking experiments using microscale thermophoresis and the examination of the kinetic behaviour of the isolated enzymes with the substrate 4-OHA proved that AKR1C3 had the highest affinity for the substrate, whereas AKR1C1 was the most efficient enzyme. Both enzymes (AKR1C1and AKR1C3) are highly expressed in adipose tissue and lungs, exhibiting 3β-HSD activity. The possibility that 4-OHA generates biologically active derivatives such as the androgen 4-hydroxytestosterone or some 17β-hydroxy derivatives of the 5α-reduced metabolites may reawaken interest in Formestane, provided that a suitable method of administration can be developed, avoiding oral or intramuscular depot-injection administration.
研究领域:
药理学
·
生物化学
·
肿瘤学
·
分子生物学
·
酶学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Current Research in Food Science
·
2023
·
IF 6.3
Shiye Lin,Jesus Simal-Gandara,Hui Cao,Jianbo Xiao
Polyhydroxy flavonols readily degraded during thermal processing. In this study, the UPLC-Q-tof-MS/MS was applied to explore the stability of dietary polyhydroxy flavonols, myricetin, kaempferol, galangin, fisetin, myricitrin, quercitrin and rutin, in boiling water. The decomposition of flavonols was mainly caused by the heterocyclic ring C opening to form simpler aromatic compounds. The degradation products mainly included 1,3,5-benzenetriol, 3,4,5-trihydroxybenzoic acid, 2,4,6-trihydroxybenzoic acid and 2,4,6-trihydroxybenzaldehyde, etc. Compared with myricetin with a pyrogallol-type structure on the ring B, the glycoside in myricitrin slightly affects the stability. However, the glycosides in rutin and quercitrin dramatically improved the stability in water. During the boiling process, flavonols underwent a series of chemical reactions, such as hydroxylation, dehydroxylation, deglycosidation, deprotonation, and C-ring cleavage.
研究领域:
食品科学
·
分析化学
·
植物化学
✓ 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）