期刊文献+
共找到1,319篇文章
< 1 2 66 >
每页显示 20 50 100
Preparation of Ni(HCO_3)_2 and its catalytic performance in synthesis of benzoin ethyl ether 被引量:1
1
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
下载PDF
[Sn(ethylmaltol)2I2]配合物的合成和晶体结构
2
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
下载PDF
Effects of Ethyl Pyruvate on Myocardial Apoptosis and Expression of Bcl-2 and Bax Proteins after Ischemia-reperfusion in Rats 被引量:26
3
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
下载PDF
Ag_(2)O-NiTi-LDH复合材料的构建及其光催化氧化乙硫醇性能研究
4
作者 崔洪珊 何杰 +2 位作者 徐从波 赵玲玲 王丽平 《安徽建筑大学学报》 2024年第1期36-42,共7页
本文将氧化银(Ag_(2)O)负载到镍-钛层状双金属氢氧化物(NiTi-LDH)上以构建Ag_(2)O-NiTi-LDH复合材料。通过XRD、SEM、TEM、XPS、UV-vis、电化学工作站和FT-IR等技术对样品进行表征。采用静态吸附-光催化的方法对乙硫醇进行吸附氧化降解... 本文将氧化银(Ag_(2)O)负载到镍-钛层状双金属氢氧化物(NiTi-LDH)上以构建Ag_(2)O-NiTi-LDH复合材料。通过XRD、SEM、TEM、XPS、UV-vis、电化学工作站和FT-IR等技术对样品进行表征。采用静态吸附-光催化的方法对乙硫醇进行吸附氧化降解。结果表明:复合材料中Ag_(2)O和NiTi-LDH之间存在相互作用,使得Ag_(2)O-NiTi-LDH复合材料比单一基体材料的带隙能小,光生电子-空穴的分离和迁移效率高;在光催化实验中,单一的基体材料NiTi-LDH对乙硫醇的光催化效果不明显,Ag_(2)O和Ag_(2)O-NiTi-LDH虽然都能将乙硫醇光催化氧化成硫酸盐,但Ag_(2)O-NiTi-LDH复合材料光催化氧化降解效率高于Ag_(2)O。 展开更多
关键词 氧化银 镍钛-层状双金属氢氧化物 复合材料 光催化 乙硫醇
下载PDF
Synthesis of Comblike Poly(methyl methacrylate) by Atom Transfer Radical Polymerization with Poly(ethyl 2-bromoacrylate) as Macroinitiator 被引量:2
5
作者 YanSHI ZhiFengFU +1 位作者 YuDongZHANG ShuKeJIAO 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第12期1289-1292,共4页
Comblike poly(methyl methacrylate) was synthesized by atom transfer radical polymerization of methyl methacrylate with poly(ethyl 2-bromoacrylate) as a macroinitiator, which was prepared by conventional free radical p... Comblike poly(methyl methacrylate) was synthesized by atom transfer radical polymerization of methyl methacrylate with poly(ethyl 2-bromoacrylate) as a macroinitiator, which was prepared by conventional free radical polymerization of ethyl 2-bromoacrylate. The obtained comblike polymers were characterized by GPC and 1H NMR. 展开更多
关键词 Comblike polymer atom transfer radical polymerization (ATRP) MACROINITIATOR poly(methyl methacrylate) ethyl 2-bromoacrylate.
下载PDF
Synthesis, Bioactivity, and Crystal Structure Analysis of 2-(3-Oxobenzo[d]isothiazol-2(3H)-yl)ethyl Benzoates 被引量:3
6
作者 王向辉 游诚航 林强 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第8期1123-1130,共8页
Fifteen novel 2-(3-oxobenzo[d]isothiazol-2(3H)-yl)ethyl benzoates were synthesi- zed by the condensation of 2-(2-hydroxyethyl)benzo[d]isothiazol-3(2H)-one with substituted benzoic acids in dichloromethane. All... Fifteen novel 2-(3-oxobenzo[d]isothiazol-2(3H)-yl)ethyl benzoates were synthesi- zed by the condensation of 2-(2-hydroxyethyl)benzo[d]isothiazol-3(2H)-one with substituted benzoic acids in dichloromethane. All the compounds were characterized by elemental analysis, IR, ESI-MS and 1H NMR. The crystal structures for 2-(2-hydroxyethyl)benzo[d]isothiazol-3(2H)-one (2) and 2-(3-oxobenzo[d]isothiazol-2(3H)-yl)ethyl 2-methoxybenzoate (30) have been determined by X-ray crystal structure analysis. Compound 2 (C9H9NO2S) crystallizes in the monoclinic system, space group Pn with a = 10.552(3), b = 7.849(2), c = 10.765(4) A, β = 103.128(4)°, V= 868.3(5) A3, Mr = 195.24, Dc = 1.493 Mg.m-3, μ = 0.33 mm-1, F(000) = 408, Z = 4, R= 0.0314 and wR= 0.0628. Compound 30 (C17H15NO4S) crystallizes in the triclinic system, space group P1 with a = 8.028(2), b = 9.300(2), c = 10.430(3)A, V= 752.1(3)A3, Mr = 329.36, D,= 1.454 Mg.m-3, p = 0.24 mm-1, F(000) = 344, Z = 2, R = 0.0377 and wR = 0.0904. The preliminary biological test indicated that the title compounds show better growth inhibitory activity against the gram-positive bacteria than the gram-negative bacteria. 展开更多
关键词 2-(3-oxobenzo[d]isothiazoi-2(3H)-yl)ethyl benzoates synthesis crystal structure hydrogen bonds
下载PDF
Decontamination of 2-Chloroethyl Ethyl Sulfide by Pulsed Corona Plasma 被引量:1
7
作者 李战国 胡真 +1 位作者 曹鹏 赵红杰 《Plasma Science and Technology》 SCIE EI CAS CSCD 2014年第11期1054-1058,共5页
Decontamination of 2-chloroethyl ethyl sulfide (2-CEES, CH_3CH_2SCH_2CH_2C1) by pulsed corona plasma was investigated. The results show that 212.6 mg/m^3 of 2-CEES, with the gas flow rate of 2 m^3/h, can be decontam... Decontamination of 2-chloroethyl ethyl sulfide (2-CEES, CH_3CH_2SCH_2CH_2C1) by pulsed corona plasma was investigated. The results show that 212.6 mg/m^3 of 2-CEES, with the gas flow rate of 2 m^3/h, can be decontaminated to 0.09 mg/m^3. According to the variation of the inlet and outlet concentration of 2-CEES vapor with retention time, it is found that the reaction of 2-CEES in a pulsed corona plasma system follows the first order reaction, with the reaction rate constant of 0.463 s^-1. The decontamination mechanism is discussed based on an analysis of the dissociation energy of chemical bonds and decontamination products. The C-S bond adjacent to the C1 atom will be destroyed firstly to form CH3CH2S. and .CH2CH2C1 radicals. CH3CH2S. can be decomposed to .C_2H_5 and .S..S can be oxidized to SO_2, while .C_2H_5 can be finally oxidized to CO_2 and H_2O. The C-Cl bond in the .CH_2CH_2C1 radical can be destroyed to form .CH_2CH_2. and .C1, which can be mineralized to CO_2, H_2O and HCl. The H atom in the .CH_2CH_2C1 radical can also be substituted by -C1 to form CHCl_2-CHCl_2. 展开更多
关键词 pulsed corona plasma DECONTAMINATION 2-chloroethyl ethyl sulfide 2-CEES)
下载PDF
Synthesis and Crystal Structure of a Novel Ethyl 5-(4-(2-Phenylacetamido)phenyl)-1H-pyrazole-3-carboxylate as an Acrosin Inhibitor 被引量:2
8
作者 祁晶晶 周有骏 +5 位作者 刘雪飞 丁莉莉 郑灿辉 盛春泉 吕加国 朱驹 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第11期1604-1608,共5页
The title compound (ethyl5-(4-(2-phenylacetamido)phenyl)-lH-pyrazole-3-carboxylate, C20H19N3O3) was synthesized by the reaction of Claisen condensation, cyclization, reduction and acylation. The structure was ch... The title compound (ethyl5-(4-(2-phenylacetamido)phenyl)-lH-pyrazole-3-carboxylate, C20H19N3O3) was synthesized by the reaction of Claisen condensation, cyclization, reduction and acylation. The structure was characterized by X-ray diffraction, MS, NMR and IR. It belongs to the monoclinic system, space group C2/c with a = 22.723(9), b = 9.324(4), c = 18.890(8) A, β = 114.259(6)°, V = 3649(3) A^3, Dc = 1.272 Mg·m^3, Z = 8, Mr = 349.38, p = 0.087 mm^-1, F(000) = 1472, the final R = 0.0615 and wR = 0.1643. The biological test shows that the title compound has a moderate acrosin inhibition activity. 展开更多
关键词 ethyl 5-(4-(2-phenylacetamido)phenyl)-1H-pyrazole-3-carboxylate crystal structure acrosin inhibitor
下载PDF
Synthesis, Crystal Structure and Antitumor Activities of N-(2-(1H-indol-3-yl)ethyl)-2-nitroaniline 被引量:1
9
作者 贺殿 杨竹青 侯猛 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第12期1784-1788,共5页
The title compound, N-(2-(1H-indol-3-yl)ethyl)-2-nitroaniline(C16H15N3O2, Mr = 281.31), has been synthesized by the multicomponent reaction of milder Ullmann, and its structure was characterized by 1H NMR, 13 C NMR, I... The title compound, N-(2-(1H-indol-3-yl)ethyl)-2-nitroaniline(C16H15N3O2, Mr = 281.31), has been synthesized by the multicomponent reaction of milder Ullmann, and its structure was characterized by 1H NMR, 13 C NMR, IR, H RMS(ESI) and single-crystal X-ray diffraction. It crystallizes in monoclinic, space group I2/c with a = 15.0212(10), b = 9.4911(6), c = 20.3075(13) A, β = 100.776(7)o, V = 2844.1(3)A3, Z = 8, Dc = 1.314 g/cm3, F(000) = 1184.0, μ = 0.089 mm-1, the final R = 0.0574 and w R = 0.1688 for 1701 observed reflections(I 】 2σ(I)). X-ray analysis indicates three major N(2)–H(2)···O(2), C(13)–H(13)···O(2), N(2)–H(2)···N(3) hydrogen bonds and π-π stacking interactions in the crystal structure. The preliminary biological test shows that the title compound has a good antitumor activity against A549 in vitro with the IC50 value of 35 μmol/L. 展开更多
关键词 crystal structure SYNTHESIS N-(2-(1H-indol-3-yl)ethyl)-2-nitroaniline biological activity
下载PDF
Electronic and steric factors for enhanced selective synthesis of 2‐ethyl‐1‐hexanol in the Ir‐complex‐catalyzed Guerbet reaction of 1‐butanol 被引量:2
10
作者 Zhanwei Xu Peifang Yan +3 位作者 Changhui Liang Songyan Jia Xiumei Liu ZConrad Zhang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第9期1586-1592,共7页
1‐Butanol is a potential bio‐based fermentation product obtained from cellulosic biomass.As a value‐added chemical,2‐ethyl‐1‐hexanol(2‐EH)can be produced by Guerbet conversion from 1‐butanol.This work reports ... 1‐Butanol is a potential bio‐based fermentation product obtained from cellulosic biomass.As a value‐added chemical,2‐ethyl‐1‐hexanol(2‐EH)can be produced by Guerbet conversion from 1‐butanol.This work reports the enhanced catalytic Guerbet reaction of 1‐butanol to 2‐EH by a series of Cp^(*)Ir complexes(Cp^(*):1,2,3,4,5‐pentamethylcyclopenta‐1,3‐diene)coordinated to bipyridine‐type ligands bearing an ortho‐hydroxypyridine group with an electron‐donating group and a Cl−anion.The catalytic activity of the Cp^(*)Ir complex increased by increasing the electron density of the bipyridine ligand when functionalized with the para‐NMe2 and ortho‐hydroxypyridine groups.A record turnover number of 14047 was attained.A mechanistic study indicated that the steric effect of the ethyl group on theα‐C of 2‐ethylhexanal(2‐EHA)and the conjugation effect of C=C–C=O in 2‐ethylhex‐2‐enal(2‐EEA)benefits the high selectivity of 2‐EH from 1‐butanol by inhibiting the cross‐aldol reaction of 2‐EHA and 2‐EEA with butyraldehyde.Nuclear magnetic resonance study revealed the formation of a carbonyl group in the bipyridine‐type ligand via the reaction of the Cp^(*)Ir complex with KOH. 展开更多
关键词 2ethyl‐1‐hexanol Guerbet reaction 1‐Butanol IRIDIUM HYDROGENATION
下载PDF
Synthesis, Crystal Structure and Inhibition of N-2-Thiophenesulfonyl-α-L-phenylalanine Ethyl Ester on K562 Cell Proliferation 被引量:1
11
作者 薛思佳 申杰峰 +1 位作者 蔡志娟 王庆东 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第7期827-831,共5页
The title compound N-2-thiophenesulfonyl-a-L-phenylalanine ethyl ester has been synthesized. Complete assignments were achieved by IR, MS, ^1H NMR and single-crystal X-ray diffraction analyses. Using MTT assay, the in... The title compound N-2-thiophenesulfonyl-a-L-phenylalanine ethyl ester has been synthesized. Complete assignments were achieved by IR, MS, ^1H NMR and single-crystal X-ray diffraction analyses. Using MTT assay, the inhibitory rate of the title compound on K562 cells (chronic myeloid leukemic cells) was measured and the result of preliminary bioassay showed that the title compound possesses antiproliferation effects on K562 cells. In order to investigate the relationship between structure and activity of the target compound, we report its crystal structure and biological behavior in the present paper. Crystallographic data: C15H17NO4S2, Mr = 339.42, monoclinic, space group P21, flack = -0.15(12), a = 5.7916(10), b = 11.5078(19), c = 12.924(2) A, β = 97.781(3)°, Z = 2, V = 853.4(2) A^3, De = 1.321 g/cm^3, F(000) = 356, -7≤h≤7, -10≤k≤14, -15 ≤ l≤15, R = 0.0628, wR = 0.1540 and μ(MoKa) = 0.327 mm^-1. The molecule comprises a benzene and a thiofuran rings, and the intramolecular N(1)-H(1A)…O(1) makes a five-membered ring of O(1)--C(6)-C(5)--N(1)--H(1A). 展开更多
关键词 crystal structure N-2-thiophenesulfonyl-α-L-phenylalanine ethyl ester MTT assay
下载PDF
Enantioselective Hydrogenation of Ethyl 2-Oxo-4-phenylbutyrate on Cinchona-Platinum Catalysts 被引量:2
12
作者 夏涛 任其龙 吴平东 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第6期764-770,共7页
Enantioselective hydrogenation of ethyl 2-oxo-4-phenylbutyrate to ethyl (R)-2-hydroxy-4-phenyl- bu- tyrate on Pt/γ-Al2O3 modified by 10,11-dihydrocinchonidine was studied by investigating the influences of the amou... Enantioselective hydrogenation of ethyl 2-oxo-4-phenylbutyrate to ethyl (R)-2-hydroxy-4-phenyl- bu- tyrate on Pt/γ-Al2O3 modified by 10,11-dihydrocinchonidine was studied by investigating the influences of the amount of modifier, initial concentration of reactant, pressure and temperature on conversion and enantiometric excess in a stirred autoclave and the effects of the liquid velocity, gas velocity, modifier concentration and various catalytic beds in a trickle-bed reactor. The maximum optical yields were about 50% and 60% in the two types of reactors, respectively. It was assumed that the total hydrogenation rate included the reaction rates over the unmodified and modified active sites on platinum surface and a kinetic model, which fitted the experimental data well in autoclave, was obtained. A simplified plug-flow model was proposed to describe the bed average efficiency of trickle-bed reactor. 展开更多
关键词 enantioselective hydrogenation ethyl (R)-2-hydroxy-4-phenylbutyrate trickle-bed reactor KINETICS
下载PDF
Synthesis and Crystal Structure of Ethyl 3-(4-Chlorophenyl)-3,4-dihydro-6-methyl-4-oxo-2-(pyrrolidin-1-yl)furo[2,3-d]pyrimidine-5-carboxylate 被引量:2
13
作者 胡扬根 徐靖 丁明武 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第6期689-692,共4页
The crystal structure of the title compound ethyl 3-(4-chlorophenyl)-3,4-dihydro-6- methyl-4-oxo-2-(pyrrolidin-1-yl)furo[2,3-d]pyrimidine-5-carboxylate (C20H20ClN3O4, Mr= 401.84) has been prepared and determined... The crystal structure of the title compound ethyl 3-(4-chlorophenyl)-3,4-dihydro-6- methyl-4-oxo-2-(pyrrolidin-1-yl)furo[2,3-d]pyrimidine-5-carboxylate (C20H20ClN3O4, Mr= 401.84) has been prepared and determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/n with a = 20.6215(9), b = 8.5311(4), c = 21.6886(9) A^°, β = 91.607(1)°, V = 3814.0(3)A^°^3, Z = 8, Dc = 1.400 g/cm^3, F(000) = 1680, μ = 0.233 mm^-1, R = 0.0718 and wR = 0.1545 for 6717 observed reflections with I 〉 2σ(I). X-ray diffraction analysis reveals two crystallographically independent molecules in the asymmetric unit. 展开更多
关键词 crystal structure ethyl 3-(4-ehlorophenyl)-3 4-dihydro-6-methyl-4-oxo-2- (pyrrolidin-1-yl)furo[2 3-d]pyrimidine-5-earboxylate aza-Wittig reaction synthesis
下载PDF
2-Ethyl-9,10-anthraquinone assisted sol–gel synthesis of Pd/γ-Al2O3 nanorods with enhanced catalytic performance in 2-ethyl-9,10-anthraquinone hydrogenation 被引量:4
14
作者 Weiquan Cai Junlin Zhuo +1 位作者 Jimin Fang Zhichao Yang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第8期1863-1869,共7页
A series of nanorod-like porous Pd/γ-Al2 O3 catalysts with controllable textural properties and enhanced catalytic performance in 2-ethyl-9,10-anthraquinone(eAQ) hydrogenation for H2 O2 preparation were successfully ... A series of nanorod-like porous Pd/γ-Al2 O3 catalysts with controllable textural properties and enhanced catalytic performance in 2-ethyl-9,10-anthraquinone(eAQ) hydrogenation for H2 O2 preparation were successfully prepared via a facile sol-gel method using aluminum isopropoxide as aluminum precursor and eAQ as structure directing agent,sequential calcination and impregnation process with Na2 PdCl4 solution.The physicochemical properties of the catalysts obtained with different addition amounts of eAQ.were comparatively characterized by XRD,TG-DSC,BET,TEM,CO-TPR,H2-TPR and H2-O2 titration.The results show that addition of eAQ can not only effectively control the textural properties(surface area,pore volume and average pore size) of the catalysts,but also lower their reduction temperature of active metal.Importantly,the catalyst obtained with an addition amount of 4 wt% eAQ shows the highest hydrogenation efficiency of 10.28 g·L^-1,which is 37.3% higher than 7.49 g·L^-1 of the catalyst obtained without eAQ. 展开更多
关键词 Catalyst HYDROGENATION Alumina 2-ethyl-9 10-anthraquinone Structure directing agent H2O2
下载PDF
枯草芽孢杆菌PW2挥发性产物对黄曲霉的抑制作用 被引量:1
15
作者 张凯歌 魏琛 +4 位作者 余璐 杜明艳 李晓冉 林亲录 王青云 《食品与生物技术学报》 CAS CSCD 北大核心 2024年第5期122-129,共8页
为探寻安全、高效的黄曲霉新型抑制物,采用顶空固相微萃取-气质联用(HS-SPME-GC-MS)技术对枯草芽孢杆菌(Bacillus subtilis)PW2所产具有抗霉活性的挥发性有机化合物(volatile organic compounds,VOCs)进行了成分鉴定,并利用平板对扣法... 为探寻安全、高效的黄曲霉新型抑制物,采用顶空固相微萃取-气质联用(HS-SPME-GC-MS)技术对枯草芽孢杆菌(Bacillus subtilis)PW2所产具有抗霉活性的挥发性有机化合物(volatile organic compounds,VOCs)进行了成分鉴定,并利用平板对扣法从鉴定出的成分中筛选具有强抗霉活性的目标化合物,通过平板对扣法和96孔板梯度稀释法测定目标化合物对黄曲霉的最小抑菌体积分数(MIC),使用黄曲霉毒素B_(1)(aflatoxin B_(1),AFB_(1))ELISA检测试剂盒分析了目标化合物对黄曲霉产AFB_(1)的抑制作用,使用扫描电子显微镜(scanning electron microscope,SEM)观察受试黄曲霉孢子形态的变化和采用分光光度法测定受试黄曲霉细胞膜麦角甾醇相对含量,以探讨抗霉机理。结果显示,从PW2所产VOCs中共鉴定出41种组分,并从中筛选出异辛醇为目标化合物;平板对扣法和96孔板梯度稀释法测得异辛醇对黄曲霉的MIC分别为0.169μL/mL和6.25μL/mL;PDB培养基中异辛醇体积分数分别为3.13、6.25、12.50μL/mL时,均能有效抑制AFB_(1)的产生,且随异辛醇体积分数的升高,抑制效果增强;异辛醇处理可导致黄曲霉孢子表面凹陷和孢子破裂,并且影响细胞膜中麦角甾醇的相对含量,造成细胞膜受损。该研究可为开发以异辛醇为功能成分的黄曲霉抑制剂提供理论参考。 展开更多
关键词 枯草芽孢杆菌 挥发性有机化合物 异辛醇 黄曲霉
下载PDF
Catalytic conversion of ethyl lactate to 1,2-propanediol over CuO 被引量:1
16
作者 Song Zhang Zhibao Huo +4 位作者 Dezhang Ren Jiang Luo Jun Fu Lu Li Fangming Jin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第1期126-131,共6页
An efficient conversion of biomass-derived ethyl lactate to 1,2-propanediol(1,2-PDO) over CuO was investigated.Among the catalysts we tested, CuO, Cu2 O and Co showed excellent catalytic activity for the conversion of... An efficient conversion of biomass-derived ethyl lactate to 1,2-propanediol(1,2-PDO) over CuO was investigated.Among the catalysts we tested, CuO, Cu2 O and Co showed excellent catalytic activity for the conversion of ethyl lactate to 1,2-PDO in water, and CuO was more active and gave the best result. The 1,2-PDO yield of 93.6% was achieved when Zn acted as a reductant. The results indicated that in situ formed hydrogen by the oxidation of Zn in water is more effective than gaseous hydrogen, which failed to produce the 1,2-PDO from ethyl lactate.From a practical point of view, the present method may provide a useful route for the production of 1,2-PDO from ethyl lactate. 展开更多
关键词 Biomass 1 2-propanediol ethyl lactate CuO Hydrothermal reactions
下载PDF
Long-term and combined effects of N-[2-(nitrooxy)ethyl]-3-pyridinecarboxamide and fumaric acid on methane production,rumen fermentation, and lactation performance in dairy goats 被引量:1
17
作者 Zongjun Li Xinjian Lei +3 位作者 Xiaoxu Chen Qingyan Yin Jing Shen Junhu Yao 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2022年第3期852-863,共12页
Background:In recent years,nitrooxy compounds have been identified as promising inhibitors of methanogenesis in ruminants.However,when animals receive a nitrooxy compound,a high portion of the spared hydrogen is eruct... Background:In recent years,nitrooxy compounds have been identified as promising inhibitors of methanogenesis in ruminants.However,when animals receive a nitrooxy compound,a high portion of the spared hydrogen is eructated as gas,which partly offsets the energy savings of CH4mitigation.The objective of the present study was to evaluate the long-term and combined effects of supplementation with N-[2-(nitrooxy)ethyl]-3-pyridinecarboxamide(NPD),a methanogenesis inhibitor,and fumaric acid(FUM),a hydrogen sink,on enteric CH4production,rumen fermentation,bacterial populations,apparent nutrient digestibility,and lactation performance of dairy goats.Results:Twenty-four primiparous dairy goats were used in a randomized complete block design with a 2×2factorial arrangement of treatments:supplementation without or with FUM(32 g/d)or NPD(0.5 g/d).All samples were collected every 3 weeks during a 12-week feeding experiment.Both FUM and NPD supplementation persistently inhibited CH4yield(L/kg DMI,by 18.8%and 18.1%,respectively)without negative influence on DMI or apparent nutrient digestibility.When supplemented in combination,no additive CH4suppression was observed.FUM showed greater responses in increasing the molar proportion of propionate when supplemented with NPD than supplemented alone(by 10.2%vs.4.4%).The rumen microbiota structure in the animals receiving FUM was different from that of the other animals,particularly changed the structure of phylum Firmicutes.Daily milk production and serum total antioxidant capacity were improved by NPD,but the contents of milk fat and protein were decreased,probably due to the bioactivity of absorbed NPD on body metabolism.Conclusions:Supplementing NPD and FUM in combination is a promising way to persistently inhibit CH4emissions with a higher rumen propionate proportion.However,the side effects of this nitrooxy compound on animals and its residues in animal products need further evaluation before it can be used as an animal feed additive. 展开更多
关键词 Bacterial populations Dairy goat Fumaric acid Lactation performance Methane emissions N-[2-(nitrooxy)ethyl]-3-pyridinecarboxamide Rumen fermentation
下载PDF
Solvent-free Mechanochemical and Liquid-phase Reaction of [60]Fullerene with Ethyl 2-Diazopropionate
18
作者 YuJinLI RuFangPENG +1 位作者 YouChengLIU GuanWuWANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第11期1265-1268,共4页
The solvent-free mechanochemical reaction and the liquid-phase reaction of C60 with ethyl 2-diazopropionate prepared in situ or preformed from alanine ethyl ester hydrochloride and sodium nitrite have been investigate... The solvent-free mechanochemical reaction and the liquid-phase reaction of C60 with ethyl 2-diazopropionate prepared in situ or preformed from alanine ethyl ester hydrochloride and sodium nitrite have been investigated. Methanofullerene 1 and fulleroids 2 and 3 from these reactions were obtained, meanwhile the pyrazoline intermediate was not observed. Fulleroids 2 and 3 can be converted to methanofullerene 1 in refluxing toluene. 展开更多
关键词 FULLERENE ethyl 2-diazopropionate METHANOFULLERENE fulleroid.
下载PDF
Al_(2)(SO_(4))_(3)催化热解油转化生产酯类燃料
19
作者 罗丹 夏淑倩 +4 位作者 郭丽潇 韩建荣 蒋可为 郝全爱 李娇 《河北科技大学学报》 CAS 北大核心 2024年第3期283-289,共7页
酸类、糖类等不稳定组分的存在是制约热解油直接用作生物燃料的主要因素。为了解决此问题,提出采用Al_(2)(SO_(4))_(3)催化剂将这些不稳定成分酯化为燃料类化合物的途径。首先,分别以单模型化合物左旋葡萄糖或乙酸为原料,考察各种金属... 酸类、糖类等不稳定组分的存在是制约热解油直接用作生物燃料的主要因素。为了解决此问题,提出采用Al_(2)(SO_(4))_(3)催化剂将这些不稳定成分酯化为燃料类化合物的途径。首先,分别以单模型化合物左旋葡萄糖或乙酸为原料,考察各种金属硫酸盐催化其转化制备乙酰丙酸乙酯或乙酸乙酯的能力,筛选出催化性能最好的催化剂;其次,以左旋葡萄糖和乙酸的模型混合物为原料,探究Al_(2)(SO_(4))_(3)催化同时转化制备酯类的最佳反应条件;最后,以真实热解油为原料,验证Al_(2)(SO_(4))_(3)在最佳反应条件下催化酯化的可行性。结果表明,酯化后热解油中大部分酸、糖、醛消失,同时产生大量的酯和缩醛,酯类和缩醛类占改性热解油总色谱面积的39.5%。Al_(2)(SO_(4))_(3)能有效将热解油中的酸类、糖类等不稳定组分酯化为燃料类化合物,可为热解油转化制备生物燃料提供借鉴。 展开更多
关键词 催化化学 热解油 乙酰丙酸乙酯 乙酸乙酯 Al_(2)(SO_(4))_(3)
下载PDF
Synthesis and Crystal Structure of Tri(4-(3-hydroxy2-ethyl-4-pyridinone-1-yl)-aniline Condensation Salicylaldehydato) Monohydratotricopper(II)Dimethylformamide Monohydrate Solvate 被引量:2
20
作者 LUZai-Sheng NIUDe-Zhong +1 位作者 TUShu-Jiang CHENJiu-Tong 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2003年第6期681-686,共6页
The title complex [Cu3L3(H2O)]DMFH2O (H2L = 4-(3-hydroxy-2-ethyl-4- pyridinone-1-yl)-aniline condensation salicylaldehyde) was obtained. The single-crystal X-ray study shows that it is a trinuclear compound [Cu3(C20H1... The title complex [Cu3L3(H2O)]DMFH2O (H2L = 4-(3-hydroxy-2-ethyl-4- pyridinone-1-yl)-aniline condensation salicylaldehyde) was obtained. The single-crystal X-ray study shows that it is a trinuclear compound [Cu3(C20H15N2O3)3(H2O)]DMFH2O. The coordi- nation sphere about each copper ion in the complex consists of two oxygen atoms from hydroxylpyridinone moiety of one ligand and one oxygen and one nitrogen atoms from salicyladehyde Schiff-base moiety of another ligand arranged in a slightly distorted square planar geometry. Among the three copper ions, one (Cu(2)) is coordinated by the other oxygen atom of water molecule on the fifth coordinate position to form a distorted square pyramid geometry. The crystal is of monoclinic, space group P21/c with a = 12.9202(5), b = 27.197(1), c = 17.0116(7) ? b = 100.588(1), V = 5875.9(4) 3, Z = 4, C63H57N7O12Cu3, Mr = 1294.78, Dc = 1.464 g/cm3, m = 1.146 mm-1, F(000) = 2668, R = 0.0784 and wR = 0.1546 for 6926 observed reflections with I > 2s(I). The differences of coordinate bond lengths are observed between anhydrous and hydrous units: in the former unit, the average bond lengths are 1.978 ?for CuN (azomethine), 1.883 ?for CuO (phenolic) in Schiff-base moiety, 1.959 ?for CuO (keto), and 1.919 ?for CuO (hydroxy) in hydroxypyridinone moiety; while those in the latter are longer with the following corresponding values: 1.985(5), 1.908(5), 1.993(5) and 1.919(4) ? respectively. The Cu(2)O (water) bond length is 2.375(6) ? 展开更多
关键词 copper(II) complex 4-(3-hydroxy-2-ethyl-4-pyridinone-1-yl)-aniline salicylaldehyde Schiff-base crystal structure
下载PDF
上一页 1 2 66 下一页 到第
使用帮助 返回顶部