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Mitigating ethyl carbamate production in Chinese rice wine:Role of raspberry extract
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作者 Yuxin Liu Chi Shen +7 位作者 Xiaoyu Wang Chaogeng Xiao Zisheng Luo Guochang Sun Wenjing Lu Rungang Tian Lijia Dong Xueyuan Han 《Journal of Integrative Agriculture》 2025年第1期353-365,共13页
This study investigated the use of raspberry extract(RBE) for mitigating ethyl carbamate(EC) accumulation in Chinese rice wine(Huangjiu), a traditional fermented beverage. It focused on the addition of RBE to the ferm... This study investigated the use of raspberry extract(RBE) for mitigating ethyl carbamate(EC) accumulation in Chinese rice wine(Huangjiu), a traditional fermented beverage. It focused on the addition of RBE to the fermentation mash and its effects on EC levels. The results showed a significant reduction in EC production that could be attributed to RBE's role in altering urea and citrulline catabolism and inhibiting arginine metabolism, thus preventing EC precursors from reacting with ethanol. Additionally, RBE enhanced the rice wine's flavor profile, as shown by volatile component and amino acid analysis. This study also explored RBE's impact on the metabolism of arginine by Saccharomyces cerevisiae in a simulated fermentation environment, and found increased arginine, reduced urea and citrulline levels, altered enzyme activities, and gene expression changes in the arginine metabolism and transport pathways. In conclusion, the results clearly demonstrated RBE's efficacy in reducing the EC content in Chinese rice wine, offering valuable insights for EC reduction strategies. 展开更多
关键词 Chinese rice wine ethyl carbamate raspberry extract Saccharomyces cerevisiae arginine metabolism
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Ethyl acetate fraction of Sargassum pallidum extract attenuates particulate matter-induced oxidative stress and inflammation in keratinocytes and zebrafish 被引量:1
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作者 Wook Chul Kim Ji-Won Park +3 位作者 Bohyun Yun WonWoo Lee Kyung-Min Choi Seung-Hong Lee 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2024年第4期137-146,共10页
Objective:To evaluate the effect of the ethyl acetate fraction derived from Sargassum pallidum extract against particulate matter(PM)-induced oxidative stress and inflammation in HaCaT cells and zebrafish.Methods:HaCa... Objective:To evaluate the effect of the ethyl acetate fraction derived from Sargassum pallidum extract against particulate matter(PM)-induced oxidative stress and inflammation in HaCaT cells and zebrafish.Methods:HaCaT cells and zebrafish were used to evaluate the protective effects of the ethyl acetate fraction of Sargassum pallidum extract against PM-induced oxidative stress and inflammation.The production of nitric oxide(NO),intracellular ROS,prostaglandin E_(2)(PGE_(2)),and pro-inflammatory cytokines,and the expression levels of COX-2,iNOS,and NF-κB were evaluated in PM-induced HaCaT cells.Furthermore,the levels of ROS,NO,and lipid peroxidation were assessed in the PM-exposed zebrafish model.Results:The ethyl acetate fraction of Sargassum pallidum extract significantly decreased the production of NO,intracellular ROS,and PGE_(2) in PM-induced HaCaT cells.In addition,the fraction markedly suppressed the levels of pro-inflammatory cytokines and inhibited the expression levels of COX-2,iNOS,and NF-κB.Furthermore,it displayed remarkable protective effects against PM-induced inflammatory response and oxidative stress,represented by the reduction of NO,ROS,and lipid peroxidation in zebrafish.Conclusions:The ethyl acetate fraction of Sargassum pallidum extract exhibits a protective effect against PM-induced oxidative stress and inflammation both in vitro and in vivo and has the potential as a candidate for the development of pharmaceutical and cosmeceutical products. 展开更多
关键词 Particulate matter INFLAMMATION Oxidative stress Sargassum pallidum ethyl acetate fraction ZEBRAFISH
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STRUCTURE OF THERMOTROPIC LIQUID CRYSTALLINE VANILLIC ACID/P-HYDROXYBENZOIC ACID/ETHYLENE TEREPHTHALATE VHE TERPOLYESTERS
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作者 Xin Gui LI Mei Rong HUANG +1 位作者 Gui He GUAN Tong SUN 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第3期207-210,共4页
Thermotropic liquid crystalline VHE terpolyesters made from vanillic acid (V),p-hydroxybenzoic acid (H) and poly(ethylene terephthalate) (E) were studied by 400 MHz NMR spectra, wide angle X-ray diffraction,scanning e... Thermotropic liquid crystalline VHE terpolyesters made from vanillic acid (V),p-hydroxybenzoic acid (H) and poly(ethylene terephthalate) (E) were studied by 400 MHz NMR spectra, wide angle X-ray diffraction,scanning electron and polarizing microscopes.It was found that the VHE terpolyesters had random sequence distribution.The VHE terpolyester films exhibited highly oriented fibrillar structure. 展开更多
关键词 ACID STRUCTURE OF THERMOTROPIC LIQUID CRYSTALLINE VANILLIC ACID/p-hydroxybenzoIC ACID/ethylENE TEREPHTHALATE VHE TERPOLYESTERS OC MHZ
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Tailoring Ni based catalysts by indium for the dehydrogenative coupling of ethanol into ethyl acetate
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作者 Ming Yin Jifeng Pang +4 位作者 Jin Guo Xianquan Li Yujia Zhao Pengfei Wu Mingyuan Zheng 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第8期1321-1331,共11页
Exploring stable and robust catalysts to replace the current toxic CuCr based catalysts for dehydrogenative coupling of ethanol to ethyl acetate is a challenging but promising task.Herein,novel NiIn based catalysts we... Exploring stable and robust catalysts to replace the current toxic CuCr based catalysts for dehydrogenative coupling of ethanol to ethyl acetate is a challenging but promising task.Herein,novel NiIn based catalysts were developed by tailoring Ni catalysts with Indium(In)for this reaction.Over the optimal Ni0.1Zn0.7Al0.3InOx catalyst,the ethyl acetate selectivity reached 90.1%at 46.2%ethanol conversion under the conditions of 548 K and a weight hourly space velocity of 1.9 h^(-1)in the 370 h time on stream.Moreover,the ethyl acetate productivity surpassed 1.1 g_(ethyl acetate)g_(catalyst)^(-1)h^(-1),,one of the best performance in current works.According to catalyst characterizations and conditional experiments,the active sites for dehydrogenative coupling of ethanol to ethyl acetate were proved to be Ni4In alloys.The presence of In tailored the chemical properties of Ni,and subsequently inhibited the C-C cracking and/or condensation reactions during ethanol conversions.Over Ni4In alloy sites,ethanol was dehydrogenated into acetaldehyde,and then transformed into acetyl species with the removal of H atoms.Finally,the coupling between acetyl species and surface-abundant ethoxyde species into ethyl acetate was achieved,affording a high ethyl acetate selectivity and catalyst stability. 展开更多
关键词 Dehydrogenative coupling ETHANOL ethyl acetate Nickel and indium alloys
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Syntheses,structures,and properties of three coordination polymers based on 5⁃ethylpyridine⁃2,3⁃dicarboxylic acid and N⁃containing ligands
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作者 TANG Long BIAN Yaxin +3 位作者 CHEN Luyuan HOU Xiangyang WANG Xiao WANG Jijiang 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第10期1975-1985,共11页
Three coordination polymers[Mn(epda)(2,2'⁃bipy)(H_(2)O)](1),[Mn(epda)(phen)](2),and[Co_(2)(epda)2(bpe)2(H_(2)O)_(4)]·5H_(2)O(3)(H2epda=5⁃ethyl⁃pyridine⁃2,3⁃dicarboxylic acid,2,2'⁃bipy=2,2'⁃bipyridine,... Three coordination polymers[Mn(epda)(2,2'⁃bipy)(H_(2)O)](1),[Mn(epda)(phen)](2),and[Co_(2)(epda)2(bpe)2(H_(2)O)_(4)]·5H_(2)O(3)(H2epda=5⁃ethyl⁃pyridine⁃2,3⁃dicarboxylic acid,2,2'⁃bipy=2,2'⁃bipyridine,phen=phenanthroline,bpe=1,2⁃bis(4⁃pyridyl)ethylene)were synthesized by solvothermal reactions and characterized by single⁃crystal X⁃ray diffraction,thermogravimetric analyses,IR spectroscopy and elemental analysis.1 displays a 1D chain struc⁃ture,and these chains are joined by O-H…O hydrogen bonding andπ⁃πstacking interactions to generate a 2D layer structure.2 displays a 2D layer structure,and adjacent layers are generated 3D architecture throughπ⁃πstacking interactions.3 displays a 1D chain structure,and adjacent chains are generated double layer structure through O-H…O hydrogen bonding.The fluorescent properties of 1 and 3 indicate that they can potentially be used as a luminescent sensor.1 was highly selective and sensitive towards o⁃nitrophenol through different detection mechanisms,however,3 was highly selective and sensitive towards 2,4,6⁃trinitrophenol.In addition,the magnetic behavior of 2 has also been investigated.CCDC:2172533,1,2355773,2,2355774,3. 展开更多
关键词 coordination polymers 5⁃ethyl⁃pyridine⁃2 3⁃dicarboxylate ligand crystal structures fluorescent properties magnetic behavior
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高电压正极材料LiFe_(0.06)Ni_(0.94)PO_(4)/C的制备及其性能研究
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作者 李志义 孙赫 +3 位作者 孙海礼 魏炜 刘凤霞 刘志军 《现代化工》 CAS 北大核心 2025年第1期184-189,共6页
磷酸镍锂(LiNiPO_(4))是一种具有5.1 V高电压平台的橄榄石类锂离子电池正极材料,由于较低的电导率和实际放电比容量限制了其实际应用。为了制备纯相LiNiPO_(4),考察了不同摩尔比表面活性剂油胺对LiNiPO_(4)的影响,油胺添加摩尔比[n(油胺... 磷酸镍锂(LiNiPO_(4))是一种具有5.1 V高电压平台的橄榄石类锂离子电池正极材料,由于较低的电导率和实际放电比容量限制了其实际应用。为了制备纯相LiNiPO_(4),考察了不同摩尔比表面活性剂油胺对LiNiPO_(4)的影响,油胺添加摩尔比[n(油胺)∶n(金属)]为10∶1制备的材料结晶度最佳,经过煅烧工艺参数优化成功获得纯相LiNiPO_(4)。为了改善LiNiPO_(4)的电化学性能,首次采用乙基纤维素为碳源制备的掺有Fe摩尔分数为6%的LiFe_(0.06)Ni_(0.94)PO_(4)/C并将其电化学性能与纯相LiNiPO_(4)进行比较,结果表明,采用乙基纤维素制备的LiFe_(0.06)Ni_(0.94)PO_(4)/C具有更大的初始放电比容量、更小的电荷转移电阻,其中10%乙基纤维素添加量的样品电化学性能最佳。 展开更多
关键词 磷酸镍锂 油胺 乙基纤维素 碳包覆 电化学性能
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Preparation of Ni(HCO_3)_2 and its catalytic performance in synthesis of benzoin ethyl ether 被引量:1
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作者 吴旭 安霞 谢鲜梅 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第5期1440-1445,共6页
Ni(HCO3)2 with unique phase and high crystallinity was synthesized with urea hydrolysis. The as-prepared samples were well characterized in detail. N2 adsorption and desorption result manifests a high surface area o... Ni(HCO3)2 with unique phase and high crystallinity was synthesized with urea hydrolysis. The as-prepared samples were well characterized in detail. N2 adsorption and desorption result manifests a high surface area of 99.03 m2/g with a pore size of 7.8 nm. Scanning electron microscopy (SEM) and particle size distribution reveal that the diameters of the formed pellets are uniform. Thermogravimetry (TG) analysis result shows that 500 ℃ could be the appropriate temperature for converting Ni(HCO3)2 precursors into NiO via a thermal decomposition process. CO2 and NH3 temperature-programmed desorption results show that Ni(HCO3)2 has explicit acid-base sites. Transmission electron microscopy (TEM) results vividly indicate that the pellets are aggregated by hexagonal platelets and possess porous structures. Ni(HCO3)2 can efficiently catalyze the one-step synthesis of benzoin ethyl ether from benzaldehyde and ethanol, with the conversion ofbenzaldehyde up to 57.5% and nearly 100% selectivity of benzoin ethyl ether. 展开更多
关键词 Ni(HCO3)2 CATALYSIS green synthesis benzoin ethyl ether
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氮肥和Trinexapac-ethyl配合施用对草地早熟禾草坪生长的影响 被引量:4
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作者 王晓英 呼天明 +3 位作者 王佺珍 田立民 张晓玲 田凯 《中国农业科学》 CAS CSCD 北大核心 2008年第11期3679-3684,共6页
【目的】探明氮肥和Trinexapac-ethyl(TE)配合施用对草地早熟禾草坪生长的影响。【方法】在草地早熟禾返青后,采用完全随机区组设计,氮肥设0(N1)、20(N2)、25(N3)和30(N4)kg·ha-14个水平,每月施1次;TE设0(T1)、312.5(T2)和625(T3)m... 【目的】探明氮肥和Trinexapac-ethyl(TE)配合施用对草地早熟禾草坪生长的影响。【方法】在草地早熟禾返青后,采用完全随机区组设计,氮肥设0(N1)、20(N2)、25(N3)和30(N4)kg·ha-14个水平,每月施1次;TE设0(T1)、312.5(T2)和625(T3)ml·ha-13个水平,每10d喷施1次,测定氮肥和TE配合施用对草坪株高、产草量及叶绿素含量的影响。【结果】施氮能显著促进草坪生长,而喷施TE能够显著抑制草坪的生长。在不同的氮肥水平上,T2处理能够降低草坪新增株高、剪草量达30%左右,T3处理能够降低草坪新增株高、剪草量达45%左右。在保证正常需要的同时,N2T3、N3T3、N4T3处理的草坪生长较慢。氮与TE的交互作用对草坪颜色有极显著影响;相同氮水平处理中,T3处理草坪草叶绿素含量显著高于T1处理;N4T3处理草坪颜色最深。【结论】以草坪生长与叶绿素含量为评判的依据,最好的组合为N2T3、N4T3,它们均能使草坪生长减慢而且颜色加深。 展开更多
关键词 氮肥 抗倒酯(Trinexapac-ethyl) 草地早熟禾
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MCPB-ethyl对富士苹果疏花效果的研究 被引量:8
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作者 曹秋芬 孟玉平 +1 位作者 横田清 王晋泽 《华北农学报》 CSCD 北大核心 2004年第2期100-103,共4页
探讨了MCPB-ethyl的喷布时期、喷布浓度对富士苹果的疏花效果、果实发育和果实品质的影响。试验证明,MCPB-ethyl是一个良好的苹果疏花剂,有效喷布期是中心花盛开后1-5 d,最适喷布期是中心花盛开后1-3 d;最适喷布浓度为15 mol/L,对果实... 探讨了MCPB-ethyl的喷布时期、喷布浓度对富士苹果的疏花效果、果实发育和果实品质的影响。试验证明,MCPB-ethyl是一个良好的苹果疏花剂,有效喷布期是中心花盛开后1-5 d,最适喷布期是中心花盛开后1-3 d;最适喷布浓度为15 mol/L,对果实发育、果形、果实着色和果实品质无不利影响。 展开更多
关键词 富士苹果 疏花剂 MCPB-ethyl 喷布时期 果实品质
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降解氨基甲酸乙酯的酯酶挖掘及酶学性质表征
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作者 刘庆涛 朱司宝 +5 位作者 王天文 李闯 钱森和 张温清 程凡 田淑芳 《食品科学》 EI CAS 北大核心 2025年第2期99-107,共9页
本研究在NCBI数据库中挖掘出4个在pH 4.5及7.0条件下均具有氨基甲酸乙酯(ethyl carbamate,EC)降解能力的酯酶(ES1、ES5、ES8和ES9),实现它们在大肠杆菌中的可溶性表达,并对其进行纯化及酶学性质表征。结果表明,ES1、ES5、ES8和ES9最适... 本研究在NCBI数据库中挖掘出4个在pH 4.5及7.0条件下均具有氨基甲酸乙酯(ethyl carbamate,EC)降解能力的酯酶(ES1、ES5、ES8和ES9),实现它们在大肠杆菌中的可溶性表达,并对其进行纯化及酶学性质表征。结果表明,ES1、ES5、ES8和ES9最适温度分别为70、70、55℃及55℃,ES1、ES5、ES9最适pH值呈碱性,ES8呈中性;4种酶在温度高于45℃或pH值低于5.0条件下稳定性显著降低;4种酶的活性受到Fe^(3+)、Co^(2+)、Cu^(2+)的强烈抑制;4种酶在体积分数10%乙醇存在条件下,可分别保持50.48%、48.44%、42.60%及33.59%的酶活力。4种酶在质量分数为5%NaCl条件下,可分别保持24.09%、20.41%、16.11%及10.73%的酶活力。4种酶在pH 4.5条件下对EC的米氏常数(Km)值分别为210.7、213.8、256.2 mmol/L及127.2 mmol/L,催化常数(kcat)/米氏常数(Km)值分别为214.31、203.20、161.46 L/(mol·s)及257.43 L/(mol·s)。结构分析推测,ES9底物通道入口较窄,可能影响EC的进入,从而影响ES9对EC的最大反应速率;而ES9具有相对较高的EC亲和力,可能归因于ES9与EC之间较强的氢键作用力。本研究获得了具有良好乙醇耐受性及EC水解性能的酯酶,丰富了EC水解酶酶库,为未来控制低酒精度的传统发酵食品中EC含量提供了新方法。 展开更多
关键词 氨基甲酸乙酯 氨基甲酸乙酯水解酶 酯酶 传统发酵食品 食品安全
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Trinexapac-ethyl、Prohexad ione-Ca在草坪化学控制中的应用研究 被引量:11
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作者 杨代斌 袁会珠 +2 位作者 覃兆海 何源 王淑芝 《草地学报》 CAS CSCD 2005年第4期304-307,共4页
为探明Trinexapac-ethyl和Prohexadione-Ca用于草坪化学控制的可行性,研究了其对高羊茅(Festuca arundinacea)生长发育的影响.结果显示:使用剂量高于0.095 kg/hm2时, Trinexapac-ethyl对高羊茅具有明显的矮化作用,在0.36 kg/hm2剂量下Pr... 为探明Trinexapac-ethyl和Prohexadione-Ca用于草坪化学控制的可行性,研究了其对高羊茅(Festuca arundinacea)生长发育的影响.结果显示:使用剂量高于0.095 kg/hm2时, Trinexapac-ethyl对高羊茅具有明显的矮化作用,在0.36 kg/hm2剂量下Prohexadione-Ca的抑制率可达95.2%;Trinexapac-ethyl和Prohexadione-Ca都能使植株新增鲜重显著降低,但对新增干重影响很小,Trinexapac-ethyl对植株新增干重无影响;在施用Trinexapac-ethyl的情况下,随着留茬高度的增加新增株高减少,合理留茬高度为4~6 cm;Trinexapac-ethyl和Prohexadione-Ca可以有效降低株高,从而减少草坪修剪次数. 展开更多
关键词 Trinexapac-ethyl Prohexadione-Ca 化学控制 生长抑制剂 草坪草 高羊茅
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雷帕霉素产生菌突变株FC904-107发酵产生7-O-ethyl-rapamycin 被引量:5
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作者 陈夏琴 杨国新 +4 位作者 黄捷 余辉 金东伟 陈晓明 程元荣 《中国抗生素杂志》 CAS CSCD 北大核心 2012年第11期827-829,共3页
在雷帕霉素产生菌吸水链霉菌FC904突变株FC904-107的发酵液中发现一个雷帕霉素同系物FIM-4025,用反相硅胶柱层析等提取纯化并获得晶体。经理化性质、UV、IR、LC-MS、NMR等波谱分析,单晶X-Ray衍射确定构型,结果表明雷帕霉素同系物FIM-402... 在雷帕霉素产生菌吸水链霉菌FC904突变株FC904-107的发酵液中发现一个雷帕霉素同系物FIM-4025,用反相硅胶柱层析等提取纯化并获得晶体。经理化性质、UV、IR、LC-MS、NMR等波谱分析,单晶X-Ray衍射确定构型,结果表明雷帕霉素同系物FIM-4025与雷帕霉素化学半合成的衍生物7-O-乙基雷帕霉素同质。 展开更多
关键词 雷帕霉素产生菌突变株FC904—33 7-O-乙基雷帕霉素 单晶衍射
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High mobility group box 1 in the central nervous system:regeneration hidden beneath inflammation
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作者 Hanki Kim Bum Jun Kim +4 位作者 Seungyon Koh Hyo Jin Cho Xuelian Jin Byung Gon Kim Jun Young Choi 《Neural Regeneration Research》 SCIE CAS 2025年第1期107-115,共9页
High-mobility group box 1 was first discovered in the calf thymus as a DNA-binding nuclear protein and has been widely studied in diverse fields,including neurology and neuroscience.High-mobility group box 1 in the ex... High-mobility group box 1 was first discovered in the calf thymus as a DNA-binding nuclear protein and has been widely studied in diverse fields,including neurology and neuroscience.High-mobility group box 1 in the extracellular space functions as a pro-inflammatory damage-associated molecular pattern,which has been proven to play an important role in a wide variety of central nervous system disorders such as ischemic stroke,Alzheimer’s disease,frontotemporal dementia,Parkinson’s disease,multiple sclerosis,epilepsy,and traumatic brain injury.Several drugs that inhibit high-mobility group box 1 as a damage-associated molecular pattern,such as glycyrrhizin,ethyl pyruvate,and neutralizing anti-high-mobility group box 1 antibodies,are commonly used to target high-mobility group box 1 activity in central nervous system disorders.Although it is commonly known for its detrimental inflammatory effect,high-mobility group box 1 has also been shown to have beneficial pro-regenerative roles in central nervous system disorders.In this narrative review,we provide a brief summary of the history of high-mobility group box 1 research and its characterization as a damage-associated molecular pattern,its downstream receptors,and intracellular signaling pathways,how high-mobility group box 1 exerts the repair-favoring roles in general and in the central nervous system,and clues on how to differentiate the pro-regenerative from the pro-inflammatory role.Research targeting high-mobility group box 1 in the central nervous system may benefit from differentiating between the two functions rather than overall suppression of high-mobility group box 1. 展开更多
关键词 central nervous system damage-associated molecular pattern ethyl pyruvate glycyrhizzin high mobility group box 1 INFLAMMATION neural stem cells NEURODEVELOPMENT oligodendrocyte progenitor cells redox status REGENERATION
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氮肥和Trinexapac-ethyl对草地早熟禾草坪生长的影响
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作者 王晓英 呼天明 +3 位作者 王佺珍 田立民 张晓玲 田凯 《安徽农业科学》 CAS 北大核心 2008年第17期7222-7224,共3页
[目的]探明氮肥和Trinexapac-ethyl(TE)对草地早熟禾草坪生长的影响。[方法]采用随机区组设计对草地早熟禾草坪的剪草量及颜色进行评定。其中,氮肥设4个水平:0(N1)、20(N2)、25(N3)、30(N4)kg/(hm2·month),TE设3个水平0(TE1)、312.... [目的]探明氮肥和Trinexapac-ethyl(TE)对草地早熟禾草坪生长的影响。[方法]采用随机区组设计对草地早熟禾草坪的剪草量及颜色进行评定。其中,氮肥设4个水平:0(N1)、20(N2)、25(N3)、30(N4)kg/(hm2·month),TE设3个水平0(TE1)、312.5(TE2)、625.0(TE3)ml/(hm2·10d)。[结果]不同氮素水平和不同TE水平处理间,剪草量在各个时期差异都达极显著水平(P<0.01);N与TE的互作对草坪草剪草量影响差异不显著;在试验的各个时期,不同氮素水平下,TE2、TE3处理都比TE1处理的剪草量显著降低。不同氮素水平处理间,叶绿素含量在各个时期差异均达极显著水平(P<0.01),不同TE水平处理间以及N与TE的互作效应对草坪叶绿素含量影响在6月份后达到极显著水平(P<0.01)。在试验中,在不同时期4个氮素水平的叶绿素含量均是TE3处理含量高于TE1处理。[结论]在各个氮素水平下,使用TE均能够抑制草坪生长,改善草坪颜色。 展开更多
关键词 氮肥 Trinexapac-ethyl 草地早熟禾 生长
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我国碳酸酯类电解液溶剂的产业现状
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作者 王佳臻 《合成纤维》 CAS 2025年第1期1-3,共3页
电解液溶剂与电池的综合性能息息相关。介绍了目前国内常用的电解液溶剂及其物理性质,其中碳酸二甲酯和碳酸甲乙酯用量最大。同时主要介绍了碳酸二甲酯和碳酸甲乙酯的现阶段生产技术,对比了碳酸二甲酯生产工艺的优缺点,介绍了酯交换法... 电解液溶剂与电池的综合性能息息相关。介绍了目前国内常用的电解液溶剂及其物理性质,其中碳酸二甲酯和碳酸甲乙酯用量最大。同时主要介绍了碳酸二甲酯和碳酸甲乙酯的现阶段生产技术,对比了碳酸二甲酯生产工艺的优缺点,介绍了酯交换法合成碳酸二甲酯的主流工艺。最后分析了当前两种主要电解液溶剂的产能及市场情况,并提出未来产业发展的方向。 展开更多
关键词 电解液 碳酸二甲酯 碳酸甲乙酯
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乙醛与乙醇缩合制二乙醇缩乙醛及其裂解制乙烯基乙醚反应研究
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作者 周啟佳 陈臣举 +2 位作者 张春雷 张新平 赖克强 《化学世界》 2025年第1期53-58,共6页
乙烯基乙醚(EVE)是一种重要的高聚物单体,因此,乙醛与乙醇缩合制备二乙醇缩乙醛、二乙醇缩乙醛为原料裂解制备EVE的反应,受到越来越广泛的重视。首先以乙醛和乙醇作为第一步反应的原料,合成了二乙醇缩乙醛,再将二乙醇缩乙醛作为第二步... 乙烯基乙醚(EVE)是一种重要的高聚物单体,因此,乙醛与乙醇缩合制备二乙醇缩乙醛、二乙醇缩乙醛为原料裂解制备EVE的反应,受到越来越广泛的重视。首先以乙醛和乙醇作为第一步反应的原料,合成了二乙醇缩乙醛,再将二乙醇缩乙醛作为第二步反应的原料,裂解制得EVE。第一步反应考察了乙醛浓度、反应温度、醇/醛物质的量的比等因素对缩合反应的影响;第二步反应考察了反应温度和空速对裂解反应的影响。结果表明,第一步反应中,强酸性离子交换树脂作为催化剂制备缩乙醛具有一定的优势,AA-I树脂作为催化剂,在反应温度40℃、醇醛物质的量的比为15的条件下,乙醛的转化率和二乙醇缩乙醛的选择性分别达98.1%和100.0%;第二步反应中,所研制的AA-J催化剂具有良好的二乙醇缩乙醛的分解性能,在反应温度为300℃、空速为3.0 h-1的条件下,以质量分数为97%的二乙醇缩乙醛为原料,其转化率和EVE的选择性分别达到95.0%和97.5%。 展开更多
关键词 二乙醇缩乙醛 乙烯基乙醚 缩合 裂解
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[Sn(ethylmaltol)2I2]配合物的合成和晶体结构
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作者 路再生 《江苏师范大学学报(自然科学版)》 CAS 1996年第3期33-37,共5页
由SnI4和3-羟基-2-乙基-4(H)-吡喃酮(ethylmaltol)合成Sn(L)2I2型配合物,并进行了元素分析、UV、IR和MS表征.X射线单晶结构分析表明,该晶体属单斜晶系,空间群P21/n,a=0.76... 由SnI4和3-羟基-2-乙基-4(H)-吡喃酮(ethylmaltol)合成Sn(L)2I2型配合物,并进行了元素分析、UV、IR和MS表征.X射线单晶结构分析表明,该晶体属单斜晶系,空间群P21/n,a=0.7658(1)um,b=2.5364(4)um,c=1.1500(2)um,β=95.17°,Z=4,V=2.2246(6)um3,Dc=2.066mg/m3.收集到独立衍射点5088个,其中3913个为可观测点,最终一致化因子R=0.0448.结构分析表明Sn处于两个3-羟基-2-乙基-4(H)-吡喃酮的4个氧原子和2个碘原子的畸变的八面体配位构型中. 展开更多
关键词 3-羟基-2-乙基-4(H)-吡喃酮 锡(Ⅳ)配合物 晶体结构
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二次蒸馏法在浓香型原酒中“降乙保酸”的应用研究
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作者 赵江林 唐亮 +3 位作者 刘洋政 杨成彦 张智良 黄小东 《酿酒科技》 2025年第1期90-93,96,共5页
近年来,浓香型原酒出现了己酸乙酯和乙酸乙酯比例倒挂现象。为降低原酒中的乙酸乙酯含量,改善原酒品质,本研究利用塔式蒸馏设备对乙酸乙酯含量较高的浓香型原酒进行二次蒸馏,通过酒液中乙酸乙酯、总酸和其他挥发性成分含量的变化确定蒸... 近年来,浓香型原酒出现了己酸乙酯和乙酸乙酯比例倒挂现象。为降低原酒中的乙酸乙酯含量,改善原酒品质,本研究利用塔式蒸馏设备对乙酸乙酯含量较高的浓香型原酒进行二次蒸馏,通过酒液中乙酸乙酯、总酸和其他挥发性成分含量的变化确定蒸馏设备的塔层材质、塔层数和酒头摘取量。结果显示,当塔层数为7,酒头摘取量为4.0%时,通过紫铜材质的蒸馏设备处理原酒后,乙酸乙酯从272.79 mg/100 mL降为126.62 mg/100 mL,降低了53.58%,处理前后总酸的含量分别是1.48 g/L和1.58 g/L;经评委小组品鉴,二次蒸馏后的原酒香气较舒适、清爽、入口醇甜、酒体较协调、后味干净。二次蒸馏法能够最大程度保留原酒中总酸的含量,并降低乙酸乙酯的含量,可用于改善原酒的品质并推广使用。 展开更多
关键词 浓香型白酒 二次蒸馏 塔式蒸馏 乙酸乙酯 总酸
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Effects of Ethyl Pyruvate on Myocardial Apoptosis and Expression of Bcl-2 and Bax Proteins after Ischemia-reperfusion in Rats 被引量:26
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作者 郭家龙 张凯伦 +2 位作者 季艳梅 蒋雄刚 左顺庆 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2008年第3期281-283,共3页
In order to study the effects of ethyl pyruvate on cardiomyocyte apoptosis following ischemia/reperfusion (I/R) in vitro and the expression of Bcl-2 and Bax proteins, isolated rat hearts were perfused in a Langendor... In order to study the effects of ethyl pyruvate on cardiomyocyte apoptosis following ischemia/reperfusion (I/R) in vitro and the expression of Bcl-2 and Bax proteins, isolated rat hearts were perfused in a Langendorff model. Twenty-four rats were randomly divided into 3 groups (n=8 in each group): control group was perfused for 120 min. In the I/R group, after 30 min stabilization the injury was induced by 30 min global ischemia followed by 60 min reperfusion. Ethyl pyruvate (EP) group was set up with the same protocol as I/R group except that it was supplied with 2 mmol/L EP 15 rain before ischemia and throughout reperfusion. Myocardial malonaldehyde (MDA) content was measured. Myocardial apoptotic index (AI) was tested by terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL) method. The expression of anti-apoptotic protein Bcl-2 and pro-apoptotic protein Bax in cardiac myocytes was detected by immunohistochemistry. As compared with control group, the content of MDA, myocardial AI and the expression of Bcl-2, Bax proteins were increased significantly in I/R group, but the content of MDA, myocardial AI and the expression of Bax protein were decreased obviously and the expression of Bcl-2 protein was up-regulated in EP group (P〈0.05). These results demonstrate that EP could inhibit apoptosis of cardiac myocytes possibly via alleviating oxidative stress, up-regulating Bcl-2 and down-regulating Bax proteins. 展开更多
关键词 ethyl pyruvate myocardial reperfusion injury APOPTOSIS Bcl-2 protein Bax protein
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Synthesis and Purification of Porphyrin-Schiff Base Using Ethyl Vanillin 被引量:11
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作者 WANG Dong SU Lian-jiang +2 位作者 CHENG Xiu-li SUN Er-jun SHI Tong-shun 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2007年第2期135-137,共3页
A novel porphyrin-Schiff base was synthesized via the condensation of 5-(4-aminophenyl) -10,15,20-triphenylperphyrin and ethyl vanillin. After analyzing the level of purification of the perphyrin-Schiff base, it was... A novel porphyrin-Schiff base was synthesized via the condensation of 5-(4-aminophenyl) -10,15,20-triphenylperphyrin and ethyl vanillin. After analyzing the level of purification of the perphyrin-Schiff base, it was successfully separated. This perphyrin-Schiff base was characterized by using UV-Vis, IR,^1H NMR and MS spectroscopy. 展开更多
关键词 SYNTHESIS Porphyrin-Schiff base ethyl vanillin PURIFICATION
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