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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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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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Synthesis and Crystal Structure of 1,2-Bis(1-phenyl-3-methylthio- 4-iminopyrazolo[3,4-d]pyrimidin-5-yl) ethane
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作者 陈卫强 金桂玉 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2002年第2期136-138,共3页
The title compound 1,2-bis(1-phenyl-3-methylthio-4-iminopyrazolo[3,4-d] pyrimidin-5-yl)ethane (C26H24N10S2, Mr = 540.67) was obtained by the reaction of (1-phenyl-4- cyano)pyrazol-5-yliminomethyl ethyl ether with ethy... The title compound 1,2-bis(1-phenyl-3-methylthio-4-iminopyrazolo[3,4-d] pyrimidin-5-yl)ethane (C26H24N10S2, Mr = 540.67) was obtained by the reaction of (1-phenyl-4- cyano)pyrazol-5-yliminomethyl ethyl ether with ethyldiamine. The crystal is monoclinic, space group P21/c with a = 10.460(2), b = 8.004(2), c =15.434(3) ? b = 90.803(3)? V = 1292.1(4) 3, Z = 2, Dc = 1.390 g/cm3, F(000) = 564, m(MoKa) = 0.24 mm-1, R = 0.0560 and wR = 0.1344 for 2286 observed reflections (I > 2s (I)). In this compound the dihedral angle between the plane defined by C(2), N(1), N(2), C(3), C(6), N(3), C(4), N(4), C(5) and N(5) atoms and the phenyl ring is 34.78? The six-membered ring consisted of C(3), N(3), C(4), N(4), C(5) and C(6) atoms forms a p67 configuration in which the N(4) atom is sp2 hybrid. There exist weak hydrogen bonds between S(1) and N(5) atoms (NHS, 3.430 ?. 展开更多
关键词 crystal structure pyrazolo[3 4-d]pyrimidine purine analogs ethyl n-pyra- zolyformimidate synthesis
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新型细胞调节性死亡Parthanatos参与子痫前期胎盘损伤的机制研究
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作者 王杰 晁冰迪 +3 位作者 谢禄美 徐佳程 陈苗苗 罗欣 《实用妇产科杂志》 CAS CSCD 北大核心 2023年第6期443-448,共6页
目的:验证新型细胞调节性死亡Parthanatos在子痫前期(PE)胎盘中的发生情况,探讨抗氧化剂N-乙酰-L-半胱氨酸乙酯(NACET)对PE滋养细胞的保护作用。方法:胎盘样本选自行剖宫产手术的PE患者15例(PE组)和正常妊娠分娩的产妇15例(NP组),利用... 目的:验证新型细胞调节性死亡Parthanatos在子痫前期(PE)胎盘中的发生情况,探讨抗氧化剂N-乙酰-L-半胱氨酸乙酯(NACET)对PE滋养细胞的保护作用。方法:胎盘样本选自行剖宫产手术的PE患者15例(PE组)和正常妊娠分娩的产妇15例(NP组),利用蛋白质免疫印迹(Western blot)、实时荧光定量PCR(qRT-PCR)、免疫荧光、透射电镜评估PE患者胎盘中Parthanatos的发生情况。通过细胞计数8(CCK8)、Western blot、免疫荧光、荧光探针分别验证二甲基胍(MNNG)及NACET(分别为对照组、MNNG处理组、MNNG+NACET处理组)对HTR8/Sveno细胞Parthanatos的诱导和抑制作用。结果:①与NP组胎盘相比,PE组胎盘多聚腺苷二磷酸(ADP)核糖基聚合酶1(PARP1)mRNA及蛋白的表达增高,多聚ADP核糖(PAR)累积增多,线粒体受损严重,凋亡诱导因子(AIFM1)核定位增加,差异均有统计学意义(P<0.05)。②与对照组相比,MNNG处理组表现为可以引起HTR8/Sveno细胞PARP1蛋白的表达增高,PAR累积增多,细胞内活性氧增多,线粒体膜电位下降,AIFM1核定位增加,差异均有统计学意义(P<0.05)。③与MNNG处理组相比,MNNG+NACET处理组中5μmol/L的NACET能够显著提高细胞的存活率;伴随PARP1蛋白表达降低和PAR蛋白累积减少、细胞内活性氧水平降低、细胞核内AIFM1蛋白表达量降低、线粒体膜电位升高,差异均有统计学意义(P<0.05)。结论:PE胎盘中Parthanatos水平显著升高,MNNG可显著诱导HTR8/Sveno细胞发生PARP1依赖性的细胞调节性死亡,而NACET能够有效抑制MNNG诱导的滋养细胞Parthanatos的发生,有望成为PE临床治疗的新靶点。 展开更多
关键词 子痫前期 细胞调节性死亡Parthanatos n-乙酰-L-半胱氨酸乙酯 二甲基胍 氧化应激
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Comparison of continuous homogenous azeotropic and pressure-swing distillation for a minimum azeotropic system ethyl acetate/nhexane separation 被引量:6
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作者 Liping Lü Lin Zhu +2 位作者 Huimin Liu Hang Li Shirui Sun 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第10期2023-2033,共11页
Continuous homogenous azeotropic distillation(CHAD) and pressure-swing distillation(PSD) are explored to separate a minimum-boiling azeotropic system of ethyl acetate and n-hexane. The CHAD process with acetone as the... Continuous homogenous azeotropic distillation(CHAD) and pressure-swing distillation(PSD) are explored to separate a minimum-boiling azeotropic system of ethyl acetate and n-hexane. The CHAD process with acetone as the entrainer and the PSD process with the pressures of 0.1 MPa and 0.6 MPa in two columns are designed and simulated by Aspen Plus. The operating conditions of the two processes are optimized via a sequential modular approach to obtain the minimum total annual cost(TAC). The computational results show that the partially heat integrated pressure-swing distillation(HIPSD) has reduced in the energy cost and TAC by 40.79% and 35.94%, respectively, than the conventional PSD, and has more greatly reduced the energy cost and TAC by 62.61% and 49.26% respectively compared with the CHAD process. The comparison of CHAD process and partially HIPSD process illustrates that the partially HIPSD has more advantages in averting the product pollution, energy saving, and economy. 展开更多
关键词 蒸馏 压力 秋千 乙醇 系统 分离 年度费用 操作条件
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Growth of Kentucky Bluegrass as Influenced by Nitrogen and Trinexapacethyl 被引量:4
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作者 WANG Xiao-ying HU Tian-ming +3 位作者 WANG Quan-zhen TIAN Li-min ZHANG Xiao-ling TIAN Kai 《Agricultural Sciences in China》 CSCD 2009年第12期1498-1502,共5页
The experiment aimed to evaluate the effects of N and trinexapac-ethyl (TE) to the growth of Kentucky bluegrass. By using the method of randomized blocks design, 4 N levels, 0 (N1), 20 (N2), 25 (N3), and 30 ... The experiment aimed to evaluate the effects of N and trinexapac-ethyl (TE) to the growth of Kentucky bluegrass. By using the method of randomized blocks design, 4 N levels, 0 (N1), 20 (N2), 25 (N3), and 30 (N4) kg N ha t mon% with TE at 0 (T1), 312.5 (T2) and 625 (T3) mL ha-1 every 10 d effect on the total height, clippings and chlorophyll concentration of Kentucky bluegrass were evaluated. Results showed that total height and total clippings of Kentucky bluegrass were reduced by treating with TE and increased by treating with N. Kentucky bluegrass treated with 312.5 and 625 mL ha ' per 10 d had total clippings and total height reduced 30 and 45% under different N application level. The N × TE interaction was significant for the chlorophyll concentration of Kentucky bluegrass. The chlorophyll concentration of Kentucky bluegrass treated with TE at 625 mL ha-1 every 10 d was significantly higher than that of Kentucky bluegrass treated with 312.5 mL ha-1 every 10 d at the same N level. The chlorophyll concentration of turfgrass treated with TE at 625 mL ha-1 every 10 d receiving 30 kg N ha -1 month-1 was the highest. Based on the index of turf growth and the chlorophyll concentration, turfgrass receiving 20 or 30 kg N ha-1 month-1 with 625 mL TE ha i every 10 d could balance the problem of mowing frequency and growth quickly while keeping a good quality. 展开更多
关键词 n fertilizer trinexapac-ethyl Kentucky bluegrass
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Identification of the starting reaction position in the hydrogenation of (N-ethyl)carbazole over Raney-Ni 被引量:5
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作者 Feifei Sun Yue An +3 位作者 Lecheng Lei Fuying Wu Jingke Zhu Xingwang Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2015年第2期219-224,共6页
Hydrogenation of carbazole and N-ethylcarbazole over Raney-Ni catalyst were realized in the temperature range of 393-503 K. 4[H] adduct dominated the hydrogenation products and the formation of 2[H] adduct was the rat... Hydrogenation of carbazole and N-ethylcarbazole over Raney-Ni catalyst were realized in the temperature range of 393-503 K. 4[H] adduct dominated the hydrogenation products and the formation of 2[H] adduct was the rate-limiting step during the period, in which the conversion of carbazole was less than 40%. The hydrogenation process followed pseudo-first-order kinetics and the hydrogenation activation energies of carbazole and N-ethylcarbazole were 90 kJ/mol and 115 kJ/mol, respectively. The reaction starting position as well as the pathway of the hydrogenation of (N-ethyl)carbazole were investigated by comparing the kinetic characteristics of hydrogen uptake of carbazole and N- ethylcarbazole. The results showed that the reaction was a stepwise hydrogenation process and the first H_2 was added to the C1 = C10 double bond in the hydrogenation. 展开更多
关键词 n-ethyl)carbazole hydrogen storage Raney-ni catalyst reaction kinetics first reaction position
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Kinetic Study of Atom Transfer Radical Polymerization of 2-(N,N-Dimethylamino)ethyl Methacrylate 被引量:2
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作者 江成发 张允湘 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第2期208-213,共6页
A kinetic model was developed to describe the atom transfer radical polymerization (ATRP) of 2-(N,N-dimethylamino) ethyl methacrylate (DMAEMA). The model was based on a polymerization mechanism,which included the atom... A kinetic model was developed to describe the atom transfer radical polymerization (ATRP) of 2-(N,N-dimethylamino) ethyl methacrylate (DMAEMA). The model was based on a polymerization mechanism,which included the atom transfer equilibrium for primary radical, the propagation of growing polymer radical, and the atom transfer equilibrium for the growing polymer radical. An experiment was carried out to measure the conversion of monomer, the number-average molecular weight of polymer and molecular weight distribution for the ATRP process of DMAEMA. The experimental data were used to correlate the kinetic model and rate constants were obtained. The rate constants of activation and deactivation in the atom transfer equilibrium for primary radical are 1.0×10^4L·mol^-1·s^-1 and 0.04L·mol^-1·s^-1, respectively. The rate constant of the propagation of growing polymer radical is 8.50L·mol^-1·s^-1, and the rate constants of activation and deactivation in the atom transfer equilibrium for growing polymer radical are 0.045L·mol^-1·s^-1 and 1.2×10^5L·mol^-1·s^-1, respectively. The values of the rate constants represent the features of the ATRP process. The kinetic model was used to calculate the ATRP process of DMAEMA. The results show that the calculations agree well with the measurements. 展开更多
关键词 二甲胺 乙烷基 异丁烯酸酯 动力学 原子传递
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Reactive dividing-wall column for the co-production of ethyl acetate and n-butyl acetate 被引量:2
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作者 Hongshi Li Tong Li +2 位作者 Chunli Li Jing Fang Lihui Dong 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第1期136-143,共8页
Reactive dividing-wall column(RDWC) technology plays a critical role in the energy saving and high efficiency of chemical process.In this article, the process of co-producing ethyl acetate(EA) and n-butyl acetate(BA) ... Reactive dividing-wall column(RDWC) technology plays a critical role in the energy saving and high efficiency of chemical process.In this article, the process of co-producing ethyl acetate(EA) and n-butyl acetate(BA) with RDWC was studied.BA was not only the product, but also acted as entrainer to remove the water generated by the two esterification reactions.Experiments and simulations of the co-production process were carried out.It was found that the experimental results were in good agreement with the simulation results.Two kinds of RDWC structures(RDWC-FC and RDWC-RS) were proposed, and the co-production process operating parameters of the two types of RDWC were optimized by Aspen Plus respectively.The optimal operating parameters of the RDWC-FC were determined as follows: 0.6 of the reflux ratio of aqueous phase(RR), 0.66 of the vapor split(R_V) and 0.51 of the liquid split(R_L).And the optimal operating parameters of the RDWC-RS were shown as follows: RR was 0.295 and R_V was 0.61.Furthermore, the energy saving analysis of the co-production process was based on the annual output of 10000 tons of EA, compared with the traditional reaction distillation(RD) to prepare EA and BA, the reboiler duty of the RDWC-FC column could save 20.4%, TAC saving 23.6%; RDWC-RS reboiler energy consumption could save 17.0%, TAC 22.2%. 展开更多
关键词 REACTIVE dividing-wall columns ethyl ACETATE n-Butyl ACETATE Coproduction Energy-saving
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Synthesis and Characterization of 2-cetyl-3-20 keto acid(N-ethyl perfluorinated octyl sulfonamide) N-ethyl ester 被引量:1
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作者 翁睿 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2009年第2期292-294,共3页
2-Cetyl-3-20 keto acid(N-ethyl perfluorinated octyl sulfonamide) N-ethyl ester was synthesized by the reaction of N-ethyl-N-hydroxyethyl perfluorinated octyl sulfonamide and alky ketene dimer. The experimental resul... 2-Cetyl-3-20 keto acid(N-ethyl perfluorinated octyl sulfonamide) N-ethyl ester was synthesized by the reaction of N-ethyl-N-hydroxyethyl perfluorinated octyl sulfonamide and alky ketene dimer. The experimental results show that the yield of products can be 89% when the molar ratio of perfluorinated octyl sulfonamide to ketene dimer is 1 : 1.1 and the reaction lasts about four hours at 80 ℃. The structure of the product was characterized by FTIR and ^1HNMR. The product can dissolve in polar solvents such as NMP, DMAC, THF, DMSO, CHCl3, and 10% weight-loss temperature measured by TGA is 202℃. 展开更多
关键词 keto ester n-ethyl-n-hydroxyethyl perfluorinated octyl sulfonamide thermal performance
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N-乙基咔唑-3-甲醛席夫碱荧光探针的合成及其检测Cu^(2+)性质 被引量:1
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作者 董智云 郭昌晟 +3 位作者 高琳 顼兴宇 刘成琪 席福贵 《无机化学学报》 SCIE CAS CSCD 北大核心 2023年第5期859-866,共8页
以咔唑为原料,经过两步反应制备得到N-乙基咔唑-3-甲醛,其结构经X射线单晶衍射测定属于单斜晶系,空间群为P2_(1)/n。再以N-乙基咔唑-3-甲醛与1,3-二氨-2-丙醇为原料,设计、合成了一种新型双席夫碱荧光探针分子CMP。借助荧光光谱在体积比... 以咔唑为原料,经过两步反应制备得到N-乙基咔唑-3-甲醛,其结构经X射线单晶衍射测定属于单斜晶系,空间群为P2_(1)/n。再以N-乙基咔唑-3-甲醛与1,3-二氨-2-丙醇为原料,设计、合成了一种新型双席夫碱荧光探针分子CMP。借助荧光光谱在体积比为6∶4的DMSO/H_(2)O缓冲溶液(Tris-HCl,pH=7.0)中研究了探针CMP对Cu^(2+)的选择性识别。研究结果表明,探针CMP与Cu^(2+)以1∶2的比例配位,结合常数为1.52×10^(5) L·mol^(-1),检出限为0.205μmol·L^(-1)。回收实验表明,探针分子CMP可应用于环境水样中Cu^(2+)的检测。 展开更多
关键词 n-乙基咔唑-3-甲醛 席夫碱 荧光探针 Cu^(2+) 荧光猝灭
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Synthesis, Crystal Structure and Inhibition of N-2-Thiophenesulfonyl-α-L-phenylalanine Ethyl Ester on K562 Cell Proliferation 被引量:1
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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
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Synthesis, Crystal Structure and Antitumor Activities of N-(2-(1H-indol-3-yl)ethyl)-2-nitroaniline 被引量:1
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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
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Synthesis of Ethyl 3-Fluoroalkyl-3-Halo Acrylate With CH_2N_2
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作者 Qiao Sheng HU and Chang Ming HU(Laboratory of Organofluorine Chemistry Shanghai Institute of Organic Chemistry,Chinese Academy of Sciences,354 Fengling Lu,Shanghai,200032) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第8期673-676,共4页
When ethyl 3-fluoroalkyl-3-haloacrylate was treated with excess CH2N2,1-methyl-3-ethoxycarbonyl-4-fluoroalkylpyr azoles(3)and 1-methyl-5-ethoxycarbonyl-4-fluoroalkylpyrazoles(4)were obtained with a ratio of 90-95:10-5... When ethyl 3-fluoroalkyl-3-haloacrylate was treated with excess CH2N2,1-methyl-3-ethoxycarbonyl-4-fluoroalkylpyr azoles(3)and 1-methyl-5-ethoxycarbonyl-4-fluoroalkylpyrazoles(4)were obtained with a ratio of 90-95:10-5 in good yield. 展开更多
关键词 CH HALO MHz Synthesis of ethyl 3-Fluoroalkyl-3-Halo Acrylate With CH2n2 PPM
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ENU诱变构建Jag1基因mRNA剪接异常眼畸形小鼠模型
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作者 徐佳 魏婉娥 +3 位作者 吴秋一 释晓纯 王烁 陈兵 《河南农业科学》 北大核心 2023年第9期148-155,共8页
为建立人类和动物眼病的小鼠模型,采用乙烷基亚硝基脲(ENU)诱导C57BL/6J(B6)小鼠突变手段获得眼病小鼠,利用苏木精-伊红(HE)染色法及免疫组织化学染色技术分析小鼠角膜病变特点,通过连锁分析及位置候选克隆确定致病基因。结果显示,ENU... 为建立人类和动物眼病的小鼠模型,采用乙烷基亚硝基脲(ENU)诱导C57BL/6J(B6)小鼠突变手段获得眼病小鼠,利用苏木精-伊红(HE)染色法及免疫组织化学染色技术分析小鼠角膜病变特点,通过连锁分析及位置候选克隆确定致病基因。结果显示,ENU诱变获得1例眼畸形小鼠,小鼠角膜上皮细胞层出现明显空泡,且分化异常,角膜基质层胶原纤维排列杂乱松散,角膜内皮细胞部分脱落。染色体定位将致病基因定位于小鼠第2号染色体微卫星D2Mit107(距着丝粒65.13 cM)与D2Mit423(距着丝粒73.57 cM)之间。对候选基因齿状基因1(Jag1)测序发现,突变杂合子小鼠1条染色体上Jag1基因第24号内含子3′端AG碱基被GG碱基替代,导致第25号外显子存在7个碱基的缺失;蛋白质预测发现,该突变引起Jag1编码区移码及蛋白质编码提前终止。综合分析可知,Jag1基因突变是引起小鼠眼畸形表型的分子基础。 展开更多
关键词 小鼠 乙烷基亚硝基脲 眼畸形 基因定位 齿状基因1
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PROCESS FOR SYNTHESIS OF 3-(N-ETHYL-N- METHOXYLONEMETHYL) AMINO-4-METHYL ACCETANILIDE
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作者 Liu Yanying Li Kunlan Wang Ximeng 《精细石油化工》 CAS CSCD 北大核心 2010年第6期63-66,共4页
关键词 摘要 编辑部 编辑工作 读者
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An experimental study on N-ethyl-N-nitrosourea-induced rat brain gliomas
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作者 卞修武 史景泉 +2 位作者 陶海鹏 杨光华 辛榕 《Journal of Medical Colleges of PLA(China)》 CAS 1994年第4期241-245,共5页
AnexperimentalstudyonN-ethyl-N-nitrosourea-inducedratbraingliomasBianXiuwu(卞修武);ShiJingquan(史景泉);TaoHaipeng(... AnexperimentalstudyonN-ethyl-N-nitrosourea-inducedratbraingliomasBianXiuwu(卞修武);ShiJingquan(史景泉);TaoHaipeng(陶海鹏);YangGuanghua... 展开更多
关键词 GLIOMA n-ethyl-n-nitrosourea OnCOLOGY RATS
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An Alternative Synthesis and Crystal Structure Characterization of Nutrient Fortifier N-(1-(Phenylacetyl)-L-prolyl) Glycine Ethyl Ester
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作者 李艳如 崔建兰 +3 位作者 于思源 钟丛杉 王宁 王晓 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第10期1727-1734,1611,共9页
A nutritional fortifier N-(1-(phenylacetyl)-L-prolyl)glycine ethyl ester(4)was successfully synthesized through two synthetic schemes and characterized by IR,^1H-NMR,^13C-NMR,elemental analysis and X-ray single-crysta... A nutritional fortifier N-(1-(phenylacetyl)-L-prolyl)glycine ethyl ester(4)was successfully synthesized through two synthetic schemes and characterized by IR,^1H-NMR,^13C-NMR,elemental analysis and X-ray single-crystal diffraction.The intermediate N-phenylacetyl-L-proline(2)was synthesized by the solid-liquid reaction of L-proline and phenylacetyl chloride directly.Compound 2(C13 H15 NO3,Mr=233.26)belongs to the orthorhombic system,space group P212121 with a=8.9468(3),b=9.3190(3),c=14.0453(4)A,V=1171.03(6)A^3,Z=4,Dc=1.323 g/cm^3,μ=0.773 mm^-1,F(000)=496.0,the final R=0.0313 and wR=0.0797 for all data.Compound 4(C17 H22 N2 O4,Mr=318.36)is of orthorhombic system,space group P212121 with a=6.5831(2),b=8.5536(2),c=28.9138(9)A,V=1628.11(8)A^3,Z=4,Dc=1.299 g/cm3,μ=0.763 mm-1,F(000)=680.0,the final R=0.0353 and wR=0.0816 for all data. 展开更多
关键词 n-(1-(phenylacetyl)-L-prolyl) GLYCInE ethyl ESTER n-phenylacetyl-L-proline dicyclohexyl-carbodiimide crystal structure GLYCInE ethyl ESTER hydrochloride
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Generation of pig primary fibroblast cells harboring defective <i>MC</i>4R genes by <i>N</i>-ethyl-<i>N</i>-nitrosourea mutagenesis: A gene-driven, nontransgenic approach to pig improvement
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作者 Michiharu Sakurai Shun-ichi Suzuki +4 位作者 Tadashi Furusawa Satoshi Mikawa Tomoyuki Tokunaga Akira Onishi Takashi Awata 《American Journal of Molecular Biology》 2013年第3期139-147,共9页
Transgenic pigs have been produced with the aim of further improving pigs in terms of economic and environmental traits, but these animals have not been allowed to enter the food chain. As an alternative approach to g... Transgenic pigs have been produced with the aim of further improving pigs in terms of economic and environmental traits, but these animals have not been allowed to enter the food chain. As an alternative approach to generating pigs with novel traits of economic importance that cannot be introduced by conventional breeding, we propose a strategy for combining in vitro mutagenesis of pig primary cells with N-ethyl-N-nitrosourea (ENU) and somatic-cell nuclear transfer (SCNT) technology. To explore the feasibility of this strategy, we treated pig primary fibroblast cells with ENU, estimated the per-base mutation frequency induced by the mutagen, clonally cultured about 4000 of the mutagenized cells, and screened them for mutation within the coding region of the melanocortin-4 receptor (MC4R) gene, a key gene in energy homeostasis. Through this screening, we obtained 14 cell clones, each harboring a heterozygous base change within the coding region for MC4R. Of the mutant cell clones, each of two contained a mutant allele encoding MC4R with greatly reduced receptor activity. By SCNT using these cell clones as donors, pigs harboring mutated MC4R alleles with reduced receptor activity can be produced. Our strategy for generating pigs with novel genetic traits likely will be more acceptable to the public than is the use of transgenic technology. 展开更多
关键词 PIG Fibroblasts n-ethyl-n-nitorosourea MUTAGEnESIS
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Study of chemical kinetics on labeling of ^(99m)Tc-N-ethyl-N_2S_2-Memantine
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作者 CAO Guoxian ZHOU Xingqin +2 位作者 LIU Yingtao KONG Yanyan ZHANG Jiankang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2012年第1期52-56,共5页
In this work,a calculation method of chemical kinetics was established for labeling reaction of 99mTc-N-ethyl-N2S2-memantine,a potential NMDA receptor imaging agent prepared in our laboratory.Four groups of vials (3 v... In this work,a calculation method of chemical kinetics was established for labeling reaction of 99mTc-N-ethyl-N2S2-memantine,a potential NMDA receptor imaging agent prepared in our laboratory.Four groups of vials (3 vials per group) were added with 0.02 mL (1 mg/mL) N-ethyl-N2S2Memantine,0.08 mL (40 mg/mL) GH,0.05 mL (10 mg/mL) EDTA-2Na,0.035 mL (2 mg/mL) SnF2,0.8 mL phosphate buffer(1mol/L,pH 6.5) and 37 MBq Na99mTcO4.The vials were incubated at 70℃,80℃,90℃ or 100℃.Samples were taken with capillary from the vials at 2,5,10,20,30,40 and 60min.Labeling yields were determined by TLC.Order of reaction n,rate constant k,activation energy Ea and half life t1/2 of labeling reaction were calculated with the kinetics software we compiled.Mean labeling yields of 99m Tc-N-ethyl-N2S2-memantine at 2,5,10,20,30,40 and 60min were (1) 13.5,15.7,34.0,64.8,81.9,91.4 and 95.4 at 70℃;(2) 13.2,20.5,40.1,70.0,88.2,94.5 and 95.6 at 80℃;(3) 15.6,22.9,43.7,74.3,87.2,93.4 and 96.1 at 90℃;and (4) 20.5,25.8,45.3,81.1,92.2,95.6 and 96.0 at 100℃.The other parameters were;n =1;k=0.053,0.061,0.063 and 0.076 L/min at 70℃,80℃,90℃ and 100℃,respectively;Ea=12.38 kJ/L;t1/2=13.11,11.45,11.05 and 9.07min at 70℃,80℃,90℃ and 100℃,respectively.The mean labeling yield increased with temperature and time,optimized at 100℃ and 40-60min.The concentration of 99mTc-N-ethyl-N2S2-Memantine was larger than that of Na99mTcO4,so n=1.The k increased with reaction,hence the accelerated reaction rate at higher temperatures.The labeling reaction was not so difficult because of the low Ea.The t1/2 decreased with increasing reaction temperature,hence the acceleration of labeling reaction. 展开更多
关键词 化学动力学 乙基 标签 反应速率常数 nMDA受体 EDTA二钠 磷酸盐缓冲液
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