HIGH PERFORMANCE POLYMERS
·
2013
·
IF 0.85
Ling Xiao,Dechao Sun,Tianli Niu,Youwei Yao
Two novel phosphrous–nitrogen-containing flame retardants (3) and (4) were successfully synthesized from two steps: condensation reaction between 4-aminopenol and 1,4-phthaladehyde (or 4,4′-biphenyldicarboxaldehyde) and addition reaction between the above condensation compounds and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide. The structures of (3) and (4) were characterized by Fourier transform infrared, nuclear magnetic resonance, and mass spectroscopy methods. The results show that (3) and (4) can serve as co-curing agents of diaminodiphenylmethane (DDM) for the curing reaction of epoxy resin. The epoxy thermosets-containing DDM and (3) or (4) exhibit moderate changes in glass transition temperature, thermal stability, and show improvement in flame retardancy: UL94 V-0 grade can be obtained when phosphorus content of the epoxy thermoset is only 1.0%; the limiting oxygen index of epoxy resin system containing (4) reaches 40.9 when phosphorus content is up to 1.5%.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
COMPOSITES PART B-ENGINEERING
·
2019
·
IF 6.864
Zhenghong Guo,Zilu Wang,Zhengping Fang
Fullerene (C 60 ) is readily to capture chain radicals and delays the scission of macromolecular chains during the degradation or combustion of polymers, because of its high reactivity with free radicals. In this work, C 60 was functionalized with 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), trying to combine their free radical-trapping effects both in gaseous phase and in condensed phase. Through an addition reaction between C 60 and DOPO, DOPO has decorated onto the surface of C 60 via P–H bond at the molar ratio of 1:1. From the images of transmission electron micrographs (TEM) and scanning electron microscopy (SEM), the introduction of DOPO onto C 60 surface prevented C 60 from clumping together and achieved a looser morphology. Thermogravimetry (TG), differential scanning calorimetry (DSC) and cone calorimetry measurements showed that compared with pristine C 60 , DOPO- d -C 60 further increased the anti-oxidative properties and restrained the combustion process of polypropylene .
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 3
·49698
·
IF 2.52
Yao Xu,Jinhao Sun,Lijun Qian,Juan Li
Polydopamine (PDA) was prepared by using dopamine which has good charring ability. The PDA was used as an environmentally friendly flame retardant and combined with 9,10-dihydro-9-oxo-10-phosphaphenanthrene-10-oxide (DOPO) to improve the flame retardancy of epoxy (EP) resin. The flame retardancy and thermal stability of EP composites were researched by UL-94 vertical burning, limiting oxygen index (LOI), cone calorimetry tests, and thermal gravimetric analyzer. Adding DOPO alone requires 6% to make EP obtain the UL-94 V0. If DOPO and PDA are combined, only 4% is needed to make EP obtain the UL-94 V0, which suggests that there is good synergistic effect between them. Moreover, the peak of heat release rate of EP/DOPO/PDA composites is less than that of EP/DOPO composites. The reactions among EP, DOPO, and PDA reduce the release of combustible gases at the early stage of degradation; at the same time, DOPO volatilize to the gas phase, quench the free radicals, and the combustion can be stopped. In addition, due to the decrease of the amount of PDA/DOPO, the EP composite can get a higher glass transition temperature, but due to the aggregation of PDA in EP, the tensile property of EP composite decreases.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
ANALYTICA CHIMICA ACTA
·
2024
·
IF 5.7
Qi Xiao,Dandan Guo,Jing He,Min Zhang,Shan He,Shaohua Huang
Background In reversed-phase liquid chromatography , the C 18 alkyl bonded phase, as the primary stationary phase, is widely used in pharmaceutical and food analysis . The phenyl bonded phase often serves as a complementary choice to the C 18 phase to enhance the separation performance of specific categories of compounds. However, both C 18 and the currently available phenyl bonded phase chromatography columns show room for further optimization in improving the separation efficiency of specific compound classes, such as dihydroflavonoids. Additionally, the potential role and impact of introducing phosphorus groups into chromatographic stationary phases have not been fully explored, indicating a promising direction for research. Results In the present work, we prepared a novel phenyl stationary phase by bonding 9-oxa-10-phosphaphenanthrene 10-oxide onto silica gel . The obtained material was characterized by scanning electron microscopy, fourier transforms infrared spectroscopy , and elemental analysis . The results show that 9-oxa-10-phosphaphenanthrene 10-oxide was successfully bonded on the silica surface with a load of 3.90 %. Further chromatographic characterization in high-performance liquid chromatography exhibited high column efficiency (40,792 plates m-1 for the determination of biphenyl) and good stability (RSD of 0.28 %∼5.38 %). Moreover, we made a detailed study of the column separation mechanism by nuclear magnetic resonance spectroscopy titration experiment. Comparing to commercial phenyl column, the proposed stationary phase showed shorter retention time and higher throughput. In addition, the stationary phase has a strong ability to separate multiple types of compounds, which provides a new strategy for the separation of complex samples, such as active ingredients in traditional Chinese medicine . Significance We have developed a novel phenyl column and conducted a comprehensive examination of its chromatographic performance, demonstrating excellent separation capabilities and high efficiency for both nonpolar and moderately polar aromatic compounds . Additionally, we explored the impact of phosphorus-containing groups on the separation performance of chromatographic stationary phases.
研究领域:
分析化学
·
药物分析
✓ 已验证
DOI
PubMed
高影响因子
Results in Engineering
·
2023
·
IF 5
Tingting Dang,Miaomiao Gong,Bo Li,Guoqing Zhang,Xin Yang,Xu Wang,Daizong Han,Huiyong Chen
Three types of metal-doped ETS-10 zeolites including Ni-ETS-10, Al-ETS-10, and Ga-ETS-10 were successfully synthesized by one-pot template-free hydrothermal treatments. The effect of doping metals on the crystallinity, morphology, textural property, and basicity of the produced zeolites was systematically studied. It was found that doping with an appropriate amount of Ni could enhance the crystallinity and basicity of ETS-10 zeolites in comparison with Al and Ga, and the Ni species mainly existed in two forms of framework coordination and exchange site connection within Ni-ETS-10. The catalytic evaluation by the liquid Knoevenagel condensation reaction of benzaldehyde with ethyl cyanoacetate confirmed the superiority of ETS-10 and metal-doped ETS-10 in comparison with the contrast base zeolites of NaY and KY. And the 0.4Ni-ETS-10 catalyst exihibted the best performance with 75.6 % yield of ethyl ɑ-cyanocinnamate (ECC) among all the synthesized (metal-doped) ETS-10 zeolites. It is reasonable to expect that the demonstrated work has important implications for the design and facile synthesis of new-type high-performance base zeolite catalysts.
研究领域:
化学
·
催化
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
AMERICAN JOURNAL OF CHINESE MEDICINE
·
2023
·Vol. 51
·期 06
·1527-1546
·
IF 5.7
Cheng-Xi Li,Yu-Meng Wang,Wen-Jing Zhang,Shu Zhang,Jian-Ping Li,Tong Zhou,Jin-Ao Duan,Jian-Ming Guo
Inflammatory bowel disease (IBD) is a recurrent disease associated with a potential risk of colorectal cancer. Abelmoschus manihot (AM), a Chinese herbal medicine, is known to alleviate IBD. However, its mechanism of action requires further clarification. Here, we focused on the role of IL-10 and the gut microbiota in the mechanism of action of AM. The effects of AM on intestinal inflammation, mucus production, and gut microbes were evaluated in dextran sodium sulfate (DSS)-induced acute and chronic IBD models and in IL-10-deficient mice (IL-10 − ∕ − ). AM exhibited protective effects on acute and chronic models of IBD in wild-type mice by restoring body weight and colon length, promoting IL-10 secretion, and decreasing TNF- α levels. Moreover, AM alleviated inflammatory infiltration, increased mucin 2 transcription, and increased the number of goblet cells in the colon. On the contrary, these effects were diminished in IL-10 − ∕ − mice, which implied that the effect of AM on intestinal inflammation is IL-10-dependent. A gut microbial sequencing analysis showed that gut microbial dysbiosis was modulated by AM intervention. The regulatory effects of AM on Eggerthellaceae , Sutterellaceae , Erysipelotrichaceae , Burkholderiaceae , Desulfovibrionaceae , and Enterococcaceae were dependent on IL-10. These results revealed that AM ameliorated IBD and modulated gut microbes by promoting IL-10 secretion, indicating that AM has the potential to improve IBD and that AM is IL-10-dependent.
研究领域:
免疫学
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微生物学
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药理学
·
胃肠病学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PeerJ
·
2025
·
IF 2.4
Shuping Zhang,Zhenhua Liu,Jia Li,Qian Liu,Yongqing Zhang,Gaobin Pu
Background Geraniol 10-hydroxylase (G10H) is a cytochrome P450 monooxygenase involved in regulation, which is involved in the biosynthesis of monoterpene. However, G10H is not characterized at the enzymatic mechanism and regulatory function in Lonicera japonica . Methods and Results A gene related to the biosynthesis of monoterpenoid, geraniol 10-hydroxylase, has been cloned from the medicinal plant Lonicera japonica . The gene, LjG10H , encodes a peptide of 498 amino acids with a predicted molecular weight of 54.45 kDa. LjG10H shares a homology of 72.93–83.90% with G10H from other plants. Phylogenetic analysis suggests that the protein encoded by this gene belongs to the cytochrome P450 monooxygenase family. Tissue-specific expression analysis revealed that LjG10H is most highly expressed in flowers. Through heterologous expression in E. coli , the LjG10H protein was purified and its catalytic activity was studied. The results show that the enzyme can catalyze the hydroxylation of geraniol to 10-hydroxygeraniol. Additionally, analysis of Lonicera japonica seedlings with silenced LjG10H revealed a reduction in monoterpenoid content. Conclusions This study demonstrates that LjG10H plays an important role in the biosynthetic pathway of iridoids. This is the first article that ascribes G10H to be associated with the biosynthetic pathway of iridoid. This study provides a theoretical basis for the functional mechanism of LjG10H in regulating iridoid synthesis and provides a valuable resource for molecular breeding studies.
研究领域:
植物学
·
分子生物学
·
药用植物研究
✓ 已验证
产品关联
DOI
PubMed
高影响因子
METABOLIC ENGINEERING
·
2025
·
IF 6.8
Dan He,Yan Chen,Junfeng Shen,Han Yu,Jay D. Keasling,Xiaozhou Luo
10-hydroxy-2-decenoic acid (10-HDA), a unique unsaturated fatty acid present in royal jelly, has attracted considerable interest due to its potential medical applications. However, its low concentration in royal jelly and complex conformational structure present challenges for large-scale production. In this study, we designed and constructed a de novo biosynthetic pathway for 10-HDA in Escherichia coli . Initially, we introduced the heterologous thioesterase UaFatB1 to hydrolyze trans-2-decenoyl ACP to produce trans-2-decenoic acid, a key precursor for 10-HDA. Subsequently, we employed the bacterial cytochrome P450 enzyme CYP153AMaq to catalyze the terminal hydroxylation of trans-2-decenoic acid. Furthermore, through redox partner engineering and directed evolution, we identified the optimal combination for 10-HDA production: CYP153AMaq Q129R/V141L mutant with redox partner FdR0978/Fdx0338. Finally, we optimized the fermentation conditions and achieved a 10-HDA titer of 18.8 mg/L using glucose as primary carbon source. Our work establishes a platform for producing α , β -unsaturated fatty acids and their derivatives, facilitating further studies on these compounds.
研究领域:
生物化学
·
合成生物学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Acta Pharmaceutica Sinica B
·
2019
·
IF 5.808
Caifang Gao,Jianming Liang,Ying Zhu,Chengli Ling,Zhekang Cheng,Ruixiang Li,Jing Qin,Weigen Lu,Jianxin Wang
Chemotherapy outcomes for the treatment of glioma remains unsatisfactory due to the inefficient drug transport across the blood brain barrier (BBB) and insufficient drug accumulation in the tumor region. Although many approaches, including various nanosystems, have been developed to promote the distribution of chemotherapeutics in the brain tumor, the delivery efficiency and the possible damage to the normal brain function still greatly restrict the clinical application of the nanocarriers. Therefore, it is urgent and necessary to discover more safe and effective BBB penetration and glioma-targeting strategies. In the present study, menthol, one of the strongest BBB penetration enhancers screened from traditional Chinese medicine, was conjugated to casein, a natural food protein with brain targeting capability. Then the conjugate self-assembled into the nanoparticles to load anti-cancer drugs. The nanoparticles were characterized to have appropriate size, spheroid shape and high loading drug capacity. Tumor spheroid penetration experiments demonstrated that penetration ability of menthol-modified casein nanoparticles (M-CA-NP) into the tumor were much deeper than that of unmodified nanoparticles. In vivo imaging further verified that M-CA-NPs exhibited higher brain tumor distribution than unmodified nanoparticles. The median survival time of glioma-bearing mice treated with HCPT-M-CA-NPs was significantly prolonged than those treated with free HCPT or HCPT-CA-NPs. HE staining of the organs indicated the safety of the nanoparticles. Therefore, the study combined the advantages of traditional Chinese medicine strategy with modern delivery technology for brain targeting, and provide a safe and effective approach for glioma therapy.
研究领域:
药学
·
神经科学
·
肿瘤学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FLUID PHASE EQUILIBRIA
·
2015
·
IF 2.2
Liying Cai,Tingping Xie,Suying Zhao,Huidong Zheng,Dan Wu
The solubility of d -camphor-10-sulfonic acid (D-CSA, CAS No. 3144-16-9) in seven solvents (ethyl acetate, methyl acetate , n -butyl acetate, isopropyl acetate, glacial acetic acid, acetic anhydride and propionic acid) was measured under atmospheric pressure. The solubility data were correlated by the modified Apelblat equation, the λh equation, the Wilson model and the UNIQUAC model, respectively. And the thermodynamic parameters of D-CSA, molar dissolution enthalpy and entropy, were determined by the Van’t Hoff equation to explain its dissolving behavior in each solvent.
研究领域:
化学工程
·
物理化学
✓ 已验证
DOI
高影响因子
PETROLEUM SCIENCE AND TECHNOLOGY
·
2019
·
IF 1.07
Shuiquan Chen,Shuo Sun,Chaocheng Zhao,Qiyou Liu,Meng Zang
The biodesulfurization capacity of Gordonia sp. SC-10 in a biphasic reaction system was investigated in this study. Model oil containing dibenzothiophene was used as the sole sulfur source of bacterium. The results showed that 81.43% of the sulfur in model oil with initial sulfur content of 174 mg/l could be removed within 5 days. Gordonia sp. SC-10 had high desulfurization rate for model oils with low sulfur contents, which would reduce sulfur concentration to below 5 mg/l. Biodesulfurization process might be a potential method to obtain fuels with ultra-low sulfur contents.
研究领域:
环境生物学
·
微生物学
✓ 已验证
产品关联
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2024
·
IF 4.8
Van-Hien Pham,Bich-Ngoc Duong,Duy-Khoi Nguyen,Loc Ton-That,N.T. Dang,D. Thanh Khan,Ngoc-Quyen Tran,Ngoc Duy Nguyen,Van-Phuc Dinh
The synthesis of zeolite ETS-10 is strongly influenced by factors such as pH, the amount of the structure-directing agent, hydrothermal temperature and duration, which collectively affect the material’s morphology and structure. This study thoroughly investigates the effects of these parameters on the synthesis of ETS-10 zeolite using TiCl 3 and a waterglass solution. Characterization of the materials was performed through X-ray diffraction (XRD), scanning electron microscopy (SEM), infrared spectroscopy (FT-IR), and nitrogen isotherm adsorption-desorption at 77 K (BET-BJH) techniques. The findings indicate that pH and the structure-directing agent significantly influenced the phase composition , while hydrothermal temperature predominantly determined the crystallization rate of ETS-10. Optimal synthesis conditions were established at an initial pH of 11, employing 0.3 g of the structure-directing agent and conducting hydrothermal crystallization at 230 °C for 24 h. Under these conditions, the ETS-10 zeolite produced exhibited a high surface area of 300.1 m 2 /g, making it effective in removing Pb 2+ ions from solution. In particular, when tested under optimal conditions (pH 5) for 600 min, Pb (II) adsorption by ETS-10 reached a maximum uptake capacity of 956.19 mg/g, as determined by the Langmuir isotherm model. This capacity surpasses that of as-synthesized ETS-10 prepared from alternative Ti sources and other materials used in previous studies on Pb(II) adsorption.
研究领域:
环境科学
·
材料科学
✓ 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）